Filtern
Volltext vorhanden
- ja (125)
Gehört zur Bibliographie
- ja (125)
Erscheinungsjahr
Dokumenttyp
Schlagworte
- active zone (13)
- cGMP (8)
- Guanylatcyclase (7)
- Kaliumkanal (7)
- Maus (7)
- optogenetics (7)
- ANP (6)
- Atriales natriuretisches Hormon (6)
- synapse (6)
- Drosophila (5)
- Niere (5)
- Aldosteron (4)
- Cyclo-GMP (4)
- GC-A (4)
- Knockout <Molekulargenetik> (4)
- SPRED2 (4)
- Signaltransduktion (4)
- Taufliege (4)
- cAMP (4)
- Blutdruck (3)
- Bruchpilot (3)
- Drosophila melanogaster (3)
- Elektrophysiologie (3)
- Fibrose (3)
- Gen-Knockout (3)
- Genregulation (3)
- Ionenkanal (3)
- Migration (3)
- NGF (3)
- Nozizeption (3)
- PDZ-Domain (3)
- Renin-Angiotensin-System (3)
- Rezeptor (3)
- Spred-Proteine (3)
- Synapse (3)
- aldosterone (3)
- dSTORM (3)
- kidney (3)
- mineralocorticoid receptor (3)
- neuromuscular junction (3)
- nociception (3)
- plasticity (3)
- potassium (3)
- super-resolution microscopy (3)
- Aktive Zone (2)
- Angiogenese (2)
- Angiotensin II (2)
- CA3 (2)
- Calciumkanal (2)
- Capsaicin (2)
- Cyclo-AMP (2)
- Electrophysiology (2)
- Genexpression (2)
- Glatte Muskulatur (2)
- Guanylylcyclase (2)
- HDBSCAN (2)
- Herzmuskelzelle (2)
- Immunfluoreszenz (2)
- K2P (2)
- Kidney (2)
- Kollagen (2)
- Latrophilin (2)
- MAP-Kinase (2)
- Mena (2)
- Mineralokortikoidrezeptor (2)
- NO-sensitive Guanylyl-Cyclase (2)
- NO-sensitive guanylyl cyclase (2)
- OCD (2)
- Ochratoxin A (2)
- PDZ-Domäne (2)
- PFE (2)
- Potassium Channel (2)
- Proteine (2)
- Proteinkinase C (2)
- Proximaler Tubulus (2)
- RIM1α (2)
- Renin-Angiotensin-Aldosteron-System (2)
- Stickstoffmonoxid (2)
- Synaptische Transmission (2)
- TRESK (2)
- VASP (2)
- acute brain slices (2)
- behavior (2)
- dCIRL (2)
- depression (2)
- electron tomography (2)
- heart (2)
- high-pressure freezing/freeze substitution (2)
- hippocampus (2)
- inflammation (2)
- insulin (2)
- mechanotransduction (2)
- migration (2)
- neurotransmitter release (2)
- nitric oxide (2)
- physiology (2)
- presynaptic (2)
- smooth muscle (2)
- synaptic plasticity (2)
- 2-photon microscopy (1)
- 2-pore potassium channel (1)
- 212-2 (1)
- ADHD (1)
- ADP-Rezeptor (1)
- AGEs (1)
- AP1 (1)
- Adeno (1)
- Adhesion-GPCR (1)
- Advanced Glycation Endproducts (1)
- Afferenzen (1)
- Aktive Zonen (1)
- Albumin (1)
- Aldosteronantagonist (1)
- Aldosterone (1)
- Alzheimer' Disease (1)
- Alzheimer' schen Erkrankung (1)
- Alzheimer-Krankheit (1)
- Amygdala (1)
- Amyloid <beta-> (1)
- Anandamid (1)
- Ang II (1)
- Angiopoietin-1 (1)
- Antidepressivum (1)
- Aorta (1)
- Apoptose (1)
- Apoptosis (1)
- Arachidonsäure (1)
- Arteriogenese (1)
- Atherosklerose (1)
- Atrial natriuretic peptide (1)
- Atriales Natriuretisches Peptid (1)
- Atriales natriuretisches Peptid (1)
- Aureobasidium (1)
- Axotomie (1)
- B-Typ Natriuretisches Peptid (1)
- BNP (1)
- BRET (1)
- Bauchspeicheldrüse (1)
- Behavioral neuroscience (1)
- Beta-Receptor (1)
- Beta-Rezeptor (1)
- Bindestelle (1)
- Bindungsstellen (1)
- Bleomycin (1)
- Botulinustoxin (1)
- Brain natriuretic Peptide (1)
- C-type natriuretic peptide (1)
- CA2+ channels (1)
- CA3 pyrimidal cells (1)
- CGRP (1)
- CNG channel (1)
- CNP (1)
- CNS (1)
- COX2 expression (1)
- CRE (1)
- CRISPR/Cas-Methode (1)
- CX3CR1 (1)
- Ca2+ channels (1)
- Ca2+i handling (1)
- CaV1.2 und PMCA4b (1)
- Ca\(^{2+}\) channels (1)
- Cadherin-13 (CDH13) (1)
- Calcium (1)
- Calcium-ATPasen (1)
- Calciumkanäle (1)
- Calciumoscillations (1)
- Calciumoszillationen (1)
- Calpain (1)
- Cav1.2 and PMCA4b (1)
- Cavβ subunit (1)
- Cell (1)
- Channelrhodopsin (1)
- Channelrhodopsin-2 (1)
- Chemokine (1)
- Chordontonal organ (1)
- Clostridium perfringens (1)
- Corpus amygdaloideum (1)
- Corticosteroide (1)
- Cranial window (1)
- Cremaster (1)
- Crespi effect (1)
- Cyclic GMP (1)
- D2 receptors (1)
- DMPS (1)
- DNS-Chip (1)
- DRG (1)
- DeepSqueak (1)
- Differentielle Genexpression (1)
- Drosophila melanogaster motoneuron (1)
- ECM (1)
- EGF (1)
- EGFR (1)
- ERK (1)
- Endocannabinoide (1)
- Endocytosis (1)
- Endothelium (1)
- Endozytose (1)
- Epidermaler Wachstumsfaktor (1)
- Epithelzelle (1)
- Epsilon-Toxin (1)
- Estrogen receptor (1)
- Exzitatorische Synapse (1)
- FRET (1)
- Fibronektin (1)
- Fluorescence (1)
- Fluoreszenzmikroskopie (1)
- Fluoxetin (1)
- Fluoxetine (1)
- FoxO3 (1)
- Fractalkin (1)
- Furchungsteilung (1)
- G protein coupled receptors (1)
- G-Protein-gekoppelte Rezeptoren (1)
- GABA\(_{A}\) receptors (1)
- GC-A Rezeptor (1)
- GDNF (1)
- GIRK (1)
- GMPcGMP-dependent protein kinase I (1)
- GPCR (1)
- GST (1)
- Gastrointestinaltrakt (1)
- Gelatinasen (1)
- Genfallen-Insertion (1)
- Gentransfer (1)
- Glykolisierung (1)
- Glykosaminoglykane (1)
- Guanylatzklase-A (1)
- Guanylatzyklase (1)
- Guanylyl Cyclase A (1)
- Guanylyl cyclase A (1)
- Guanylyl cyclase-A (1)
- Guanylyl-Cyclase (1)
- Guanylylzyklase (1)
- Guanylylzyklase-Rezeptoren (1)
- HIS (1)
- HPA Axis (1)
- Halothan (1)
- Halothane (1)
- Hebbian plasticity (1)
- Hebbsche Lernregel (1)
- Herzfunktion (1)
- Herzhypertrophie (1)
- Herzmuskel (1)
- Heteromerisierung (1)
- Hippocampus (1)
- Hippokampus (1)
- Hirnzelle (1)
- Hitze (1)
- Hitzeantwort (1)
- Hochauflösende Lichtmikroskopie (1)
- Hyaluronsäure (1)
- Hypertonie (1)
- Hypophysen-Zwischenhirn-System (1)
- Hypothalamisch-hypophysäre Achse (1)
- IBA-1 (1)
- Idiopathische pulmonale Fibrose (1)
- Immunfluorescence (1)
- In vivo imaging (1)
- Indischer Hanf (1)
- Inhalationsanästhetika (1)
- Innervation (1)
- Insulin (1)
- Insulinsekretion (1)
- Integrine (1)
- IntelliCage (1)
- Interaktion (1)
- Interaktionen (1)
- Japankärpfling (1)
- Johnstons organ (1)
- K-Kanäle (1)
- Kalium (1)
- Kaliumkanäle mit zwei Poren-Domänen (1)
- Kaliumstrom (1)
- Kanal (1)
- Kanalkinetik (1)
- Kinetik (1)
- Kir-Kanäle (1)
- Knie (1)
- Knock out (1)
- Knock-Out <Molekulargenetik> (1)
- Knock-out Maus (1)
- Knockout mouse (1)
- Kollagenhomöostase (1)
- Konditioniertes Lernen (1)
- Küken (1)
- Küken-Spinalganglienneurone (1)
- L-type calcium channels (1)
- LIF (1)
- LTCC-independent function of Cavβ (1)
- Left Ventricular Hypertrophy (1)
- Linksherzhypertrophie (1)
- Lunge (1)
- Lungenfibrose (1)
- MAP Kinase Signaling (1)
- MAPK signaling (1)
- MDCK (1)
- MDCK-F cells (1)
- MDCK-F-Zellen (1)
- Massenspektrometrie (1)
- Mechanorezeptor (1)
- Mechanosensation (1)
- Mechanotransduktion (1)
- Mena promoter ativity (1)
- Mena-Promotor-Aktivität (1)
- MiMIC (1)
- Microarray (1)
- Midblastula-transition MBT MZT (1)
- Mikroglia (1)
- Mikrozirkulation (1)
- Mineralocorticoidrezeptor (1)
- Motilität (1)
- Mouse (1)
- Mouse model (1)
- Munc13-3 (1)
- Muscarinrezeptor (1)
- Myofibroblast (1)
- NF-kappa-B (1)
- NF-kappaB (1)
- NF-κB (1)
- NO-GC (1)
- NPR-A (1)
- NPR-C (1)
- NRF2 (1)
- Natriuretisches Hormon (1)
- Nephrotoxine (1)
- Nervenzelle (1)
- Neurobiologie (1)
- Neuronale Plastizität (1)
- Neurons (1)
- Neuropathie (1)
- Neurotrophe Faktoren (1)
- Neurotrophic Factors (1)
- Neurowissenschaften (1)
- Neutrophile (1)
- Nicotinischer Acetylcholinrezeptor (1)
- Nierenfunktion (1)
- OAT1 (1)
- OTA (1)
- Opossum Kidney Zellen (1)
- Opossum kidney cells (1)
- Optogenetik (1)
- PDE (1)
- PDE3 (1)
- PET (1)
- PFA in ethanol (1)
- PI-3-Kinase (1)
- PKG I (1)
- PNS (1)
- PTH1R (1)
- Perizyt (1)
- Phosphodiesterase 3 (1)
- Phosphorylierung (1)
- Physiologie (1)
- Plastizität (1)
- Plastizität <Physiologie> (1)
- Polarisation (1)
- Potassium channel (1)
- Potassium channels (1)
- Primary failure of eruption (1)
- Primäre Zahndurchbruchstörung (1)
- Proliferation (1)
- Protein Kinase C (1)
- Protein-Interaktionspartner (1)
- Protein-Protein Interaction (1)
- Protein-Protein-Interaktion (1)
- Protein-Protein-Interaktionen (1)
- Protein-protein-interaction (1)
- Proteininteraktion (1)
- Proteinkinase A (1)
- Proteinurie (1)
- Proton (1)
- Pulmonary fibrosis (1)
- Pulmonary hypertension (1)
- Pulswellengeschwindigkeit (1)
- Quecksilber (1)
- RGS2 (1)
- RIM (1)
- RIM-binding protein (1)
- RNS-Spleißen (1)
- ROMK2 (1)
- RSK (1)
- Ras-Raf-Signalweg (1)
- Renin Angiotensin System (1)
- Rezeptor-vermittelte Protein Endozytose (1)
- S6KII RSK (1)
- SH3 (1)
- SLC2A3 (1)
- SNARE proteins (1)
- SPRED (1)
- SPRED2-defiziente Mäuse (1)
- STORM (1)
- SV pool (1)
- Schmerz (1)
- Schrecken (1)
- Schreckstarre (1)
- Sensitivität (1)
- Serotonin (1)
- Serotonin-1A (1)
- Serotonin-7 (1)
- Signaltransduction (1)
- Signalwege (1)
- Sildenafil (1)
- Sorting (1)
- Spannungskontrollierter Ionenkanal (1)
- Spectrin (1)
- Spinalganglienneurone (1)
- Spred Protein (1)
- Sternzelle (1)
- Steroidhormon (1)
- Stickstoffoxide (1)
- Strommessung (1)
- Synaptische Vesikel (1)
- Synaptotagmin (1)
- TASK (1)
- TASK-1 (1)
- TASK-3 (1)
- TBI (1)
- TEVC (1)
- TGF-β (1)
- TMT (1)
- TRPC3 (1)
- TRPC6 (1)
- TSPO (1)
- Thrombozytenaggregationshemmung (1)
- Transaktivierung (1)
- Transforming Growth Factor beta 1 (1)
- Transkription <Genetik> (1)
- Transkriptionsfaktor (1)
- Transporter (1)
- Transverse Aortenkonstriktion (1)
- Tyrosine Kinase (1)
- Unc-13 (1)
- Vasodilatator-stimuliertes Phosphoprotein (1)
- Venlafaxin (1)
- Venlafaxine (1)
- Volumenregulation (1)
- WIN 55 (1)
- Wasserstoffperoxid (1)
- X-Gal staining (1)
- X-Gal-Färbung (1)
- Xenopus Oozyten (1)
- Xenopus oocytes (1)
- Yeast-Two-Hybrid-Screening (1)
- Zahndurchbruch (1)
- Zellkultur (1)
- Zellmigration (1)
- Zelltod (1)
- Zellvolumen (1)
- Zentralnervensystem (1)
- Zone 1-HSC (1)
- Zwangsstörung (1)
- Zwei-Elektroden-Spannungsklemme (1)
- Zygote (1)
- \(\alpha\)-latrotoxin (1)
- aGPCR (1)
- acetylcholine M1 receptor (1)
- action potential (1)
- acute MK-801 (1)
- adenoviruses (1)
- adhesion GPCR (1)
- adhesion-GPCR (1)
- advanced glycation endproducts (1)
- albumine (1)
- albuminuria (1)
- alveolar bone (1)
- amyloid (1)
- analysis of variance (1)
- anandamide (1)
- animal model (1)
- antidepressant (1)
- anxiety (1)
- apoptosis (1)
- atrial natriuretic peptide (1)
- autoradiography (1)
- axonal transport (1)
- axotomy (1)
- bPAC (1)
- beige adipocytes (1)
- binding (1)
- binding sites (1)
- biophysics (1)
- black yeast (1)
- bleomycin (1)
- bloodpressure (1)
- cGKI (1)
- cGMP/cAMP-Crosstalk (1)
- cTRPV1 (1)
- caenorhabditis elegans (1)
- calcineurin signaling cascade (1)
- calcium (1)
- calcium channel (1)
- calcium signaling (1)
- calcium signalling (1)
- calcium-imaging (1)
- cardiac hypertrophy (1)
- cardiac pacing (1)
- cardiomyocytes (1)
- cardiovascular remodeling (1)
- cells (1)
- cementoclasts (1)
- cementum (1)
- cerebellar cortex (1)
- channel (1)
- channelrhodopsin (1)
- chemokines (1)
- chick (1)
- chick DRG (1)
- choanoflagellates (1)
- chordotonal organs (1)
- chronic heart failure (1)
- closed head injury (1)
- collagen homeostasis (1)
- compaction (1)
- contact-kinin system (1)
- correlative light and electron microscopy (1)
- coupling (1)
- cremaster (1)
- cyclic (1)
- cyclic nucleotides (1)
- cylic GMP (1)
- damage control orthopedics (1)
- decompensated heart failure (1)
- delayed rectifier potassium channel (1)
- development (1)
- diffuse (1)
- direct stochasticoptical reconstruction microscopy (1)
- dissociation (1)
- domain (1)
- domain K\(^{+}\) channels (1)
- dorsal root ganglions (1)
- drosophila larvae (1)
- drug discovery (1)
- dunce (1)
- epsilon-toxin (1)
- erectile dysfunction (1)
- excitation-secretion coupling (1)
- facilitation (1)
- fat development (1)
- femoral fracture (1)
- fibronectin (1)
- fibrosis (1)
- flexibility (1)
- fluorescence imaging (1)
- fluorescent probes (1)
- fluorescent-probes (1)
- focal (1)
- freezing (1)
- fungal rhodopsins (1)
- gap junction (1)
- gastrointestinal tract (1)
- gelatinases (1)
- gene-trap (1)
- glucosaminoglycane (1)
- glutamate receptor (1)
- guanylyl cyclase (1)
- guanylyl cyclase-A (1)
- guanylyl cylcase A (1)
- hERG (1)
- hIK1 (1)
- hOAT (1)
- hOAT1 (1)
- hearing (1)
- heat (1)
- heat response (1)
- heteromerisation (1)
- high contrast (1)
- high-pressure freezing (1)
- hippocampal (1)
- hippocampal mossy fiber bouton (1)
- hippocampal-neurons (1)
- homeostasis (1)
- human induced pluripotent stem cell (hiPSC) (1)
- human neurons (1)
- hyaluronic acid (1)
- hyperalgesia (1)
- hyperexpression techniques (1)
- hypertension (1)
- image data (1)
- immunohistochemistry (1)
- induced neural stem cells (1)
- induced pluripotent stem cells (1)
- inertial idiothetic navigation (1)
- inhalational anesthetics (1)
- initiation (1)
- innervation (1)
- innexins (1)
- integrin (1)
- interacting PDZ domain (1)
- interaction (1)
- interstitial fibrosis (1)
- interstitielle Fibrose (1)
- interval timing (1)
- intracellular receptors (1)
- inward rectifier (1)
- junction proteins (1)
- kardiovaskuläres Remodeling (1)
- kinetics (1)
- knee (1)
- knockout (1)
- kollagen (1)
- ligand CD55 (1)
- light-sensitive anion channel (1)
- localization micoscopy (1)
- localization microscopy (1)
- long QT syndrome (1)
- lower urinary tract (1)
- macrophages (1)
- mass spectrometry (1)
- mechanisms (1)
- mediale Amygdala (1)
- median and dorsal raphe (1)
- melanoma malignancy (1)
- membrane trafficking (1)
- memory (1)
- mercury (1)
- metabotropic signalling (1)
- mfg-e8 (1)
- mice (1)
- microbial rhodopsins (1)
- microcirculation (1)
- migraine (1)
- mitochondrial biogenesis (1)
- mitochondrial transport (1)
- modulation (1)
- molecular biology (1)
- molecular mechanisms (1)
- molecular neuroscience (1)
- monocytes (1)
- morris water maze (1)
- mortality (1)
- mossy fiber synapse (1)
- mossy fiber synapses (1)
- motility (1)
- motoneuron (1)
- mouse (1)
- mrsk2 KO mouse (1)
- mutation (1)
- myocardial infarction (1)
- myofibroblast (1)
- myofibroblasts (1)
- nAChR (1)
- nanoarchitecture (1)
- nanodomain (1)
- nanotopology (1)
- natiuretische Peptide (1)
- natriuretic peptide (1)
- natriuretic peptides (1)
- navigation (1)
- nephrotoxins (1)
- nervous-system (1)
- neural circuits (1)
- neural networks (1)
- neurobiology (1)
- neuroinflammation (1)
- neurons (1)
- neuropathic pain (1)
- neuropathy (1)
- neuropsychiatric disorders (1)
- neuroscience (1)
- neurotoxins (1)
- neurotransmission (1)
- neutrophil granulocytes (1)
- neutrophile Granulocyten (1)
- neutrophils (1)
- nicht-genotrope Steroidwirkungen (1)
- nongenotropic steroid effects (1)
- obesity (1)
- object recognition memory (1)
- ochratoxin a (1)
- octopamine (1)
- organotypic slice cultur (1)
- organotypische Schnittkultur (1)
- osteoclasts (1)
- pain (1)
- pankreatische ß-Zellen (1)
- pericyte (1)
- pericytes (1)
- periodontitis (1)
- phosphodiesterases (PDEs) (1)
- phosphorylation (1)
- phosphorylation sites (1)
- photoreceptor (1)
- physiologiesche Angiogene (1)
- plan sciences (1)
- platelets (1)
- platform (1)
- pollen tube (1)
- potassium-channel (1)
- potentiation (1)
- presynaptic calcium (1)
- presynaptic differentiation (1)
- presynaptic homeostasis (1)
- presynaptic plasticity (1)
- primary afferent (1)
- protein coupled receptors (1)
- protein kinase (1)
- protein kinase C (1)
- protein-coupled receptors (1)
- proteininteraction (1)
- proteins (1)
- proton channel (1)
- psychiatric disorders (1)
- pulmonary hypertension (1)
- rapid gene induction (1)
- rat hippocampal neurons (1)
- rats (1)
- receptor channel (1)
- receptor-mediated-endocytosis (1)
- reconstruction (1)
- release (1)
- resolution limit (1)
- reveals (1)
- rhodopsin (1)
- rhodopsin phosphodiesterase (RhoPDE) (1)
- riociguat (1)
- senile plaque (1)
- seniler Plaques (1)
- sensory neurons (1)
- sensory physiology (1)
- serotonin (1)
- serotonin transporter deficient mice (1)
- serotonin-1A (1)
- serotonin-7 (1)
- serotonin-specific neurons (1)
- serum responsive element (1)
- seven-helix receptor (1)
- shear stress (1)
- signal transduction pathway (1)
- signalling pathways (1)
- small interfering RNAs (1)
- soluble guanylyl cyclase (1)
- spatial navigation (1)
- spontaneous network activity (1)
- stress (1)
- structure-function relationships (1)
- structured illumination microscopy (1)
- substratal idiothetic navigation (1)
- surface potential recording (1)
- synapse formation (1)
- synaptic delay (1)
- synaptic inhibition (1)
- synaptic transmission (1)
- synaptic ultrastructure (1)
- synaptic vesicles (1)
- synaptische Plastizität (1)
- synaptotagmin (1)
- teeth (1)
- thrombosis (1)
- tooth eruption (1)
- transactivation (1)
- transfection (1)
- transgenic mouse (1)
- transient bursting (1)
- transmission (1)
- transmission electron microscopy (1)
- transmitter release (1)
- transporter (1)
- traumatic brain injury (1)
- two-electrode-voltage clamp (1)
- two-pore domain potassium channels (1)
- ultrasound vocalizations (1)
- unterer Harntrakt (1)
- voltage-gated Na\(^+\) channel (1)
- weight drop (1)
- white (1)
- white blood cells (1)
- wistar rats (1)
- xenopus oocytes (1)
- Östrogene (1)
- Östrogenrezeptor (1)
- Überexpression (1)
- β-cells (1)
Institut
- Physiologisches Institut (125) (entfernen)
Sonstige beteiligte Institutionen
Anxiety disorders and depression are common comorbidities in cardiac patients. Mice lacking the serotonin transporter (5-HTT) exhibit increased anxiety-like behavior. However, the role of 5-HTT deficiency on cardiac aging, and on healing and remodeling processes after myocardial infarction (MI), remains unclear. Cardiological evaluation of experimentally naïve male mice revealed a mild cardiac dysfunction in ≥4-month-old 5-HTT knockout (−/−) animals. Following induction of chronic cardiac dysfunction (CCD) by MI vs. sham operation 5-HTT−/− mice with infarct sizes >30% experienced 100% mortality, while 50% of 5-HTT+/− and 37% of 5-HTT+/+ animals with large MI survived the 8-week observation period. Surviving (sham and MI < 30%) 5-HTT−/− mutants displayed reduced exploratory activity and increased anxiety-like behavior in different approach-avoidance tasks. However, CCD failed to provoke a depressive-like behavioral response in either 5-Htt genotype. Mechanistic analyses were performed on mice 3 days post-MI. Electrocardiography, histology and FACS of inflammatory cells revealed no abnormalities. However, gene expression of inflammation-related cytokines (TGF-β, TNF-α, IL-6) and MMP-2, a protein involved in the breakdown of extracellular matrix, was significantly increased in 5-HTT−/− mice after MI. This study shows that 5-HTT deficiency leads to age-dependent cardiac dysfunction and disrupted early healing after MI probably due to alterations of inflammatory processes in mice.
A shear-dependent NO-cGMP-cGKI cascade in platelets acts as an auto-regulatory brake of thrombosis
(2018)
Mechanisms that limit thrombosis are poorly defined. One of the few known endogenous platelet inhibitors is nitric oxide (NO). NO activates NO sensitive guanylyl cyclase (NO-GC) in platelets, resulting in an increase of cyclic guanosine monophosphate (cGMP). Here we show, using cGMP sensor mice to study spatiotemporal dynamics of platelet cGMP, that NO-induced cGMP production in pre-activated platelets is strongly shear-dependent. We delineate a new mode of platelet-inhibitory mechanotransduction via shear-activated NO-GC followed by cGMP synthesis, activation of cGMP-dependent protein kinase I (cGKI), and suppression of Ca2+ signaling. Correlative profiling of cGMP dynamics and thrombus formation in vivo indicates that high cGMP concentrations in shear-exposed platelets at the thrombus periphery limit thrombosis, primarily through facilitation of thrombus dissolution. We propose that an increase in shear stress during thrombus growth activates the NO-cGMP-cGKI pathway, which acts as an auto-regulatory brake to prevent vessel occlusion, while preserving wound closure under low shear.
In dorsal root ganglia (DRG) neurons TRESK channels constitute a major current component of the standing outward current IK\(_{SO}\). A prominent physiological role of TRESK has been attributed to pain sensation. During inflammation mediators of pain e.g. lysophosphatidic acid (LPA) are released and modulate nociception. We demonstrate co-expression of TRESK and LPA receptors in DRG neurons. Heterologous expression of TRESK and LPA receptors in Xenopus oocytes revealed augmentation of basal K\(^{+}\) currents upon LPA application. In DRG neurons nociception can result from TRPV\(_{1}\) activation by capsaicin or LPA. Upon co-expression in Xenopus oocytes LPA simultaneously increased both depolarising TRPV\(_{1}\) and hyperpolarising TRESK currents. Patch-clamp recordings in cultured DRG neurons from TRESK[wt] mice displayed increased IK\(_{SO}\) after application of LPA whereas under these conditions IK\(_{SO}\) in neurons from TRESK[ko] mice remained unaltered. Under current-clamp conditions LPA application differentially modulated excitability in these genotypes upon depolarising pulses. Spike frequency was attenuated in TRESK[wt] neurons and, in contrast, augmented in TRESK[ko] neurons. Accordingly, excitation of nociceptive neurons by LPA is balanced by co-activation of TRESK channels. Hence excitation of sensory neurons is strongly controlled by the activity of TRESK channels, which therefore are good candidates for the treatment of pain disorders.
Neurotransmitter release is stabilized by homeostatic plasticity. Presynaptic homeostatic potentiation (PHP) operates on timescales ranging from minute- to life-long adaptations and likely involves reorganization of presynaptic active zones (AZs). At Drosophila melanogaster neuromuscular junctions, earlier work ascribed AZ enlargement by incorporating more Bruchpilot (Brp) scaffold protein a role in PHP. We use localization microscopy (direct stochastic optical reconstruction microscopy [dSTORM]) and hierarchical density-based spatial clustering of applications with noise (HDBSCAN) to study AZ plasticity during PHP at the synaptic mesoscale. We find compaction of individual AZs in acute philanthotoxin-induced and chronic genetically induced PHP but unchanged copy numbers of AZ proteins. Compaction even occurs at the level of Brp subclusters, which move toward AZ centers, and in Rab3 interacting molecule (RIM)-binding protein (RBP) subclusters. Furthermore, correlative confocal and dSTORM imaging reveals how AZ compaction in PHP translates into apparent increases in AZ area and Brp protein content, as implied earlier.
The second messengers, cyclic adenosine 3′-5′-monophosphate (cAMP) and cyclic guanosine 3′-5′-monophosphate (cGMP), play important roles in many animal cells by regulating intracellular signaling pathways and modulating cell physiology. Environmental cues like temperature, light, and chemical compounds can stimulate cell surface receptors and trigger the generation of second messengers and the following regulations. The spread of cAMP and cGMP is further shaped by cyclic nucleotide phosphodiesterases (PDEs) for orchestration of intracellular microdomain signaling. However, localized intracellular cAMP and cGMP signaling requires further investigation. Optogenetic manipulation of cAMP and cGMP offers new opportunities for spatio-temporally precise study of their signaling mechanism. Light-gated nucleotide cyclases are well developed and applied for cAMP/cGMP manipulation. Recently discovered rhodopsin phosphodiesterase genes from protists established a new and direct biological connection between light and PDEs. Light-regulated PDEs are under development, and of demand to complete the toolkit for cAMP/cGMP manipulation. In this review, we summarize the state of the art, pros and cons of artificial and natural light-regulated PDEs, and discuss potential new strategies of developing light-gated PDEs for optogenetic manipulation.
Typisch für die Alzheimer' schen Erkrankung ist die Bildung unlöslicher Ablagerungen im Gehirn, sogenannter "seniler Plaques". Diese Plaques bestehen im Wesentlichen aus fibrillärem beta-Amyloid, das durch Glykierungen verändert vorliegen kann. Außerdem beinhalten die Plaques, sogenannte AGEs "Advanced Glycation Endproducts", die aus nichtenzymatisch glykierten Proteinen entstehen. Diese AGE-modifizierten Proteine sowie das fibrilläre beta-Amyloid sind in der Lage Mikrogliazellen zu aktivieren. Die sessilen Gehirnmakrophagen wirken in aktiviertem Zustand neurotoxisch, wobei es verschiedene Hypothesen gibt, wie die Mikrogliazellen zu dem neuronalen Zelltod führen. Um dieses zu untersuchen wurden murine Mikrogliazellen herangezogen, die als Merkmal ihrer Aktivierung auf die Translokation des Transkriptionsfaktors NF-kappa-B in den Zellkern überprüft wurden. In der vorliegenden Arbeit wurden die Rahmenbedingungen näher untersucht, die zu der AGE vermittelten Mikrogliaaktivierung führen. Es wurde in vitro gezeigt, daß die Mikrogliaaktivierung zunächst durch eine hochmolekulare Hyaluronsäure, wie sie nativ in der extrazellulären Matrix vorliegt, verhindert wird. Im Gegensatz dazu konnte NF-kappa-B in Mikrogliazellen aktiviert werden, die in Gegenwart von Hyaluronsäurefragmenten mit AGE behandelt wurden. In der vorliegenden Arbeit wurde festgestellt, daß die Mikrogliaaktivierbarkeit umgekehrt proportional zu der durchschnittlichen Hyaluronsäuremolekülgröße ist. Andere Glykosaminoglykane aus der extrazellulären Matrix, wie D-Glukuronsäure, N-Azetylglukosamin oder Chondroitin-4-sulfat reduzierten die Aktivierbarkeit der Mikrogliazellen nur geringfügig. Sowohl beta-Amyloid, als auch AGEs setzen während ihres Entstehungsprozesses reaktive Sauerstoffspezies frei, die Hyaluronsäure in kleinere Bruchstücke zerschneiden können. Die Signaltransduktion der AGE-aktivierten Mikrogliazellen wurde mittels unterschiedlicher Inhibitoren gehemmt und die Auswirkung auf die NF-kappa-B Aktivierung untersucht. Hier zeigte sich ein komplexes Netzwerk an aktivierten Signalwegen, so daß kein Rückschluß auf einen bestimmten Rezeptor möglich war. Daher wurde ein "in vitro Modell" entwickelt, um die ausschlaggebende neurotoxischen Komponenten der Mikrogliareaktion aufzufinden. Darin wurden die Signalkaskaden der aktivierten Mikroglia erneut durch pharmakologische Inhibierung unterbrochen, das zellfreie Medium das von diesen Mikrogliazellen sezerniert wurde, wurde als "konditioniertes Medium" für die Kultur muriner Neuronen eingesetzt. Diese wurden bezüglich ihrer Überlebensrate in diesem konditionierten Medium untersucht. Die Hemmung der Transkription oder der Translation in den Mikrogliazellen zeigte keine Reduktion der neurotoxischen Wirkung des konditionierten Mediums. Ebensowenig wirkten Inhibitoren der mitochondrialen Atmungskette, der Radikalquellen Xanthin Oxidase, Lipoxygenase oder Cyclooxygenase. Die Hemmung der NADPH Oxidase reduzierte die Neurotoxizität des konditionierten Mediums auf etwa 30 Prozent. Die NADPH Oxidase ist ein Enzymkomplex, der im Rahmen des "oxidativen bursts" große Mengen Superoxidanionen freisetzt. Um die Bedeutung der NADPH Oxidase Aktivierung für die neurotoxische Wirkung nachzuweisen, wurde eine Untereinheit der NADPH Oxidase, das membranständige gp91phox in den Mikrogliazellen deaktiviert. Dies führte dazu, daß diese Zellen kein Superoxid auf die Stimulation mit beta-Amyloid oder AGE hin abgaben, im Gegensatz zu den Mikrogliazellen mit funktioneller NADPH Oxidase. Das konditionierte Medium der NADPH Oxidase defizienten Zellen war nicht mehr neurotoxisch. Die freien Sauerstoffradikale die aufgrund der NADPH Oxidase Aktivierung entstehen, können zu einer NF-kappa-B Aktivierung führen. NF-kappa-B wurde erfolgreich in den Mikroglia durch exogenes Wasserstoffperoxid stimuliert, wobei aber keine neurotoxische Wirkung im Modellsystem festgestellt wurde. NF-kappa-B scheint damit nicht für die mikrogliavermittelte Neurotoxizität verantwortlich zu sein, im Gegensatz zu der NADPH Oxidase, deren Aktivität unmittelbar mit der Neurotoxizität korreliert ist.
Hintergrund: Die interstitielle Fibrose spielt bei der Verschlechterung der Nierenfunktion mit dem Endstadium der Urämie eine große Rolle. In diesem Geschehen kommt der Interaktion der im Krankheitsfall vermehrt filtrierten Proteine mit der proximalen Tubuluszelle, dem Ort der Proteinrückresorption, eine entscheidende Bedeutung zu. Das Ziel der vorliegenden Arbeit war es, anhand eines Zellkulturmodells den Einfluss eines vermehrten Albuminangebots auf die Kollagenhomöostase kultivierter proximaler Tubuluszellen zu untersuchen, dabei involvierte Signaltransduktionswege aufzuzeigen und die zentrale Rolle der Albuminendozytose im Rahmen des Geschehens zu beurteilen. Methoden: Für unsere Untersuchungen verwendeten wir überwiegend die kultivierten proximalen Tubuluszellen des Opossums, welche – wie auch die LLC-PK1 Zellen - die für die Proteinendozytose notwendigen Komponenten - nämlich die Rezeptoren Megalin und Cubilin sowie den Natrium-Protonen-Austauscher 3 – besitzen und somit eine hohe Endozytoserate aufweisen. Diese wurden mit Albuminkonzentrationen - wie man sie bei erhöhter Proteinfiltration unter pathophysiologischen Bedingungen findet - inkubiert. Für Vergleichsstudien zogen wir Zelllinien mit niedriger endozytotischer Aktivität (MDCK-, IHKE-1-, NHE3-defiziente-OK-Zellen) heran. Die Kollagenhomöostase wurde mittels Kollagenase-sensitiven Prolininkorporationsassay, Kollagen-ELISA und Kollagen-Western Blot, die Aktivität der Matrixmetalloproteinasen mittels Zymographie und Gelatinaseassay erfasst. Die Aktivierung von Signaltransduktionswegen wurde mittels eines SEAP-Reporter Gen Assays untersucht. Ergebnisse: Albuminexposition führte bei den Zelllinien mit hoher endozytotischer Aktivität (OK- und LLC-PK1- Zellen) zu einer vermehrten Sekretion von Kollagen Typ I, III und IV. Bei den Zelllinien mit niedriger endozytotischer Aktivität (MDCK-, IHKE-1-, NHE3-defiziente-OK-Zellen) kam es nach Albuminexposition zu einem Rückgang der Kollagensekretion. Im Kollagen-Western Blot zeigte sich nach Inkubation mit Albumin eine Zunahme des zellulären Kollagens. Mittels Zymographie und Gelatinaseassay konnte eine Albumin-induzierte Abnahme der MMP-Aktivität nachgewiesen werden. Inkubation der OK-Zellen mit Albumin führte im SEAP-Reporter-Gen-Assay zu einer Aktivierung des NF-kappaB-, AP-1- und CRE-Singalweges. Hemmung der NF-kappaB-, PKC- und PKA- Aktivierung hatte eine teilweise Reduktion der Albumin-inudzierten Kollagensekretion zur Folge. Eine Hemmung der Rezeptor-vermittelten Endozytose mittels des NHE3-Inhibitors EIPA verminderte sowohl die Kollagensekretion als auch die Aktivierung der untersuchten Signaltransduktionswege. Diskussion: Unsere Daten zeigen, dass ein Mehrangebot an Albumin die Kollagenhomöostase der proximalen Tubuluszellen aufgrund einer vermehrten Kollagensynthese und eines verminderten Kollagenabbaus stört. Dabei scheinen vor allem Kollagen Typ I und III zur tubulointerstitiellen Fibrose beizutragen. Albuminexposition aktiviert PKC, PKA, NF-kappaB, AP1 und CRE. Für PKC, PKA und NF-kappaB konnte eine direkte Beteiligung an der Albumin-induzierten Kollagensekretion nachgewiesen werden. Albumin muss mittels Rezeptor-vermittelter Endozytose in die proximale Tubuluszelle aufgenommen werden, um die beobachteten Effekte zu vermitteln. Die alleinige Anwesenheit von Protein im proximalen Tubulus reicht dafür nicht aus. Es ist anzunehmen, dass die gestörte Matrixhomöostase zu einer Progression der interstitiellen Fibrose und somit zum Fortschreiten der Niereninsuffizienz führt. Albuminurie ist also nicht nur ein Marker, sondern ein Motor der Nierenfibrose.
Based on recent findings that show that depletion of factor XII (FXII) leads to better posttraumatic neurological recovery, we studied the effect of FXII-deficiency on post-traumatic cognitive and behavioral outcomes in female and male mice. In agreement with our previous findings, neurological deficits on day 7 after weight-drop traumatic brain injury (TBI) were significantly reduced in FXII\(^{−/−}\) mice compared to wild type (WT) mice. Also, glycoprotein Ib (GPIb)-positive platelet aggregates were more frequent in brain microvasculature of WT than FXII\(^{−/−}\) mice 3 months after TBI. Six weeks after TBI, memory for novel object was significantly reduced in both female and male WT but not in FXII\(^{−/−}\) mice compared to sham-operated mice. In the setting of automated home-cage monitoring of socially housed mice in IntelliCages, female WT mice but not FXII\(^{−/−}\) mice showed decreased exploration and reacted negatively to reward extinction one month after TBI. Since neuroendocrine stress after TBI might contribute to trauma-induced cognitive dysfunction and negative emotional contrast reactions, we measured peripheral corticosterone levels and the ration of heart, lung, and spleen weight to bodyweight. Three months after TBI, plasma corticosterone levels were significantly suppressed in both female and male WT but not in FXII\(^{−/−}\) mice, while the relative heart weight increased in males but not in females of both phenotypes when compared to sham-operated mice. Our results indicate that FXII deficiency is associated with efficient post-traumatic behavioral and neuroendocrine recovery.
Introduction
Structural plasticity with synapse formation and elimination is a key component of memory capacity and may be critical for functional recovery after brain injury. Here we describe in detail two surgical techniques to create a cranial window in mice and show crucial points in the procedure for long-term repeated in vivo imaging of synaptic structural plasticity in the mouse neocortex.
Methods
Transgenic Thy1-YFP(H) mice expressing yellow-fluorescent protein (YFP) in layer-5 pyramidal neurons were prepared under anesthesia for in vivo imaging of dendritic spines in the parietal cortex either with an open-skull glass or thinned skull window. After a recovery period of 14 days, imaging sessions of 45–60 min in duration were started under fluothane anesthesia. To reduce respiration-induced movement artifacts, the skull was glued to a stainless steel plate fixed to metal base. The animals were set under a two-photon microscope with multifocal scanhead splitter (TriMScope, LaVision BioTec) and the Ti-sapphire laser was tuned to the optimal excitation wavelength for YFP (890 nm). Images were acquired by using a 20×, 0.95 NA, water-immersion objective (Olympus) in imaging depth of 100–200 μm from the pial surface. Two-dimensional projections of three-dimensional image stacks containing dendritic segments of interest were saved for further analysis. At the end of the last imaging session, the mice were decapitated and the brains removed for histological analysis.
Results
Repeated in vivo imaging of dendritic spines of the layer-5 pyramidal neurons was successful using both open-skull glass and thinned skull windows. Both window techniques were associated with low phototoxicity after repeated sessions of imaging.
Conclusions
Repeated imaging of dendritic spines in vivo allows monitoring of long-term structural dynamics of synapses. When carefully controlled for influence of repeated anesthesia and phototoxicity, the method will be suitable to study changes in synaptic structural plasticity after brain injury.
The study of animal development is one of the oldest disciplines in the field of biology and the collected data from countless investigations on numerous species have formed a general understanding of the animal life-cycle. Almost one century ago, one consequence of these intense investigations was the discovery of specific morphological changes that occur during the cleavage phase, a period that follows fertilization and egg activation at the very beginning of animal embryogenesis. These observations resulted into the formulation of the concept of a midblastula transition (MBT). So far, the mechanism of the nucleo-cytoplasmic ratio model is the only one that explains MBT regulation in a satisfying way. It suggests that the MBT is controlled by several maternal repressive factors in the egg, which are titrated out by every cell division until they lose their repressing potential. Although this regulatory mechanism was proven for several species and in different approaches, it is still only a rudimentary model for MBT control and leaves numerous questions unanswered. On this conceptual background, this thesis has shown that embryos from the medaka fish (Oryzias latipes) lose their cell cycle synchrony already after the fourth or fifth round of cell divisions, and replace it by a metasynchronous divisions pattern, in which cell division occurs in clear waves beginning in the embryo's center. The reason for this change in division mode is still unknown, although several hypotheses were put forward, most notable a difference in yolk-access between cells. However, this theory was weakened by division waves that progressed from one embryonic pole to the opposing one, which were occasionally observed in deformed embryos, leaving the mechanism for this phenomenon furthermore unclear. Those deformed embryos were most likely the result of asymmetric cell divisions at very early stages, a phenomenon which occurred in a significant percentage of medaka embryos and which directly influenced the equal distribution of cytoplasmic material. It could not beuncovered what kind of effects this unequal distribution of cytoplasm exerted on the progression of embryonic development, but it can be argued that relevant differences in cell volumes could result in cell clusters that will enter MBT at different time points. Comparable observations were already made in other species and it was hypothesized that they were the direct results of early unequal cell cleavages. Finally, it was demonstrated that zygotic transcription in medaka embryos is activated prior to the hitherto assumed time of the first transcriptional initiation. Moreover, indications were found that strongly speak for a transcriptional activation that occurs in two steps; a first step at the 16-cell stage when first cells were identified positive for RNAPII phosphorylation, and a second step at the 64-cell stage, when the number of p-RNAPII positive cells significantly increased. A stepwise activation of zygotic transcription was already observed in other species, but only for the overall increasing amount of mRNAs and irrespective of the actual number of transcriptionally active cells within the embryos. .. Overall, these data confirm and expand the basic knowledge of pre-MBT embryos and about the MBT itself. Furthermore, they also suggest that many early processes in pre-MBT embryos are only rudimentarily understood or still totally unknown.