@article{DuezelvanPraagSendtner2016,
  author    = {D{\"u}zel, Emrah and van Praag, Henriette and Sendtner, Michael},
  title     = {Can physical exercise in old age improve memory and hippocampal function?},
  series = {Brain},
  volume    = {139},
  journal   = {Brain},
  number    = {3},
  doi       = {10.1093/brain/awv407},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-190721},
  pages     = {662-673},
  year      = {2016},
  abstract  = {Physical exercise can convey a protective effect against cognitive decline in ageing and Alzheimer's disease. While the long-term health-promoting and protective effects of exercise are encouraging, it's potential to induce neuronal and vascular plasticity in the ageing brain is still poorly understood. It remains unclear whether exercise slows the trajectory of normal ageing by modifying vascular and metabolic risk factors and/or consistently boosts brain function by inducing structural and neurochemical changes in the hippocampus and related medial temporal lobe circuitry—brain areas that are important for learning and memory. Hence, it remains to be established to what extent exercise interventions in old age can improve brain plasticity above and beyond preservation of function. Existing data suggest that exercise trials aiming for improvement and preservation may require different outcome measures and that the balance between the two may depend on exercise intensity and duration, the presence of preclinical Alzheimer's disease pathology, vascular and metabolic risk factors and genetic variability.},
  language  = {en}
}
@article{FrerichsSirenFeuersteinetal.1992,
  author    = {Frerichs, K. and Sir{\`e}n, Anna-Leena and Feuerstein, G. and Hallenbeck, JM},
  title     = {The onset of postischemic hypoperfusion in rats is precipitous and may be controlled by local neurons},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-47980},
  year      = {1992},
  abstract  = {Background and Purpose: Reperfusion following transient global cerebral ischemia is characterized by an initial hyperemic phase, which precedes hypo perfusion. The pathogenesis of these flow derangements remains obscure. Our study investigates the dynamics of postischemic cerebral blood flow changes, with particular attention to the role of local neurons. Metho(Js: We assessed local cortical blood flow continuously by laser Doppler flowmetry to permit observation of any rapid flow changes after forebrain ischemia induced by four-vessel occlusion for 20 minutes in rats. To investigate the role of local cortical neurons in the regulation of any blood flow fluctuations, five rats received intracortical microinjections of a neurotoxin (10 p,g ibotenic acid in 1 p,1; 1.5-mm-depth parietal cortex) 24 hours before ischemia to induce selective and localized neuronal depletion in an area corresponding to the sampie volume of the laser Doppler probe (1 mm3 ). Local cerebral blood flow was measured within the injection site and at an adjacent control site. Results: Ischemia was followed by marked hyperemia (235 ±23\% of control, n =7), followed by secondary hypoperfusion (45±3\% of control, n=7). The transition from hyperemia to hypoperfusioo occurred not gradually but precipitously (maximal slope of flow decay: 66±6\%/min; n=7). In ibotenic acid-injected rats, hyperemia was preserved at the injection site, but the sudden decline of blood flow was abolished (maximal slope of flow decay: 5±3\%/min compared with 53±8\%/min at the control site; n=5, p<O.OOI) and 00 significant hypoperfusion de\eloped (103±20\% of control at 60 minutes). Conclusions: These data suggest that the rapid transition to cortical hypo perfusion after forebrain ischemia may be triggered locally by a neuronal mechanism but that this mechanism does not underlie the initial hyperemia.},
  subject      = {Gehirn},
  language  = {en}
}