TY - JOUR A1 - Albert-Weissenberger, Christiane A1 - Stetter, Christian A1 - Meuth, Sven G. A1 - Göbel, Kerstin A1 - Bader, Michael A1 - Sirén, Anna-Leena A1 - Kleinschnitz, Christoph T1 - Blocking of Bradykinin Receptor B1 Protects from Focal Closed Head Injury in Mice by Reducing Axonal Damage and Astroglia Activation JF - Journal of Cerebral Blood Flow and Metabolism N2 - The two bradykinin receptors B1R and B2R are central components of the kallikrein–kinin system with different expression kinetics and binding characteristics. Activation of these receptors by kinins triggers inflammatory responses in the target organ and in most situations enhances tissue damage. We could recently show that blocking of B1R, but not B2R, protects from cortical cryolesion by reducing inflammation and edema formation. In the present study, we investigated the role of B1R and B2R in a closed head model of focal traumatic brain injury (TBI; weight drop). Increased expression of B1R in the injured hemispheres of wild-type mice was restricted to the later stages after brain trauma, i.e. day 7 (P<0.05), whereas no significant induction could be observed for the B2R (P>0.05). Mice lacking the B1R, but not the B2R, showed less functional deficits on day 3 (P<0.001) and day 7 (P<0.001) compared with controls. Pharmacological blocking of B1R in wild-type mice had similar effects. Reduced axonal injury and astroglia activation could be identified as underlying mechanisms, while inhibition of B1R had only little influence on the local inflammatory response in this model. Inhibition of B1R may become a novel strategy to counteract trauma-induced neurodegeneration. KW - R-715 KW - kinin receptors KW - closed head injury KW - β-APP KW - astrocytes KW - TNF-α Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-125903 VL - 32 IS - 9 ER - TY - JOUR A1 - Kunze, Ekkehard A1 - Pham, Mirko A1 - Raslan, Furat A1 - Stetter, Christian A1 - Lee, Jin-Yul A1 - Solymosi, Laszlo A1 - Ernestus, Ralf-Ingo A1 - Hamilton Vince, Giles A1 - Westermaier, Thomas T1 - Value of Perfusion CT, Transcranial Doppler Sonography and Neurological Examination to detect delayed Vasospasm after aneurysmal Subarachnoid Hemorrhage [Research Article] N2 - Background If detected in time, delayed cerebral vasospasm after aneurysmal subarachnoid hemorrhage (SAH) may be treated by balloon angioplasty or chemical vasospasmolysis in order to enhance cerebral blood flow (CBF) and protect the brain from ischemic damage. This study was conceived to compare the diagnostic accuracy of detailed neurological examination, Transcranial Doppler Sonography (TCD), and Perfusion-CT (PCT) to detect angiographic vasospasm. Methods The sensitivity, specificity, positive and negative predictive values of delayed ischemic neurological deterioration (DIND), pathological findings on PCT- maps, and accelerations of the mean flow velocity (MVF) were calculated. Results The accuracy of DIND to predict angiographic vasospasm was 0.88. An acceleration of MFV in TCD (>140 cm/s) had an accuracy of 0.64, positive PCT-findings of 0.69 with a higher sensitivity, and negative predictive value than TCD. Interpretation Neurological assessment at close intervals is the most sensitive and specific parameter for cerebral vasospasm. PCT has a higher accuracy, sensitivity and negative predictive value than TCD. If detailed neurological evaluation is possible, it should be the leading parameter in the management and treatment decisions. If patients are not amenable to detailed neurological examination, PCT at regular intervals is a helpful tool to diagnose secondary vasospasm after aneurysmal SAH. KW - Medizin Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-76241 ER - TY - JOUR A1 - Westermaier, Thomas A1 - Stetter, Christian A1 - Raslan, Furat A1 - Vinc, Giles Hamilton A1 - Ernestus, Ralf-Ingo T1 - Brain edema formation correlates with perfusion deficit during the first six hours after experimental subarachnoid hemorrhage in rats N2 - Background: Severe brain edema is observed in a number of patients suffering from subarachnoid hemorrhage (SAH). Little is known about its pathogenesis and time-course in the first hours after SAH. This study was performed to investigate the development of brain edema and its correlation with brain perfusion after experimental SAH. Methods: Male Sprague–Dawley rats, randomly assigned to one of six groups (n = 8), were subjected to SAH using the endovascular filament model or underwent a sham operation. Animals were sacrificed 15, 30, 60, 180 or 360 minutes after SAH. Intracranial pressure (ICP), mean arterial blood pressure (MABP), cerebral perfusion pressure (CPP) and bilateral local cerebral blood flow (LCBF) were continuously measured. Brain water content (BWC) was determined by the wet/dry-weight method. Results: After SAH, CPP and LCBF rapidly decreased. The decline of LCBF markedly exceeded the decline of CPP and persisted until the end of the observation period. BWC continuously increased. A significant correlation was observed between the BWC and the extent of the perfusion deficit in animals sacrificed after 180 and 360 minutes. Conclusions: The significant correlation with the perfusion deficit after SAH suggests that the development of brain edema is related to the extent of ischemia and acute vasoconstriction in the first hours after SAH. KW - Medizin KW - Subarachnoid hemorrhage KW - Cerebral blood flow KW - Brain ischemia KW - Brain edema KW - Animal models Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-75765 ER -