Neuroprotection With Intraventricular Brain-Derived Neurotrophic Factor in Rat Venous Occlusion Model

Abstract BACKGROUND: The increasing number of neurosurgical procedures for elderly patients and the development of skull base neurosurgery have increased interest in cerebral venous injury that might occur in a neurosurgical setting. Brain-derived neurotrophic factor (BDNF) may have neuroprotective effects against cerebral venous ischemia. OBJECTIVE: To investigate the intraventricular effects of BDNF infusion on infarct size, suppression of apoptosis, and regional cerebral blood flow (rCBF) in cerebral venous ischemic lesions in a rat 2-vein occlusion model. METHODS: Thirty-three male Wistar rats were randomly divided into BDNF-treated and vehicle control groups; each group was further randomly divided into 2-day and 7-day postocclusion groups. BDNF (2.1 μg/day) or vehicle was delivered continuously via intraventricular infusion pumps. Two adjacent contralateral cortical veins were then photochemically occluded. Two and 7 days after occlusion, we histologically measured ratios of infarct volume to contralateral hemisphere volume and counted (2-day group) terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling (TUNEL)-positive apoptotic cells in the penumbra. rCBF was measured via full-field laser perfusion imaging. RESULTS: The mean infarct volume after venous occlusion was significantly smaller in BDNF-treated rats than in controls at 2 days (1.49 ± 1.44% vs 3.66 ± 1.51%; P < .05) and 7 days (0.93 ± 0.47% vs 1.69 ± 0.58%; P < .05). Two days after occlusion, there were significantly fewer TUNEL-positive apoptotic cells in the BDNF-treated rats (17.0 ± 15.1) than in the controls (39.0 ± 19.6; P < .05). There were no differences in rCBF. CONCLUSION: After 2-vein occlusion, continuous intraventricular administration of BDNF protected the cerebral cortex against apoptosis and reduced infarct size without affecting rCBF.