Preservation of Tropomyosin-Related Kinase B (TrkB) Signaling by Sodium Orthovanadate Attenuates Early Brain Injury After Subarachnoid Hemorrhage in Rats

Recent studies reported that apoptosis was involved in the pathogenesis of early brain injury after subarachnoid hemorrhage (SAH). The aim of this study was to examine whether sodium orthovanadate (SOV) prevents post-SAH apoptosis by modulating growth factors and its downstream receptor tyrosine kinases. Method- Rats were operated on with the endovascular perforation model. SAH animals were treated with vehicle, 3 mg/kg and 10 mg/kg SOV, and evaluated regarding neurofunction and brain edema. The expression of growth factors such as mature brain-derived neurotrophic factor, insulin-like growth factor-1, and vascular endothelial growth factor and phosphorylation of tropomyosin-related kinase B, which is a receptor tyrosine kinase for brain-derived neurotrophic factor and the downstream pathway in antiapoptosis, was examined by Western blot analysis. Neuronal cell death was measured with terminal deoxynucleotidyl transferase-mediated uridine 5'-triphosphate-biotin nick end-labeling staining. We also administered K252a, a tropomyosin-related kinase B antagonist, to examine the mechanisms for neuroprotective effects by SOV.