Effects of n-propyl gallate on neuronal survival after forebrain ischemia in rats.

The present study was conducted to assess the effects of intraperitoneal administration of n-propyl gallate (PG) on hippocampal neuronal survival after forebrain ischemia. Forty male Sprague-Dawley rats were randomly assigned to one of 6 groups. Animals in the PG-I-10, PG-I-8 and PG-S groups received intraperitoneal injection of PG (100mg/kg) 72, 48, 24h and 30 min before severe (10 min) or moderate (8 min) ischemia or sham operation, respectively, while animals in the V-I-10, V-I-8 and V-S groups received the vehicle (10% DMSO) in the same manner. Forebrain ischemia was produced by bilateral carotid occlusion combined with hypotension (35 mmHg) under isoflurane anesthesia. Animals were killed 7 days after reperfusion. Histological assessments were performed using hematoxylin and eosin staining. In separate groups of animals that received PG or vehicle, m-RNA levels of hypoxia-inducible factor 1α (HIF-1α), erythropoietin (EPO) and vascular endothelial growth factor (VEGF) were measured using the reverse transcription-PCR protocol. The number of normal neurons was significantly higher in the PG-I-8 group compared with that in the V-I-8 group, whereas it was similar between the PG-I-10 and V-I-10 groups. Animals that received PG had significantly higher levels of HIF-1α, EPO and VEGF expression compared with those that received vehicle. The results indicated that intraperitoneal administration of PG may have neuroprotective effects in a model of moderate, but not severe, forebrain ischemia in rats.