Anesthesia of pentobarbital protects against ischemia induced cell death and rat cortex and cerebellum mitochondrial damage

Abstract

Aim: To investigate the effect of pentobarbital on respiration, calcium induced- mitochondrial permeability transition pore (mPTP) opening of isolated rat brain cortex and cerebellum mitochondria and infarct volume and cell death after 120 min. ischemia in rats. Methods: Brains of adult Wistar male rats were exposed to 120 min. ischemia with/without pentobarbital 40 mg/kg (Dolethal). Respiration of isolated cortical and cerebellar mitochondria was measured oxygraphically using a Oroboros instrument. Ca2+-induced mPTP opening as calcium retention capacity (CRC) was measured using fluorescent dye Calcium Green 5N. Infarct volume was assessed in brain sections of 1 mm thick stained by 2% triphenyl-tetrazolium chloride (TTC). To determine cell death in brain slices of 100 µm was used double fluorescent staining by propidium iodide (PI) and Hoechst. Results: Brain ischemia significantly decreased resistance of isolated cortex and cerebellum mitochondria to calcium-induced mPTP opening and inhibited respiration rate in state 3 with both substrates pyruvate plus malate and succinate. However, pentobarbital before ischemia re-established CRC of both, cortex and cerebellum mitochondria to control level. Pentobarbital also protected against ischemia-induced inhibition of state 3 respiration with pyruvate plus malate and succinate of cortex mitochondria and cerebellum mitochondria only with succinate, while state 3 respiration of cerebellum mitochondria with pyruvate and malate was not changed. Anesthesia with dolethal before ischemia significantly decreased infarct volume and cell death of rat brain after 120 min ischemia. Conclusions: These results demonstrate that anesthesia by pentobarbital protects brain cells against 120 min ischemia-induced cell death reducing inhibition of mitochondrial respiration and sensitivity to calcium-induced mPTP opening.