Effects of reserpine on protective function of diazepam against hyperbaric oxygen-induced convulsions

The rats treated 24 hours previously with ip reserpine (5 mg/kg) were exposed to hyperbaric oxygen (HBO 456 kPa, 25 min) in order to deplete monoamine neurotransmitters in the brains. NE, DA and 5-HT levels in brain were decreased. The incidence and latency of HBO-induced convulsions were similar to the control group that had been exposed to HBO alone. After the rats were treated with reserpine and then ip diazepam (750 μg/kg), NE, DA and 5-HT levels in brain were markedly lowered. However, the protective function of diazepam was unaffected. The authors consider it necessary to hold that the contents of monoamine neurotransmitters are neither involved in HBO-induced seizures, nor in the protective function of GABA.