Studies on some neuropharmacological properties of Nevirapine in mice

Nevirapine (NVP) is non-nucleoside reverse transcriptase inhibitor and an anti-retroviral drug (ARV) with the highest BBB penetrating ability. Its specific pharmacologic effects on central nervous system (CNS) are not well known. The objective of the study was to investigate some CNS effects of Nevirapine. Oral acute toxicity test (Lorke, 1983) was used to estimate the LD₅₀. Exploratory or sedative effects were tested using open field test(OFT), Hole-board test (HBT), diazepam-induced sleeping time test, and ketamine-induced sleeping time test. Five groups of mice were used (5 mice /group). The negative control group received vehicle (distilled water) (10 mL /kg) while groups II, III, and IV received NVP- 15.625 mg/kg, 31.25 mg/kg, 62.5 mg/kg body weight respectively while group V received 0.25 mg/kg of diazepam intraperitoneal. Groups I to IV were treated orally. The oral LD₅₀ was determined to be 2154. 07 mg/kg. NVP, in a dose dependent fashion, increased the number of line-crossing in the OFT. Also, NVP in a dose-dependent fashion, significantly reduced the duration of diazepam-induced sleeping time as well as delayed onset. NVP significantly potentiated ketamine-induced sleeping time duration. Nevirapine possess excitatory effects possibly through antagonism of GABA receptors. Nevirapine causes wakefulness (shortening of sleep) possibly via antagonism of GABAergic neurotransmission.