Effects of diazepam on adenosine and acetylcholine release from rat cerebral cortex: further evidence for a purinergic mechanism in action of diazepam.
1 Diazepam administered intraperitoneally (0.25 mg/kg) enhanced the rate of efflux of [3H]-adenosine and its metabolites from rat cerebral cortex. At a lower dose (0.05 mg/kg), this effect could be detected in only one of four rats. 2 Diazepam (0.05 and 0.25 mg/kg i.p.) depressed acetylcholine release from the rat cerebral cortex. Its effect was reversed by theophylline. 3 Theophylline (15 and 30 mg/kg) enhanced acetylcholine release from the rat cerebral cortex. Diazepam (0.25 mg/kg) administered after theophylline failed to cause a reduction in the rate of release, rather there appeared to be a further enhancement of release. 4 Pentobarbitone sodium (5, 10 and 15 mg/kg i.p.) did not elicit any increase in adenosine release. 5 These results support the proposal that benzodiazepines may exert their pharmacological actions by preventing adenosine uptake, thus enhancing the levels of extracellular adenosine.
D000109:Acetylcholine / Q000378:metabolism*; D000241:Adenosine / Q000378:metabolism*; D000818:Animals; D001921:Brain / Q000187:drug effects* / Q000378:metabolism; D003975:Diazepam / Q000494:pharmacology*; D008297:Male; D010424:Pentobarbital / Q000494:pharmacology; D011687:Purines / Q000502:physiology; D051381:Rats; D013806:Theophylline / Q000494:pharmacology
D011687:Purines; D013806:Theophylline; D010424:Pentobarbital; D000241:Adenosine; D000109:Acetylcholine; D003975:Diazepam