Inhibition of hippocampal acetylcholine release by benzodiazepines: antagonism by flumazenil.
Diazepam (2.5-10 mg/kg i.p.) and midazolam (2.5-10 mg/kg i.p.) decreased acetylcholine release in the hippocampus of freely moving rats. This effect was antagonized by pretreatment with flumazenil (1 mg/kg i.p.). These results show that activation of benzodiazepine receptors reduces the in vivo release of acetylcholine in the hippocampus, suggesting that the septo-hippocampal cholinergic system, which has a major role in the regulation of cognitive functions, is under inhibitory control exerted by gamma-aminobutyrate (GABA) neurons.
Imperato
A
A
Department of Neuroscience Bernard B. Brodie, University of Cagliari, Italy.
Dazzi
L
L
Obinu
M C
MC
Gessa
G L
GL
Biggio
G
G
D000109:Acetylcholine / Q000378:metabolism*; D000704:Analysis of Variance; D000818:Animals; D003975:Diazepam / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D004347:Drug Interactions; D005442:Flumazenil / Q000494:pharmacology*; D006624:Hippocampus / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D008874:Midazolam / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley
D005442:Flumazenil; D000109:Acetylcholine; D003975:Diazepam; D008874:Midazolam