title: Acetylcholine release induced by the volatile anesthetic sevoflurane in rat brain cortical slices.
abstract: 1. We have investigated the effect of the volatile anesthetic sevoflurane on acetylcholine (ACh) release from rat brain cortical slices. 2. The release of [3H]-ACh into the incubation fluid was studied after labeling the tissue ACh with [methyl-3H]-choline chloride. 3. We observed that sevoflurane induced an increase on the release of ACh that was dependent on incubation time and anesthetic concentration. The sevoflurane-induced ACh release was not blocked by tetrodotoxin (TTX) and therefore was independent of sodium channels. In addition, the sevoflurane effect was not blocked by ethylene glycol-bis(beta-aminoethyl ether (EGTA) or cadmium (Cd2+), thus independent of extracellular calcium. 4. The sevoflurane-induced ACh release was inhibited by 1,2-bis (2-aminophenoxy) ethane-N,N,N',N'-tetra-acetic acid (BAPTA-AM), suggesting the involvement of intracellular calcium-sensitive stores in the process. Dantrolene, an inhibitor of ryanodine receptors, had no effect but 2-aminoethoxydiphenylborate (2-APB), a membrane-permeable inhibitor of inositol 1,4,5-triphosphate receptor inhibited the sevoflurane-induced release of ACh. 5. It is concluded that sevoflurane-induced release of ACh in brain cortical slices involves the mobilization of calcium from IP3-sensitive calcium stores.
authors.affiliation: Departamento de Morfologia, ICB-UFMG, Belo Horizonte-Minas Gerais, Brazil.
authors.forename: Janice H
authors.initials: JH
authors.lastname: Silva
authors.forename: Renato S
authors.initials: RS
authors.lastname: Gomez
authors.forename: Ana Cristina N
authors.initials: AC
authors.lastname: Pinheiro
authors.forename: Marcus V
authors.initials: MV
authors.lastname: Gomez
authors.forename: Cristina
authors.initials: C
authors.lastname: Guatimosim
mesh_terms: D000109:Acetylcholine / Q000493:pharmacokinetics*; D018685:Anesthetics, Inhalation / Q000494:pharmacology*; D000818:Animals; D002118:Calcium / Q000378:metabolism; D002540:Cerebral Cortex / Q000187:drug effects* / Q000378:metabolism; D005260:Female; D008297:Male; D008738:Methyl Ethers / Q000494:pharmacology*; D009924:Organ Culture Techniques; D051381:Rats; D017208:Rats, Wistar; D000077149:Sevoflurane; D009435:Synaptic Transmission / Q000187:drug effects; D014316:Tritium
chemical_list: D018685:Anesthetics, Inhalation; D008738:Methyl Ethers; D014316:Tritium; D000077149:Sevoflurane; D000109:Acetylcholine; D002118:Calcium