enkephalin--ala(2)-mephe(4)-gly(5)- and tetrafluoroaluminate

Sevoflurane is widely used for anesthesia, and is commonly used together with opioids in clinical practice. However, the effects of sevoflurane on μ-opioid receptor (μOR) functions is still unclear. In this study, the effects of sevoflurane on μOR functions were analyzed by using Xenopus oocytes expressing a μOR fused to chimeric Gα protein G(qi5) (μOR-G(qi5)). Sevoflurane by itself did not elicit any currents in oocytes expressing μOR-G(qi5), whereas sevoflurane inhibited the [D-Ala(2),N-Me-Phe(4),Gly(5)-ol]-enkephalin (DAMGO)-induced Cl(-) currents at clinically used concentrations. Sevoflurane did not affect the Cl(-) currents induced by AlF(4)(-), which directly led to activation of G proteins. The inhibitory effects of sevoflurane on the DAMGO-induced currents were not observed in oocytes pretreated with the protein kinase C (PKC) inhibitor GF109203X. These findings suggest that sevoflurane would inhibit μOR function. Further, the mechanism of inhibition by sevoflurane would be mediated by PKC.

Topics: Aluminum Compounds; Analgesics, Opioid; Anesthetics, Inhalation; Animals; Enkephalin, Ala(2)-MePhe(4)-Gly(5)-; Female; Fluorides; GTP-Binding Protein alpha Subunits, Gq-G11; Indoles; Maleimides; Methyl Ethers; Oocytes; Patch-Clamp Techniques; Protein Kinase C; Protein Kinase Inhibitors; Receptors, Opioid, mu; Recombinant Fusion Proteins; Sevoflurane; Xenopus laevis