Isoflurane--a study of its adrenoceptor interaction in the isolated rat parotid gland.
Adrenergic receptor interaction with isoflurane was studied in an in vitro rat parotid gland model in which beta-adrenoceptor agonists evoke amylase release and alpha-adrenoceptor agonists induce potassium secretion from parotid cells. The amylase secretory studies were performed using a batch-incubation technique, and potassium efflux was evaluated using 86Rb+ as a probe for K+. Isoflurane was dissolved in a fat emulsion, which of its own had no secretory effect. Isoflurane induced a dose-dependent amylase release that was unaffected by beta-adrenergic blockade with propranolol and metoprolol. Isoflurane also induced a significant efflux of 86Rb+ that could not be inhibited by the alpha-adrenoceptor antagonist, phentolamine. Dinitrophenol, an uncoupler of oxidative phosphorylation, had no effect on the isoflurane-induced enzyme release, indicating that amylase secretion occurred by passive leakage. It is suggested that isoflurane has no direct action on alpha- or beta-adrenoceptors. Isoflurane, however, induces potent cellular events that might be due to an unspecific effect on the cell membrane, thereby causing changes in membrane permeability.
D019297:2,4-Dinitrophenol; D000681:Amylases / Q000378:metabolism; D000818:Animals; D004140:Dinitrophenols / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D005260:Female; D007530:Isoflurane / Q000494:pharmacology*; D008738:Methyl Ethers / Q000494:pharmacology*; D008790:Metoprolol / Q000494:pharmacology; D010085:Oxidative Phosphorylation / Q000187:drug effects; D010306:Parotid Gland / Q000378:metabolism*; D011188:Potassium / Q000378:metabolism; D011433:Propranolol / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D011941:Receptors, Adrenergic / Q000378:metabolism*; D012413:Rubidium / Q000378:metabolism
D004140:Dinitrophenols; D008738:Methyl Ethers; D011941:Receptors, Adrenergic; D011433:Propranolol; D007530:Isoflurane; D000681:Amylases; D008790:Metoprolol; D012413:Rubidium; D019297:2,4-Dinitrophenol; D011188:Potassium