Effects of general anaesthetics on the activity of the Na,K-ATPase of canine renal medulla.
Several previous studies have reported inhibition of Na,K-ATPase activity by chlorpromazine, phenobarbital and pentobarbital, thiopental, and monoketones. The purpose of this study is to investigate the influences of other general anaesthetics on Na,K-ATPase activity. The ATPase activity of Na,K-ATPase-enriched membranes from canine renal medulla was determined at 37 degrees C in the absence and in the presence of hexanol, diethylether, halothane, and propofol. The influence of hexanol on stimulation of Na,K-ATPase activity by Na+ and K+ was investigated. Hexanol, diethylether, halothane, and propofol inhibited the activity at 37 degrees C of the Na,K-ATPase of canine renal medulla. The IC50 values at 37 degrees C were: hexanol, 12.3 mM; diethylether, 170 mM; halothane, 7.35 mM; propofol, 0.127 mM. Hexanol increased the K0.5 of the Na,K-ATPase for K+ at 37 degrees C, but did not affect the K0.5 for Na+. At lower [K+] hexanol was a more potent inhibitor than at higher [K+].
Kutchai
H
H
Department of Molecular Physiology and Biological Physics, School of Medicine, University of Virginia, Charlottesville 22906, USA.
Geddis
L M
LM
Farley
R A
RA
D000777:Anesthetics / Q000494:pharmacology*; D000818:Animals; D004285:Dogs; D004986:Ether / Q000494:pharmacology; D006221:Halothane / Q000494:pharmacology; D000441:Hexanols / Q000494:pharmacology; D007679:Kidney Medulla / Q000201:enzymology*; D011188:Potassium / Q000494:pharmacology; D015742:Propofol / Q000494:pharmacology; D012964:Sodium / Q000494:pharmacology; D000254:Sodium-Potassium-Exchanging ATPase / Q000037:antagonists & inhibitors*
D000777:Anesthetics; D000441:Hexanols; D004986:Ether; C036260:1-hexanol; D012964:Sodium; D000254:Sodium-Potassium-Exchanging ATPase; D011188:Potassium; D006221:Halothane; D015742:Propofol