Vyskocil F, Zemková H, Teisinger J, Svoboda P
Institute of Physiology, Czechoslovak Academy of Sciences, Praha.
Brain Res. 1987 Dec 8;436(1):85-91. doi: 10.1016/0006-8993(87)91559-9.
Arachidonate 5 x 10(-5) mol.l-1 increased the rate of hyperpolarization induced in Na+-loaded mouse diaphragm fibers by 5 mmol.l-1 K+. When applied to Na+-loaded muscles without potassium, arachidonate 1 x 10(-6) and 5 x 10(-5) mol.l-1 induced a ouabain-sensitive hyperpolarization of the muscle fibers. The activity of rat brain microsomal Na+,K+-ATPase was stimulated by 1 x 10(-7)-5 x 10(-6) mol.l-1 arachidonate in reaction media with reduced amounts of ATP or K+ and after short-lasting sonication of the samples. It was concluded that, under particular conditions, arachidonate might serve as a Na+,K+-ATPase activator or inhibitor regulating its ion transport and electrogenicity.
