Chronic potassium depletion and sensitivity to tubocurarine.
The effect of low potassium diets with and without deoxycorticosterone (DOCA), furosemide, chlorothiazide, or ethacrynic acid on sensitivity of isolated guinea pig lumbrical nerve-muscle preparations to d-tubocurarine was examined. The ED50 of d-tubocurarine was found to fall as the potassium level was lowered by dietary restriction. Addition of DOCA or furosemide was without effect while chlorothiazide reduced and ethacrynic acid enhanced the effect of diet alone. Acute restoration of potassium levels of 5.9 mM reversed considerably, but not completely, the effect of chronic depletion. Thus, a patient suffering from chronic potassium depletion would be expected to require a decreased dose of d-tubocurarine, and although acute replacement of potassium preoperatively would tend to return the dose requirement toward normal, such reversal might not be complete.
D000818:Animals; D002908:Chronic Disease; D003900:Desoxycorticosterone / Q000494:pharmacology; D004032:Diet; D004232:Diuretics / Q000494:pharmacology; D006168:Guinea Pigs; D007008:Hypokalemia / Q000139:chemically induced / Q000209:etiology / Q000503:physiopathology*; D066298:In Vitro Techniques; D009119:Muscle Contraction / Q000187:drug effects; D009469:Neuromuscular Junction / Q000187:drug effects; D011188:Potassium / Q000008:administration & dosage; D014403:Tubocurarine / Q000494:pharmacology*
D004232:Diuretics; D003900:Desoxycorticosterone; D011188:Potassium; D014403:Tubocurarine