Consequences of chronic K+ depletion for the ionic composition of brain, heart, skeletal muscle and cerebrospinal fluid.
Chronic dietary K+ depletion was induced in rats for up to 90 days. The treatment induced hypokalemia, moderate hypernatremia, and moderate metabolic alkalosis which was partly compensated for by a hyperproteinemic acidosis at an unchanged arterial PCO2. Whereas the K+ content of skeletal muscle was reduced to almost half its regular content, the heart muscle was much less affected and the brain K+ content was minimally reduced or not affected depending on the duration of the K+ depletion. The reduction in muscle tissue K+ content was not fully compensated for by an increase in Na+ content. Cerebrospinal fluid K+ and H+ concentrations were decreased during K+ depletion. This may explain the decreased cerebral blood flow measured during K+ depletion at an unchanged cerebral metabolic rate for glucose.
Schröck
H
H
Physiologisches Institut, Universität Bonn, BRD.
Kuschinsky
W
W
D000818:Animals; D001923:Brain Chemistry; D002560:Cerebrovascular Circulation; D004032:Diet; D004573:Electrolytes / Q000097:blood / Q000134:cerebrospinal fluid / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D008297:Male; D009132:Muscles / Q000378:metabolism*; D009206:Myocardium / Q000378:metabolism*; D011191:Potassium Deficiency / Q000097:blood / Q000134:cerebrospinal fluid / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D012964:Sodium / Q000097:blood / Q000134:cerebrospinal fluid; D014882:Water-Electrolyte Balance
D004573:Electrolytes; D012964:Sodium