Oscillations of plasma K+ and insulin during K+ infusion in awake anephric dogs.
Changes in plasma potassium ([K+]p) and insulin levels were monitored during K+ infusion in awake and anesthetized nephrectomized, splenectomized dogs. In dogs studied while anesthetized with pentobarbital, the increase in [K+]p was linear, reflecting a nearly constant rate of cellular uptake of the infused K+. In contrast, in dogs studied 18 h after nephrectomy while awake, [K+]p oscillated during infusion, reflecting an inconstant rate of cellular K+ uptake. Although these oscillations in [K+]p were associated with parallel oscillations in plasma insulin levels (suggesting the possibility of a physiological feedback control loop involving K+ and insulin), when the oscillations in insulin levels were blunted by somatostatin infusion or abolished by pancreatectomy plus insulin replacement, oscillations in [K+]p persisted and the average rate of cellular K+ uptake was not diminished. The observed oscillations of [K+]p during K+ infusion suggest the possibility of regulatory control of cellular K+ uptake within the pathophysiologic range of [K+]p. The putative control system is independent of and quantitatively more important than K+-induced insulin secretion and is obscured by pentobarbital anesthesia.
D000818:Animals; D004285:Dogs; D005260:Female; D007263:Infusions, Parenteral; D007328:Insulin / Q000097:blood*; D007700:Kinetics; D008297:Male; D009392:Nephrectomy; D011188:Potassium / Q000008:administration & dosage / Q000097:blood* / Q000494:pharmacology; D014851:Wakefulness
D007328:Insulin; D011188:Potassium