title: Beta-adrenergic-mediated extrarenal potassium disposal in patients with end-stage renal disease: effect of propranolol.
abstract: This study was designed to investigate beta-adrenergic-mediated extrarenal potassium disposal in patients with end-stage renal disease (ESRD). Plasma potassium was measured over a period of 3 months in 20 patients with ESRD who were receiving the nonselective beta-blocker propranolol (n = 10) or not (n = 10). Both groups were virtually anuric and had a comparable plasma BUN, plasma bicarbonate, and red cell Na-K-ATPase activity. Plasma potassium measured before dialysis was higher in propranolol users than in nonusers (5.6 +/- 0.2 and 4.6 +/- 0.1 mEq/l, p less than 0.005). To examine beta-adrenergic-mediated internal potassium disposal more directly, epinephrine and epinephrine plus propranolol were acutely administered to another group of patients with ESRD and to normal subjects. Epinephrine resulted in a similar fall in plasma potassium in both groups (0.69 +/- 0.20 and 0.63 +/- 0.07 mEq/l, respectively), thereby suggesting unimpaired beta-adrenergic-mediated extrarenal potassium handling in patients with ESRD. In patients, however, the response to epinephrine was heterogeneous. In 4 of the 10 patients studied, epinephrine infusion did not result in a decrement in plasma potassium suggesting impaired beta-adrenergic responsiveness and thus blunting of this mechanism of extrarenal potassium disposal. In the remaining 6 patients, epinephrine infusion resulted in a fall in plasma potassium which was greater than that observed in normal subjects (1.13 +/- 0.14 and 0.63 +/- 0.07 mEq/l, respectively, p less than 0.01). In the presence of propranolol, the infusion of epinephrine did not result in a decrement in plasma potassium in these 6 patients or in the 6 normal subjects (0.04 +/- 0.07 and -0.02 +/- 0.06 mEq/l, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)
authors.forename: W C
authors.initials: WC
authors.lastname: Yang
authors.forename: T P
authors.initials: TP
authors.lastname: Huang
authors.forename: L T
authors.initials: LT
authors.lastname: Ho
authors.forename: H M
authors.initials: HM
authors.lastname: Chung
authors.forename: Y L
authors.initials: YL
authors.lastname: Chan
authors.forename: D C
authors.initials: DC
authors.lastname: Batlle
mesh_terms: D000319:Adrenergic beta-Antagonists / Q000494:pharmacology* / Q000627:therapeutic use; D000328:Adult; D000368:Aged; D004347:Drug Interactions; D004837:Epinephrine / Q000008:administration & dosage / Q000494:pharmacology; D005260:Female; D006801:Humans; D007008:Hypokalemia / Q000188:drug therapy / Q000378:metabolism; D007263:Infusions, Parenteral; D007676:Kidney Failure, Chronic / Q000188:drug therapy / Q000378:metabolism* / Q000628:therapy; D008297:Male; D008875:Middle Aged; D011188:Potassium / Q000097:blood / Q000378:metabolism*; D011433:Propranolol / Q000008:administration & dosage / Q000494:pharmacology*; D006435:Renal Dialysis
chemical_list: D000319:Adrenergic beta-Antagonists; D011433:Propranolol; D011188:Potassium; D004837:Epinephrine