OCTREOTIDE AND POTASSIUM HOMEOSTASIS

Somatostatin infusion causes hyperkalemia in healthy subjects and in s ome animal models. The purpose of this investigation was to determine what effect octreotide has on potassium homeostasis during serious ill ness and if there is a dose-response relationship. Sixty-six male Spra gue-Dawley rats (185-225 g) were randomized to receive parenteral nutr ition (PN) only PN plus continuous infusion of Escherichia coli lipopo lysaccharide (LPS), or PN plus LPS plus octreotide 10, 100, or 1000 mu g/kg/day for 48 hours. Before randomization all animals received isoc aloric, isonitrogenous, isokalemic PN. A 24-hour urine was collected a nd a blood sample was taken at the end of the study immediately before euthanization. Data were analyzed by ANOVA and Duncan's multiple rang e lest. Nonhemolyzed serum samples from 50 rats were available for stu dy. Serum potassium concentrations were in the normal range for rats a nd did not differ significantly among the groups: 5.97 +/- 0.86, 5.96 +/- 1.58, 5.78 +/- 1.48, 5.79 +/- 1.67, 5.35 +/- 0.78 mEq/L, respectiv ely. No differences among groups were found for fractional excretion o f potassium or serum creatinine concentration. Octreotide administrati on in escalating dosages does not cause hyperkalemia in endotoxemic ra ts given intravenous potassium at a constant rate by PN.