Effect of isoproterenol on renal function

The effects on renal function of isoproterenol and vasopressin were compared in conscious hydrated dogs. In response to isoproterenol infusion (12 micrograms/kg/h) urine flow, sodium and potassium excretion, free water clearance dropped markedly whereas glomerular filtration rate, blood flow, and the distribution of cortical blood flow remained practically unaffected. Vasopressin infusion (2 mU/kg/h) produced an antidiuresis comparable to that after isoproterenol infusion, but sodium and potassium excretion was considerably enhanced. Since isoproterenol and vasopressin are known to exert opposing effects on ion excretion, it is suggested that the increased secretion of vasopressin cannot play an exclusive role in the development of changes of renal function induced by isoproterenol.