Effect of glucagon on zinc excretion in anesthetized dogs
Victery, W.; Levenson, R.; Vander, A.J.
American Journal of Physiology 240(4): F299-F305
1981
ISSN/ISBN: 0002-9513 PMID: 7223888 Document Number: 180819
The present studies were performed on anesthetized dogs to determine whether urinary Zn excretion is altered when plasma glucagon concentration is elevated acutely. Glucagon infusion (5 ng .cntdot. kg-1 .cntdot. min-1) adequate to double base-line plasma glucagon significantly increased Zn excretion in a reversible manner; plasma Zn concentration was unchanged. A larger dose of glucagon (50 ng .cntdot. kg-1 .cntdot. min-1) produced no significantly greater effect. Clearance experiments using 65Zn to measure ultrafilterable Zn concentration revealed no change in ultrafilterable Zn during glucagon infusion. In a 3rd series of experiments, acetylcholine (25 .mu.g/min) was infused into 1 renal artery while Zn excretion and renal function of the 2 kidneys were compared. Acetylcholine did not significantly alter Zn excretion despite large changes in Na and water excretion. The changes in Zn excretion observed in all experiments correlated well with glomerular filtration rate changes, but additional contributions of changes in tubular handling of Zn cannot be ruled out.