RENAL TUBULAR EXCRETION OF MERCURIALS IN THE AGLOMERULAR FISH, LOPHIUS AMERICANUS

¹ Departments of Pharmacology, University of Minnesota, Minneapolis, Minnesota, and State University of New York, Upstate Medical Center, Syracuse, New York and Mount Desert Island Biological Laboratory, Salisbury Cove, Maine

Urinary excretion of two mercurial compounds was studied in the aglomerular fish, Lophius americanus. Mercunials were injected intramuscularly into two separate sites rostral to the kidneys. Concentration of Hg²⁰³ appearing in urine collected through catheters placed in the bladder or ureters was compared to concentration in plasma of blood taken from caudal veins . After injection of mersalyl, an acidic mercurial, urine Hg/plasma Hg averaged 19.6; after injection of chlormerodrin, a nonacidic mercurial, urine Hg/plasma Hg averaged 0.51 . The difference was highly significant ( P <.01). Probenecid or p-aminohippurate sharply reduced urine/ plasma ratios that developed when mersalyl was given but did not significantly alter urine/ plasma ratios when chlormerodrin was given . Results indicate that mersalyl is handled by the acid secretory system of the kidney. Chlormerodrin does not appear to be actively transported across renal cells of Lophius.