CLEARANCE AND IDENTIFICATION OF THYROTROPHIN RELEASING HORMONE IN HUMAN URINE AFTER INTRAVENOUS INJECTIONS

Abstract

The urine clearance of TRH after intravenous injection in man has been measured by radioimmunoassay. Between 4.4 percent and 10.7 percent of the dose was excreted within 90 min, the majority within 30 min. The TRH excreted was immunochemically and chromatographically indistinguishable from synthetic TRH and was inactivated by plasma enzymes with the same kinetic characteristics. The immunoreactive TRH-like material in basal urine samples was not TRH however: chromatographically and enzymatically it behaved differently from the synthetic tripeptide.