[Urinary LHRH: radioimmunological assay and physiological significance]

A LHRH-like substance is detectable in the urine. It is extractable by glass powder, which suggests that it is a peptide, and it can be concentrated by anti-LHRH affinity chromatography, strongly suggesting that it is not a contaminant in the RIA. It is composed of very little intact LHRH, and the great majority appears as multiple smaller fractions, although the possibility of "urinary LHRH" being a slightly larger peptide containing a sequence similar or identical to that of LHRH has not been entirely eliminated. Urinary measurements show no correlation with the clinical state, and the widely differing values obtained using different antisera in the present study emphasize the need for in-depth antiserum binding studies prior to clinical use in the LHRH radioimmunoassay.