CIRCULATING LUTEINIZING-HORMONE RECEPTOR INHIBITOR(S) IN BOYS WITH CHRONIC-RENAL-FAILURE

Patients with chronic renal failure frequently have hypogonadism. To e lucidate the molecular mechanisms involved, we tested the ability of s erum from these patients to inhibit recombinant human luteinizing horm one receptors. Using a cell line expressing functional human luteinizi ng hormone receptors, we found that adenosine 3',5'-monophosphate (cAM P) production was markedly inhibited by sera from the patients, but no t by sera from healthy subjects. Inhibition of cAMP production was ass ociated with inhibition of I-125-human chorionic gonadotropin binding. Inhibition of LH receptors by sera from patients correlated with the glomerular filtration rate and after renal allograft transplantation, decreased. Fractionation of serum samples indicated the receptor-inhib iting activity in proteins of molecular weights from 30,000 to 60,000 Daltons. When characterized and purified, the factor responsible may w ell be a new LH receptor antagonist of clinical significance.