Effects of naloxone infusion on gonadotrophin and prolactin concentrations in patients with chronic renal failure.

Serum prolactin, luteinising hormone and follicle-stimulating hormone, determined by radioimmunoassay were measured during the infusion of 10mg naloxone or saline in eight male patients with chronic renal failure on regular dialysis and in seven normal controls. Neither saline nor naloxone caused any significant change in luteinising hormone, follicle-stimulating hormone or prolactin in patients with chronic renal failure. On the contrary, luteinising hormone secretion was significantly stimulated by naloxone in normal controls. Since naloxone is a specific antagonist of opiate receptors, the results would suggest a reduced hypothalamic opiate tone in patients with chronic renal failure. The data does not support the concept that the high circulating met-encephalin reported in chronic renal failure represents the pathogenetic cause of hyperprolactinaemia in chronic renal failure.