Gynecomastia, prolactin, and other peptide hormones in patients undergoing chronic hemodialysis

Gynecomastia was present in 11 of 19 patients undergoing chronic hemodialysis. Blood was drawn immediately before and after dialysis for determination of plasma prolactin (HPr), growth hormone (HGH), thyrotropin (TSH), insulin (IRI) and chemistries. HPr was elevated in seven patients but did not correlate with the gynecomastia nor the simultaneous concentrations of other peptide hormones. Dialysis reduced azotemia, normalized plasma calcium and phosphorus and increased plasma glucose. In association with the latter, IRI rose and HGH fell suggesting that normal feedback relationships for these hormones were preserved. During dialysis, TSH increased to definitely abnormal levels in two subjects; however, elevated HPr fell to normal in only one subject. Thus, the abnormality in HPr is not "driven" acutely by dialyzable solutes. Moreover, the lack of parallelism between HPr and other peptide hormones suggests that the elevated HPr cannot be ascribed simply to a loss of renal degradative loci for peptide hormones.