Plasma gonadotropins after administration of lh-releasing hormone in patients with renal or hepatic failure

The pituitary gonadotropin response to the administration of synthetic LH releasing hormone (LH RH) in 10 patients with renal failure and 5 patients with hepatic insufficiency was determined. The basal plasma LH and FSH levels were either normal or slightly elevated in both groups compared with the controls, but after the administration of LH RH, the peak levels (mean ± (SE) mIU/ml) of LH (72.0 ± 16.6) and FSH (18.7 ± 4.4) in the patients with renal failure, and of LH (61.5 ± 20.8) and FSH (13.2 ± 2.8) in patients with hepatic insufficiency, were not significantly different from those in 11 normal controls (LH, 75.6 ± 12.0; FSH, 12.4 ± 2.9). However, significant elevations in plasma gonadotropin levels persisted in these patients during the second and third hours after the administration of LH RH. These studies do not resolve the question of whether the prolonged elevation in plasma LH and FSH levels after LH RH administration is due to enhanced secretion, to a diminished rate of metabolic clearance of LH RH, and/or to the gonadotropins, or both. Evidence from this and previous studies suggest that there may be defects in the secretory functions of both the hypothalamus and pituitary gland in some of these patients.