Studies with Synthetic LH-Releasing Hormone in the Human

Abstract

Synthetic LRH was injected i.v. innormal menstruating women and in patients with various endocrine disorders, such as retarded growth, precocious onset of puberty, anovulation, secondary amenorrhea, Sheehan’s syndrome, menopause, cryptorchidism, and Klinefelter’s syndrome. A linear log dose response relationship for LH release was found after injection of 12.5, 25, and 50 µg and, for FSH release, following injection of 6, 12, and 24 µg LRH. Maximal LH responses to a given test dose of 25 µg LRH in eu- and amenorrheal women differed significantly (p < 0.05). No difference in LH peak occurrence time was noted between the two groups. In 8 out of 120 individuals, no LH release was detected, e.g., in Sheehan’s syndrome and in retarded growth. In hypogonadal and hypergonadotropic subjects, an overresponsiveness of the pituitary to LRH stimuli was noted. Overresponsiveness was also observed in a peripubertal girl. The data presented support the concept of the pituitary sensitivity to exogenous LRH depending on the degree of endogenous gonadotropin releasing hormone stimulation.