Showing papers by "Robert L. Reid published in 1984"

Evidence for decreased endogenous dopamine and opioid inhibitory influences on LH secretion in polycystic ovary syndrome.

Abstract: SUMMARY The inhibitory role of the dopaminergic and opioidergic mechanisms in the control of LH secretion in patients with polycystic ovary syndrome (PCO) was evaluated. The administration of an opiate receptor antagonist, naloxone, of a dopamine receptor antagonist, metoclopramide, or of human synthetic βh-endorphin, were unable to alter LH secretory activity in patients with PCO. Since identical doses of these antagonists and the opiate agonist have elicited respectively a rise and fall of LH levels in normal cycling women, these findings suggest that an underlying hypothalamic component of defect in endogenous dopamine and opioid control may be responsible for the inappropriate gonadotrophin secretion in this syndrome.

Gonadotropin-Releasing Activity of of α-Melanocyte-Stimulating Hormone in Normal Subjects and in Subjects with Hypothalamic-Pituitary Dysfunction

Abstract: The gonadotropin-releasing activity of synthetic alpha MSH, previously found in normal men, was evaluated in women with different hormonal environments and in patients with acyclic gonadotropin release due to hypothalamic-pituitary dysfunction. alpha MSH (2.5 mg, iv) administered as either a single or two repeated pulses (at 2-h intervals) elicited unequivocal pituitary release of LH in normal women during the luteal phase and midcycle surge and in patients with functional hypothalamic amenorrhea, hyperprolactinemic amenorrhea, and polycystic ovary syndrome. Concomitant release of LH and FSH occurred only in polycystic ovarian syndrome patients and normal men. alpha MSH had no discernible effect on gonadotropin release in women during the early and late follicular phases of the cycle, in postmenopausal women, and in patients with isolated gonadotropin deficiency, even after pulsatile GnRH priming. The present observations confirm and extend our earlier finding that alpha MSH possesses gonadotropin-releasing activity in men and indicate that alpha MSH has similar properties in women with progesterone- and androgen-dominated environments or with specific types of hypothalamic-pituitary dysfunction marked by attenuated GnRH-LH release.