Evidence for Adrenal Involvement in the Modulatory Role of Prolactin in Luteinizing Hormone Secretion in the Male Rat*
- 1 April 1979
- journal article
- research article
- Published by The Endocrine Society in Endocrinology
- Vol. 104 (4) , 948-953
- https://doi.org/10.1210/endo-104-4-948
Abstract
Adrenalectomized and non-adrenalectomized male rats were studied to evaluate the interplay of PRL and the adrenal in the regulation of LH secretion during hyperprolactinemia. Hyperprolactinemia was induced by transplantation of pituitaries beneath the kidney capsule or by exogenous administration. Basal serum LH levels were significantly reduced (P < 0.5) in adult male rats (>90 days of age) bearing ectopic pituitaries. Pituitary LH release after 10 but not 20 ng LHRH, in the presence or absence of the adrenal, was blunted (P < 0.05) during hyperprolactinemia. Furthermore, chronic hyperprolactinemia slightly suppressed the rise in serum LH after gonadectomy, whereas LH secretion after 20 ng LHRH was markedly diminished in the castrated, hyperprolactinemic male rat, effects which were independent of the presence of the adrenal. Acute hyperprolactinemia (6 h) in the presence but not in the absence of the adrenal in the adult male rat significantly inhibited the LH response to 20 ng LHRH. In the youn postpubertal male rat (45–55 days of age), acute hyperprolactinemia (18 h) inhibited LH release in response to LHRH, an effect, however, mediated entirely via the adrenal. Unlike the adult male rat, acute hyperprolactinemia in the absence of the adrenal elevated basal serum LH levels and sensitized the pituitary to exogenous LHRH.Keywords
This publication has 7 references indexed in Scilit:
- Suppression of Plasma Luteinizing Hormone by Prolactin in the Male RatEndocrinology, 1978
- A Comparison of Pituitary Responsiveness to Luteinizing Hormone-Releasing Hormone during Lactation and the Estrous Cycle of the Rat*Endocrinology, 1978
- Effects of Prolactin (PRL) on Pituitary and Testicular Function in Mice with Hereditary PRL DeficiencyEndocrinology, 1977
- Inhibition ofin VivoPituitary Release of Luteinizing Hormone in Lactating Rats by Exogenous ProlactinEndocrinology, 1977
- ANTIGONADOTROPHIC EFFECT OF PROLACTIN IN ADULT CASTRATED AND IN IMMATURE FEMALE RATSActa Endocrinologica, 1977
- Effects of Experimentally-Induced Chronic Hyperprolactinemia on Testosterone and Gonadotropin Levels in Male Rats and MiceEndocrinology, 1977
- Effects of Suckling on Hypothalamic LH-Releasing Factor and Prolactin Inhibiting Factor, and on Pituitary LH and ProlactinEndocrinology, 1967