Rapid Direct Effects of Castration and Androgen Treatment on Luteinizing Hormone-Releasing Hormone-Induced Luteinizing Hormone Release in the Phenobarbital-Treated Male Rat: Examination of the Roles Direct and Indirect Androgen Feedback Mechanisms Might Play in the Physiological Control of Luteinizing Hormone Release*
| Autor: | W. H. Meinzer, D. D. Nansel, M. S. Aiyer, E. M. Bogdanove |
|---|---|
| Rok vydání: | 1979 |
| Předmět: |
Male
endocrine system medicine.medical_specialty Pituitary gland medicine.drug_class Gonadotropin-releasing hormone Feedback Gonadotropin-Releasing Hormone Andrology chemistry.chemical_compound Endocrinology Internal medicine medicine Animals Castration Orchiectomy business.industry Dihydrotestosterone Luteinizing Hormone Androgen Rats Kinetics medicine.anatomical_structure chemistry Phenobarbital Luteinizing hormone business hormones hormone substitutes and hormone antagonists medicine.drug Hormone |
| Zdroj: | Endocrinology. 104:524-531 |
| ISSN: | 1945-7170 0013-7227 |
| DOI: | 10.1210/endo-104-2-524 |
| Popis: | Adult male rats, given phenobarbital (PB) to suppress their endogenous LH-releasing activity, were used to test whether orchidectomy and dihydrotesterone (DHT) treatment and withdrawal could act acutely to modify the pituitary LH release response to exogenous LHRH infusion. When LHRH was infused at a constant rate of 15 or 45 ng/h beginning immediately after orchidectomy, castrates and sham-castrated controls responded similarly for up to 18 h. However, when the LHRH infusion rate was abruptly changed from 15 to 45 ng/h 4 h postoperatively, castrates developed greater serum LH levels than uncastrated controls. Castration (the withdrawal of testicular feedback signals) appeared to have increased the ability of the pituitary to respond to an increment in the LHRH infusion rate. This effect of orchidectomy was reduced in rats given DHT by sc implantation at the time of castration, using doses of DHT equal to or less than those needed to prevent the orchidectomyinduced increase in circulating LH in the absenc... |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|