Responses of photosensitive and photorefractory male white-crowned sparrows (Zonotrichia leucophrys gambelii) to synthetic mammalian luteinizing hormone releasing hormone (syn-LHRH)
| Autor: | John C. Wingfield, Philip W. Matfocks, Joe William Crim, Donald S. Farner |
|---|---|
| Rok vydání: | 1979 |
| Předmět: |
Male
medicine.medical_specialty Periodicity Adult male Light medicine.medical_treatment Birds Gonadotropin-Releasing Hormone Pituitary Gland Anterior Internal medicine medicine Animals Saline Zonotrichia leucophrys gambelii biology Zonotrichia Cell Biology General Medicine Plasma levels Luteinizing Hormone biology.organism_classification White (mutation) Endocrinology Reproductive Medicine Seasons Luteinizing hormone Hormone |
| Zdroj: | Biology of reproduction. 21(4) |
| ISSN: | 0006-3363 |
| Popis: | To assess a possible role of the adenohypophysis in photorefractoriness, photosensitive and photorefractory adult male white-crowned sparrows (Zonotrichia Ieucophrys) were treated with single intravenous injections of 0, 0.5, 5, 20, 35, 50 or 500 ng of synthetic Iuteinizing hormone releasing hormone (Syn-LHRH) in 0.9% saline solution. Serial samples of plasma were taken immediately before and at 5, 20 and 60 mm after injection. The plasma level of immunoreactive luteinizing hormone (irLH) was not altered by the injection of saline solution alone, or by 0.5 or 5 ng Syn-LHRH in either photosensitive or photorefractory birds. Treatment with 20, 35, 50 or 500 ng Syn-LHRH, however, elicitedsignificant and approximately equal increases in plasma levels of irLH in both groups 5 mm after injection. These responses are consistent with the hypothesis that the site of photorefractoriness is at a level higher than the adenohypophysis. |
| Databáze: | OpenAIRE |
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