Effects of Ghrelin on Testosterone Release in Type 1 Diabetic Rats
| Autor: | Chia-Hsin Chang, 張家馨 |
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| Rok vydání: | 2013 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 101 Ghrelin, an acylated peptide consisting of 28 amino acids, is synthesized predominantly in the stomach but has also been identified in a variety of other organs, such as bowels, kidney, thyroid, lung, lymphatic tissue, placenta, hypothalamus, pituitary and gonads. Ghrelin was detected in both rat and human testes, predominantly in interstitial Leydig cells. In addition, increasing evidence suggests that ghrelin could also be involved in the control of gonadal function. The previous findings suggested that ghrelin level is reduced in the diabetes mellitus (DM). In this study, male rats were treated with or without streptozotocin (STZ, 50 mg/kg, i.v.). The STZ-induced type I DM rats were injected with or without ghrelin (10 μg/ml/kg, i.v.) once daily for 7 days before decapitation. The control rats were injected with vehicle. After decapitation, rat blood samples were collected. The Leydig cells were prepared by continuous percoll gradient method, and then incubated with or without human chorionic gonadotropin (hCG, 0.05 IU/ml), 8-bromo-cyclic 3’:5’-adenosine monophosphate (8-Br-cAMP, a permeable analog of cAMP, 10-4 M), forskolin (an adenylyl cyclase activator, 10-5 M), at 37℃ for 1 hour. The concentrations of testosterone in rat plasma and medium samples were measured by radioimmunoassay. Although the level of plasma testosterone was reduced in diabetic rats, administration of ghrelin (10 μg/ml/kg) for 7 days resulted in a significant increase (p |
| Databáze: | Networked Digital Library of Theses & Dissertations |
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