碩士 / 國立海洋大學 / 水產養殖學系 / 88 / The objectives of the study were to investigate the effects of cold stress on catecholamines, cortisol and immune responses in tilapia (Orechromis aureus). The study was divided into five parts, 1) set up catecholamines assay, induce and purify tilapia IgM antibody, 2) effects of chronic and acute cold stress on catecholamines, cortisol and IgM in tilapia, 3) effects of different stages of acute cold stress on catecholamines, cortisol and IgM in tilapia, 4) in vivo effects of exogenous cortisol, estradiol and catecholamine agonists (phenylephrine and isoproterenol) on cortisol and IgM in tilapia, 5) in vitro effects of cortisol, catecholamines and catecholamine agonists on phagocytosis in tilapia peripherial blood leucocytes.
The results show that : 1) the molecular weight of tilapia IgM is 796 kDa, heavy chain is 77.7 kDa and light chain is 21.8 kDa, 2) the catecholamine levels in brain were not changed after chronic cold stress but norepinephrine levels in hypothalamus decreased after acute cold stress. Increased levels of plasma catecholamine and cortisol, and no effect on plasma IgM levels were observed in fish treated with chronc and acute cold stress. 3) Decrease of norepinephrine levels in hypothalamus and telencepharon was observed in the cold treated group. Catecholamine levels in head kidney were decreased in cold treated group. Increase of plasma catecholamine levels was observed in the process of acute cold stress. There was no affect on plasma IgM level. 4) Plasma IgM levels were decreased after treatment with exogenous high dose of cortisol, isoproterenol and estradiol. 5) Cortisol, high dose of phenylephrine and isoproterenol but not catecholamines could in vitro significantly surppress phagocytosis activity at a dose-dependent manner in tilapia after 4 hours incubation. Actinomycin D and cycloheximide could not block the suppression of isoproterenol on the phagocytosis in tilapia.
| Identifer | oai:union.ndltd.org:TW/088NTOU0086001 |
| Date | January 2000 |
| Creators | Chen wen-hsiung, 陳文雄 |
| Contributors | Chang ching-fong, 張清風 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 81 |
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