Summary: | 碩士 === 國立臺灣大學 === 生命科學系 === 102 === Water area acidification caused by industrial pollution and climate change has threatened the survival of aquatic habitants. As a primary link between environmental changes and physiological responses, the role of neuroendocrine system in acid-base regulation under pH disturbance in fish remains unclear. Previous study indicated that Endothelin-1 (EDN1) was involved in regulation of skin acid secretion in zebrafish embryos. The aim of this study is to explore the role of EDN1 in acute regulation of acid secretion upon acidic challenge in fish. The results showed that skin acid secretion of zebrafish embryos was stimulated in 6hr after low pH (pH4) treatment, but no concomitant changes were observed on the expression of H+-ATPase (HA). Expression of EDN1was also increased in 4hr after treatment while the expression of other hormones increase at latter timepoints. Moreover, the expression of ionocyte differentiation factors increased in 12hr after treatment, implying the long-term regulatory mechanism to acidic stress may be turned on in a latter stage and the involvement of EDN1 in short-term regulation of acid secretion. During acclimation to moderate acid conditions (pH 5.5), expression of EDN1 was upregulated while no significant difference was observed in the transcription levels of H+-ATPase and ionocyte differentiation factor, implying that EDN1 may be involved in regulating moderate acid challenge.
|