수온노출에 따른 각시붕어, Rhodeus uyekii의 HSP70 family gene과 혈장 내 glucose 변화

Abstract

Temperature is one of common variables in the aquatic environment that directly affect survival of aquatic organisms. Temperature also changes the physiological functions associated with the stress response of fish. Heat shock protein and glucose levels in plasma can be used as general stress indicators in fish. The objective of the present study was to investigate the expression of heat shock protein 70 family mRNAs as cellular stress responses and the levels of plasma glucose in Korean rose bitterling, Rhodeus uyekii exposed to water temperature. The experimental fish (TL; 4.0±0.5cm, BW; 0.75±0.3g) were divided into 4 groups that were exposed at 20, 24, 28 and 32℃, respectively. The expression of RuHSP70 family mRNA and the levels of plasma glucose were investigated. RuHSP70 family mRNA was expressed highly in the hepatopancreas, testis and ovary of normal R. uyekii. Quantitative real-time PCR analysis showed the expression of RuHSP70 family mRNA was elevated by higher water temperature (32℃) in primary hepatopancreatic cells of R. uyekii. The plasma glucose level was the highest in R. uyekii exposed to higher water temperature (28℃). In addition, histological observation of gill tissue in R. uyekii, gill lamella was damaged or curved at the higher temperature. These results showed that the expression of RuHSP70 family mRNA as well as the change of plasma glucose level in R. uyekii are influenced by the high water temperature.