急性热应激对西伯利亚鲟肝功指标及肝脏热休克蛋白表达的影响

Effects of Acute Heat Stress on Hepatic Biochemical Index and Gene Expression of Heat Shock Proteins in Acipenser Baeri

【目的】探究急性热应激对西伯利亚鲟(Acipenser baeri)肝脏功能的影响。【方法】将(34.905±3.761)g西伯利亚鲟从23℃水体迅速移至30℃水体中,在热应激3、6、12、24、48和96 h检测血清谷丙转氨酶(ALT)、谷草转氨酶活力(AST)和总蛋白含量(TP),并利用实时荧光定量PCR法(qRT-PCR)检测肝脏hsp70和hsp90βmRNA的相对表达量。【结果】西伯利亚鲟血清谷丙转氨酶和谷草转氨酶活力均呈现先升高后降低的趋势,在高温胁迫48 h达到峰值。血清总蛋白和白蛋白含量整体维持恒定。肝脏hsp70和hsp90β的相对表达量均在热应激后迅速上升,在6 h达到峰值,96 h降至0时刻水平。【结论】急性热应激对西伯利亚鲟幼鱼的肝脏功能产生一定影响,但是在胁迫96 h后均恢复到正常水平;肝脏中热休克蛋白70和90均参与生理调节,以应对热应激对肝脏细胞的损伤。

【Objective】To evaluate the effects of acute heat stress on hepatic function of juvenile sturgeon.【Method】Acipenser baeri juveniles with body weight of(34.905±3.761) g in 23 ℃ water were transferred rapidly to 30 ℃ water. The ALT activities, AST activities and the total protein concen-tration in serum were measured at 3, 6, 12, 24, 48 and 96 h after heat stress. What’s more, the m RNA expressions of hsp70 and hsp90β in liver were measured by qRT-PCR.【Result】 The results showed that the activities of ALT and AST in serum reached maximum at 48 h after heat stress, and then decreased. However, the concentration of total protein and albumin remained stable.Expression levels of hsp70 and hsp90β m RNA in liver were up-regulated immediately after heat stress, and peaked at 6 h. And then, m RNA expression levels of hsp70 and hsp90β dropped to the normal level.【Conclusion】In conclusion, the hepatic function of sturgeon was influenced by the acute heat stress to acertain extend. hsp70 and hsp90β were involved in cell regulations to avoid the liver damage from heat stress.