热应激对大正三色锦鲤非特异性免疫指标及HSP70基因表达的影响

摘要

为探讨锦鲤的抗逆机理,在实验室条件下研究了持续热应激对大正三色锦鲤非特异性免疫指标及HSP70基因相对表达量的影响.分别于应激前、应激后2、6、10、14、18、22、26 h进行取样测定呼吸爆发、补体蛋白3(C3)、超氧化物歧化酶(SOD)、丙二醛(MDA)以及热休克蛋白70 (HSP70)基因的相对表达量.结果发现,热应激后呼吸爆发降低,在应激后2、10、18～26 h降低显著(P＜0.05)；热应激2h后血清中C3含量略有上升,应激6～26 h过程中与应激前相比均下降,应激14 ～ 22 h显著地下降(P＜0.05)；热应激下血清中SOD有上升的趋势,但差异不显著(P＞0.05)；热应激下,血清中MDA浓度升高,应激10～18 h上升显著(P＜0.05)；应激后2、26 hHSP70基因的相对表达量与应激前相比显著性地上升了5.93倍、2倍(P＜0.05),应激后6～22 hHSP70基因的相对表达量与应激前水平无显著性差异(P＞0.05).结果表明,热应激影响锦鲤非特性免疫指标,降低锦鲤非特异性免疫力；HSP70的表达受热应激调节,热应激下诱导合成的HSP70对锦鲤起到一定的应激保护作用.%In order to explore the mechanism of koi' s anti-stress, the study was performed to examine the effect of continuous heat stress on non-specific immune parameters and HSP70 gene expression in Taisho Sanke koi under the laboratory conditions. Samples for detections of respiratory burst,complement protein 3 (C3) ,superoxide dismutase(SOD), malondialdehyde (MDA) and relative expression content of heat shock protein 70(HSP70) were taken before stress ,2,6,10,14,18,22 and 26 h after stress,respectively. The results were as follows. Respiratory burst activity decreased after stress, and it decreased significantly after stress 2, 10,18-26 h(P<0. 05). The content of serum C3 was increased slightly 2 h after stress. Compared to before stress,the level of serum C3 decreased 6 -26 h after stress,and it decreased significantly 14-22 h after stress(/'<0.05). The level of serum SOD had the trend of augment,but not significantly(P>0.05). The concentration of serum MDA increased after stress, and it increased significantly after stress 10 -18 h (P < 0.05). Compared to before stress, the relative expression content of HSP70 gene significantly increased by 5.93 times 2 h after stress and 2 times 26 h after stress(P <0. 05). 6 -22 h after stress,the relative expression content of HSP70 gene had no significant difference from that before stress (P >0. 05). These results indicated that heat stress affected non-specific immune parameters, and lowered non-specific immunity of Taisho Sanke koi. The expression of HSP70 gene was regulated by heat stress. HSP70 induced by heat stress played a role of stress protection to koi.