Effects Of Acoustic Stress On Physiological And Biochemical Indexes And Hsp70 Expression Of Epinephelus Coioides

As one of the precious aquatic fish,Epinephelus coioides are deeply loved by consumers.Epinephelus coioides are one of the important economic fish which is cultured in the southern coastal areas of China,especially in Guangdong and Fujian province.Epinephelus coioides have great social and economic benefits and nutritional value,so ifs especially important to protect its growth environment.However,with the development of society,human activities such as maritime shipping,oil and gas exploration,and offshore wind farm construction have caused an increasing noise in marine environment,and underwater noise has has a certain impact on fishes Js behavior and physiology.Therefore,exploring the breadth and depth of noise impact,and using an effective method to reduce damage is an urgent problem that needs to be solved urgently.In this experiment,we investigate the noise situation in the wind farm(Xinliao island,Zhanjiang),and constructs a sine wave pure sound(600 Hz,130 dB re1?Pa)in the laboratory.A simulation experiment of acoustic stress was carried out on Epinephelus coioides,which is an specie of economic fish in coastal areas of China.To investigate the changes of the activities on non-specific immunity and anti-oxidation-related enzymes of Epinephelus coioides under a certain period of time.Therefore,we detect the pathological changes of liver and expression of Hsp70 by Western blot and immunohistochemistry.The effects of acoustic stress on Epinephelus coioides were evaluated physiologically and biochemically in order to provide a scientific reference for the acoustic protection of fishes.The main result as follows:1.The activity of ACP,AKP,GPT and GOT enzymes in serum under the stress of stress was detected by Epinephelus coioides to investigate the response of non-specific immune related enzymes to acoustic stress.When the Epinephelus coioides were exposed to noise,the overall performance of ACP and AKP enzyme activity in serum deereased first and then increased,then decreased,and finally gradually recovered to the original level.GPT and GOT enzymes showed a trend of increasing first and then decreasing.After 120 h,the activities of ACP,AKP,GPT and GOT enzymes approached the control group.It indicates that the acoustic stress has a stress response to the body of the fish,and the damage of the non-specific immune system can be self-regulated and recovered with time.2.The effects of acoustic stress on the antioxidant index of fish were investigated by measuring the changes of SOD,CAT activities and MDA concentration in the liver under acoustic stress with Epinephelus coioides.The results showed that the activity of SOD and CAT increased gradually with the prolongation of stress time in the early stage of acoustic stress,and the concentration of MDA decreased.Then the CAT enzyme activity did not change significantly,but the SOD enzyme activity and MDA concentration showed a wave?like decline.At 120 h,the MDA concentration in the liver of the fish was slightly higher than that of the control group.3.After the acoustic stress,the lipid content in the cytoplasm of hepatocytes was increasing,and the cells were mostly vacuolated.In the later stage of the experiment,the hepatic sinus gap increased,the liver plate disappeared,the nucleus shifted or even disappeared,and there were red blood cell aggregation in the 12 h,48 h,and 72 h groups.However,during the experimental period,no obvious pathological changes such as tissue hyperplasia,necrosis,inflammation and fibrosis were observed in the liver cells of each group.It indicates that the pressure generated by noise will cause certain damage to the liver tissue of Epinephelus coioides,but whether it will affect the normal physiological function of the liver,it is necessary to further prolong the test of sound stress time.4.Like other vertebrates,Epinephelus coioides showed a stress response after stimulation,and the expression of Hsp70 gradually increased.The results showed that the expression level of Hsp70 was higher than that before stress(0h)after acoustic stress,and the expression level of Hsp70 was significantly higher than that before stress at 12 h and 120h.The results of immunohistochemistry showed that the positive cells were punctate or focally distributed.At 48 h,Hsp70 in some hepatocytes was transferred to the nucleus,forming a brown-yellow aggregate.The results showed that the acoustic stress caused damage to the liver tissue cells.