盐度突变对凡纳滨对虾组织碳酸酐酶活性的影响

Effects of abrupt salinity changes on the carbonic anhydrase activity in the tissues of Litopenaeus vannamei

采用改进的△pH法榆测凡纳滨对虾组织碳酸酐酶活性，监测了环境盐度从5突变到25后对虾鳃和触角腺组织碳酸酐酶活性及其血淋巴渗透浓度的动态变化。结果表明：（1）鳃组织碳酸酐酶活性在盐度突变后4d内没有显著变化，活性水平在（21．68±1．25）μmol CO2/（mg·min），第5～11天有显著性的增高现象，在第10天活性最高，为（43．03±2．82）μmol CO2／（mg·min），第12天回落至起始水平；（2）触角腺碳酸酐酶活性动态变化的模式与鳃相似。起始增高时间比鳃晚6d；（3）触角腺碳酸酐酶活性显著增高起始的时间与鳃组织碳酸酐酶活性开始显著下降的时间有关联性；（4）在低盐度时，凡纳滨对虾属于强高渗调变生物。

The effects of abrupt salinity changes （salinity of 5 - 25） on the carbonic anhydrase （CA） activity in the pooled gills and antennal gland and hemolymph osmotic concentration of Litopenaeus vannamei were investigated in this paper, and the carbonic anhydrase activity was measured by the means of improved delta pH method. The results showed that （ 1 ） the CA activity of the pooled gills didn＇ t change significantly in 4 days after abrupt salinity changes, with the activity level of （21.68 ± 1.25） μaol CO2/（mg·min）. CA activity increased from days 5- 11 after abrupt salinity changes, and the peak activity of （43.03 ± 2.82） μmol CO2/（mg· min） appeared on day 10, and the activity reduced to the same level as the beginning of experiment on and after day 12. （2） the CA activity changes in antennal gland were similar to those in the pooled gills; however, the time that the CA activity of antennal gland began to increase was 6 days later than that of pooled gills. （3） the beginning time of CA activity increase of antennal gland was related to the time of CA activity decrease of pooled gills. （4） Litopenaeus vannamei was a strong hyper-osmoregulator when salinity was low.