干露及恢复过程中菲律宾蛤仔免疫指标的变化

在滩涂养殖和运输过程中,菲律宾蛤仔经常处于干露状态。笔者研究了蛤仔在干露胁迫和随后的恢复过程中酶活力和免疫相关物质含量的变化,初步揭示了滩涂贝类耐干露的生理学机制。在蛤仔干露12、24、48 h,以及恢复培养2、6、12、24 h时分别取蛤仔鳃和内脏团,测定酶活力及免疫相关物质含量,设持续海水养殖的蛤仔为对照组。结果表明,蛤仔在干露胁迫12 h和24 h时,内脏团AKP活力显著高于对照组(P<0.05);CAT活性在整个实验中与对照组差异不显著(P>0.05),鳃中AKP和CAT活力与对照组差异不大;内脏团SOD活力在干露12 h时显著升高,而鳃中SOD活力在恢复期显著升高(P<0.05);内脏团中MDA含量在干露24 h时显著高于对照组,鳃中MDA含量在干露12 h和24 h时显著低于对照组;内脏团NO含量在恢复海水后6 h时显著高于对照组(P<0.05),而鳃在干露48 h时NO含量显著高于对照组。分析认为,干露过程中,蛤仔呼吸代谢减慢,鳃的生理机能维持平稳或受到抑制,代谢和免疫保护作用主要由内脏团来完成。恢复培养时,随着呼吸作用和血液循环的恢复,鳃逐渐承担起部分抗氧化功能,使机体迅速恢复到正常生理状态。

The Effects of Air Exposure and Recovery on Immune Parameters of Ruditapes philippinarum

Manila clam (Ruditapes philippinarum) is often exposed in air during the cultivation and transportation. In order to detect the physiological features of clams suffered from air exposure, we studied the changes of enzyme activities and immunity substances during air exposure and recovery stages. The gills and visceral masses were sampled at 12 h, 24 h and 48 h after air exposure and at 2 h, 6 h, 12 h and 24 h after recovery in sea water. The enzyme vitalities and the important immune related substances were tested by the kits, and the clams cultured in sea water all along were considered as controls. The AKP activities of the visceral mass in air exposed clams for 12 h and 24 h were significantly higher than those in control (P<0.05). CAT activities in visceral mass were not different from those of controls. AKP and CAT values in gills were relatively stable during the whole experiment. SOD values were significant higher in visceral mass at 12 h of air exposure, and in gills during recovery for 2 h. MDA levels were significantly higher in visceral mass at 24 h of air exposure, and lower in gills during recovery for 12 h and 24 h than those in controls. NO showed the maximum value at 6 h after recovery in visceral mass and at 48 h of air exposure in gill. According to the results, it is concluded that the antioxidation and immunization are exercised mainly by visceral mass during air exposure. And during recovery process, along with the recovery of respiration and circulation, the gill exercises the antioxidation to some extent, and then the clams quickly return to the normal physiological level.