Antioxidation and ATPase activity in the gill of mud crab Scylla serrata under cold stress

Mud crab (Scylla serrata) is an important commercial crustacean in China. An experiment was designed to study the effect of cold stress on S. serrata. After a one-week adaptation at 28oC, the temperature is suddenly reduced to 4oC. The crabs were sampled every 2 h for 10 h and dissected immediately to measure the enzyme activity. The crabs at room temperature (28oC) were used as the control group. The activity of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX), the content of malondialdehyde (MDA) and the activity of 4 ATPases (Na , K -ATPase; Mg2 -ATPase; Ca2 -ATPase; Ca2 , Mg2 -ATPase) were measured biochemically. In contrast to the control group, the SOD activity increased significantly from 2 to 6 h after the cold stress, and then decreased. The CAT and GPX activities increased in 2 h, and then decreased gradually. The content of MDA increased gradually in 4 h. The activity of Na , K -ATPase decreased in 2 h, increased up to the top value at Hour 6, then decreased again. The activities of Mg2 -ATPase, Ca2 -ATPase and Ca2 , Mg2 -ATPase increased significantly in 6 h, insignificantly in any other hours. Under cold stress, the activity of antioxidative enzymes in S. serrata was reduced at first then stabilized, ROS-scavenging weakened, and MDA accumulated gradually in the gill after 6 h. The activity of the 4 ATPases in the crab decreased after 6 h, suggesting that the ability to regulate ion concentration has been paralyzed. Therefore, the maximum period to sustain healthy meat in the crab under cold stress is 6 hours.     

波纹龙虾胚胎的离体培养及发育观察

对波纹龙虾不同发育时期的胚胎进行离体培养和显微观察。结果表明,初始培育的离体胚胎愈接近孵化期,其孵化率愈高(最高达80.0%);波纹龙虾胚胎发育经历受精卵、卵裂期、囊胚期、原肠期、中眼色素形成期、复眼色素形成期、心跳期、破膜前期和出膜期;胚胎在发育过程中颜色变化:橙红→深橙红→砖红→灰白→接近透明。     

A STUDY ON THE FORECAST AND REGULATION OF COORDINATED DEVELOPMENT OF URBAN ENVIRONMENT AND ECONOMY IN GUANGZHOU

ＡＳＴＵＤＹＯＮＴＨＥＦＯＲＥＣＡＳＴＡＮＤＲＥＧＵＬＡＴＩＯＮＯＦＣＯＯＲＤＩＮＡＴＥＤＤＥＶＥＬＯＰＭＥＮＴＯＦＵＲＢＡＮＥＮＶＩＲＯＮＭＥＮＴＡＮＤＥＣＯＮＯＭＹＩＮＧＵＡＮＧＺＨＯＵＹａｎｇＳｈｉｈｏｎｇ（杨士弘）（ＤｅｐａｒｔｍｅｎｔｏｆＧ...