Acute Toxicity of Okadaic Acid to the Embryonic Development of Egg and Larvae of Sparus macrocephalus
大田软海绵酸对黑鲷胚胎发育及仔鱼的急性毒性

In order to study the acute toxicity of okadaic acid to the embryonic development of marine life as well as its biochemical mechanism, acute toxicity experiments were conducted on the eggs and larvae of Sparus macrocephalus using static and semi-static method. Results showed that both mortality and malformation of eggs significantly increased under the exposure of okadaic acid, while the hatchability rate was relatively less affected. The median lethal concentrations of larvae were 51.63, 45.58, 37.97 and 25.72 nmol L-1, respectively, after exposure of 24, 48, 72 and 96 hours to okadaic acid. A decrease in toxic accumulation in the bodies of the larvae was observed with the extension of exposure time. When exposed to okadaic acid, the activity of GSH-PX was induced significantly, while the activity of ACP was relatively less affected. Moreover, okadaic acid also affected the metabolism of nucleic acid and DNA synthesis in larval hepatocyte, which led to a significant change in the RNA/DNA ratio.