Characteristics of EST and α-AMY isozymesin fishes with different food structures

By means of poyacrylamid gel electrophoresis，two isozymes（EST，α-AMY）in liver，muscle，heart，eye，gill，kidney of six kinds of adult fish including Megalobrama terminalis，Hemiculter leucisculus，Cirrhina cuvier，Ctenopharyngodon idellus，Mylopharyngodon piceus，Siniperca chuatsi were studied. The results showed that the ESTand α-AMY isozymes were very complicated and all the isozyme phenotypes exhibited tissue-specificity. The species andexpression degree of EST isozyme was higher than that of α-AMY isozyme in these fishes. The activities of EST isozymeand α-AMY isozyme in liver and kidney were higher than those in other organs. There exited difference in differentfeeding fishes，so analysis on the characteristic of EST and α-AMY isozymes could reveal the current status of feedinghabitat，know the nutrition sources and ecological condition of fish habitats.