@article{oai:ir.kagoshima-u.ac.jp:00010783, author = {SAMESHIMA, Muneo and MAZID, Md. Abdul and HORINOUCHI, Yoshiki}, journal = {鹿児島大学水産学部紀要=Memoirs of Faculty of Fisheries Kagoshima University}, month = {2016-10-31}, note = {The changes in aspartate aminotransferase activities in heart, liver, brain, intestine and spleen of Tilapia nilotica with various environmental conditions have been examined. The heart shows the highest activity in these organs. The organs of T.nilotica show higher activity of aspartate aminotransferase in summer and lower in winter. The activity is directly related to the temperature of the cultural water. The sample fishes have been transferred from fresh water to sea water, and the effect on their aspartate aminotransferase activity have been studied. The activity increases while the first few days after releasing the fishes into sea water due to the physiological upset, which occurs in their body, but the following days, the activity does not change significantly. A reason for which the fishes could endure the sea water-culture is explained as follows; the fishes have been cultured in a pond having 3.6-6.4% salinity for several years, and have got a tolerance to drastic change on osmotic pressure. The inhibitory action of divalent metal ions on aspartate aminotransferase have been tested, Ba^<2+> and Hg^<2+> show high inhibition on the enzyme activity. Partially, purification have been studied with the liver-enzyme and the activity becomes three times stronger than the crude enzyme.}, pages = {301--312}, title = {Aspartate Aminotransferase Activities in Various Tissues of Tilapia nilotica}, volume = {29}, year = {} }