Abstract
We determined the annual change in the intermediary metabolism of glucose through the variations of specific activity of fructose 1,6-bisphosphatase (FBPase), alanine aminotransferase (AAT) and pyruvate kinase (PK). Fish (average mass 330 g) were kept in cages under natural conditions of temperature and photoperiod and fed with a commercial diet. FBPase, AAT and PK increased their activity in June in different ways: AAT and PK increased V max, and FBPase increased the velocity at subsaturating substrate concentrations, changing K m. The reproduction period modified the annual tendency of changes in the enzyme activities in both parameters, K m and V max, except for K m of PK which shows a circa-annual rhythm. No relation between the changes of enzymes activity and photoperiod or temperature has been found in this study, except for K m of AAT which presents a positive correlation with photoperiod and a negative correlation with temperature.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have