Feeding Schedule Alteration of Daily Rhythm in Tyrosine Alpha-Ketoglutarate Transaminase of Rat Liver

Science  16 Feb 1968:
Vol. 159, Issue 3816, pp. 738
DOI: 10.1126/science.159.3816.738


Liver tyrosine alpha-ketoglutarate transaminase has a daily rhythm such that in rats fed on an unrestricted basis the activity is highest at approximately 11:00 p.m. In contrast, rats fed only from 8:00 a.m. to noon show a markedly different rhythm in the enzyme, with maximum activity at 11:00 a.m. Controlling the time of food intake seems to be a useful means of studying the mechanism of the daily changes in this enzyme.