Abstract: | The activity of 3-hydroxybutyrate dehydrogenase (EC 1.1.1.30) in the isolated rat liver mitochondria changes but slightly during 24 h. In animals which were fed 10% ethanol solution for 3.5 months the enzyme activity varies within the daily cycle: maximum--at 10 p. m., minimum--at 1-4 p. m. and at 4-7 a. m.; the average daily activity gets three times lower. The cessation of the alcohol consumption makes average daily activity of the enzyme only two times higher, but the character of daily changes in the activity is different: the maximum is observed at 4-7 p. m., the minimum at 4-7 a. m. |