Effects of glucose on glycogen synthetase, phosphorylase, and glycogen deposition in the perfused rat liver.
An increase in the perfusate glucose concentration from near zero to about 11 mM increased glycogen synthesis in the perfused, isolated rat liver from zero to a value about half the maximum seen in the intact animal. Increased synthesis appeard to due not only to provision of substrate but also to conversion of glycogen synthetase to the active form and of glycogen phosphorylase to the inactive form. These glucose effects, which are apparently independent of changes in levels of hormones or adenosine 3':5'-cyclic phosphate, may be physiologically significant for control of the blood glucose level.
A recurring problem in forensic medicine is the need to fix the time of death within the limits of probability. Errors in overestimating and underestimating the post-mortem interval based on body cooling is common. Post-mortem biochemistry has become a potent additional procedure in forensic death investigation. However, in our experiment, to determine the post-mortem interval we investigated the ATPase activity. The investigation was performed on the liver tissue of 25 corpses (21 men and four women) of age ranging between 40–60 years. The study of ATPase enzymatic activity shows that there is a considerable drop in the levels of ATPase activity with increasing post-mortem interval up to 24 h and this is one of the most reliable methods for estimating time of death.