The pattern of glycogen withdrawal within the liver acinus during fasting

Intraacinar regionality in glycogen withdrawal during fasting was studied in the liver of the mouse. When animals were fasted from 10.00 a.m. onwards, glycogen withdrawal began in zone 1, spreading gradually to zone 3, and after 12 h glycogen disappeared throughout the acinus. After 24 h new glycogen accumulated in various portions of the acinus. However, when animals were fasted from 10.00 p.m. or 12 midnight to the following morning, glycogen was withdrawn evenly throughout the lobule. After 24 h glycogen disappeared throughout the acinus. These results show that there is a heterogeneity in the hepatocyte with respect to glycogen withdrawal during fasting by day but not by night. Therefore, the discrepancy in reported results on the intraacinar distribution of glycogen during fasting is probably due to the time of sacrificing animals.