Factors affecting normal carbohydrate levels in Rana pipiens

Variation in Rana pipiens blood glucose levels caused by assay techniques was at least 50% of basal levels. Increases caused by handling and anesthesia were as great as 200% for glucose and 800% for lactate. Dietary status induced variations as great as 100% in blood glucose and muscle glycogen and 600% in liver glycogen. Maximal seasonal differences (March to August) of approximately 50% for blood glucose and tissue glycogen concentrations were observed. Frogs from different geographic areas showed differences in October glycogen reserves as great as 25 to 50%.