Blood Sugar Level and Activity in Rats.

Abstract

The primary problem in the study of activity is to discover those internal factors and conditions which stimulate an animal to become active. Since the energy for muscular contraction comes from the oxidation of glucose it is conceivable that a relation exists between blood sugar and activity.

In studying this relationship 45 male albino rats, 5 months old, were used; these were divided into 2 groups of 19 and 26 animals respectively. Their activity was recorded in revolving drums of the type used by Slonaker, Hoskins, and others who have worked on activity. The animals lived in these cages for six weeks; they were fed 30 cc. of bread and milk at a regular hour each day, and daily turns of each cage recorded. Temperature and light conditions were constant. The animals received no food during the 24 hours just preceding blood sugar but they remained in the activity cages until about 2 hours before their death. The activity measure which was chosen as best representing the level of an animal's activity at the time blood sugars were done, was the median of his last five days runs.

The animal was sacrificed for making the blood sugar analysis. The sugar determinations were made according to Folin's copper reduction method as revised in his 1926 articles. Sugars varied within a range 66 to 125 mg. per 100 cc. The average for all animals was 95 mg.

Correlations between blood sugar and activity ran thus: