Changes of Aspartic Acid in Various Cerebral Structures of Hibernating and Aroused Ground Squirrels

Abstract

The concentrations of aspartic acid in various regions of the brain of European ground squirrels (Cilellus citellus), sacrificed at different stages of the hibernating cycle, have been estimated by means of two dimensional paper chromatography. On the basis of experimental results obtained the following conclusions have been derived:

1. Similar concentrations of aspartic acid where found in different cortical and subcortical areas of the ground squirrel brain.

2. In hibernation at rectal temperatures of 5° C, an important decrease of aspartic acid was found in all the regions studied.

3. Inversely, arousal from hibernation was associated with an increase of aspartic acid levels, atteining at 35° C the control values in a majority of investigated regions.

The possible explanations and significance of the results obtained have been briefly discussed.