THE INFLUENCE OF THYROIDECTOMY ON THE VARIABILITY OF NEUROMUSCULAR ACTIVITY IN THE RAT

Abstract

Inj. of thyroxin into normal albino rats resulted in a decreased level of neuromuscular activity as measured by the revolving drum technique. This decreased activity may function as a homeostatic mechanism in that it tends to restore normal physiologic equilibrium. Thyroidectomy resulted in a decreased level of activity and a decrease in day-to-day variability of activity probably as a result of lowered nervous irritability, or of the removal of a factor with a variable influence. There is less inter-individual variation in the hvpothyroid than in the normal state.