THE EFFECT OF ADRENALECTOMY AND OF FASTING ON THE FUNCTIONAL CAPACITY OF THE RAT'S GASTROCNEMIUS

Abstract

Optical records were obtained of isometric contractions of the gastrocnemius muscles of normal, adrenalectomized, and fasting rats. Induction shocks at the rate of 60 a sec. were used as stimuli, and the response was continuously recorded from the beginning of stimulation until fatigue. The maximum tension exerted at the beginning of the response was the same for all the groups of animals, and the muscles from the adrenalectomized rats fatigued only a little more quickly than the others. The total performance of the adrenalectomized animals was distinctly inferior to the others, because the tension declines more rapidly during the early part of the period of stimulation. The performance of muscles from fasting animals is not inferior to that of the controls; therefore, the functional deficiency observed after adrenalectomy is not due to the general inanition of the organism which accompanies adrenal insufficiency.