THE RELATIONSHIP OF THE ADRENAL AND THYROID GLANDS TO EXCISED MUSCLE METABOLISM

Abstract

The respiratory metabolism of the excised abdominal muscle of mice was determined by the Warburg differential method under the following experimental conditions: bilateral adrenalectomy; bilateral thyro-parathyroidectomy; adrenalectomy preceded by thyro-parathyroidectomy; adrenalectomy followed by experimental hyperthyroidism. A comparison was also made between the respiratory metabolism of the whole mouse and its excised muscle as affected by adrenalectomy. Aerobic metabolism of the excised muscle of the mice was increased during the 40 to 70 day period after adrenalectomy, but not when adrenalectomy was preceded by thyro-parathyroidectomy. During the same period adrenalectomized mice showed an increased susceptibility to thyroxin administration. During the same period the total respiratory metabolism and the excised muscle metabolism showed corresponding increases. It was concluded that the increased metabolism of mice following adrenalectomy was due to increased activity of the thyroids, and that the increased thyroid activity was probably in the nature of a compensation for adrenal insufficiency.