Metabolic changes in the intact rat and excised tissues after thyroidectomy

¹ Department of Physiology, Marquette University School of Medicine, Milwaukee, Wisconsin

The oxygen consumption of the intact rat and selected excised tissues was determined for 28 days following surgical thyroidectomy. By the 3rd day, the whole-animal basal metabolism showed a reduction to 90% of the normal value followed by a continuous fall to the basal level of 71% on the 7th day. In general, the excised tissues followed a similar pattern to that of the thyroidectomized intact animal. Heart, psoas and liver nearly paralleled the changes found in the whole animal, having correlation coefficients of 0.93, 0.93 and 0.97, respectively. Diaphragm (r = 0.84) decreased sharply to 73% by day 3 then less rapidly to 42% on the final day of the study. Kidney (r = 0.75) showed no decrease until day 2 then fell to a minimal value of 82% on day 20. Brain (r = 0.77) declined only 16% reaching the basal level of 84% of normal 24 days after thyroidectomy.