Minimal O₂Consumption as an Index of Thyroid Status: Standardization of Method

Minimal 02 consumption (MOC) in the rat was measured after ablation of the adrenals, gonads, pancreas, pineal, pituitary, thymus, thyroid and parathyroids. Only primary (thyroidectomy) or secondary (hypophysectomy) thyroid function ablation lowered the MOC. Various hormones were replaced alone or in certain combinations in intact or in operated rats: cortisone, corticosterone, desoxycorticosterone, estradiol, progesterone, testosterone, thyroxine (T4), triiodothyronine (T3), adrenocorticotrophic hormone (ACTH), growth hormone (GH), prolactin, vasopressin and oxytocin. Only T4, T3 increased the MOC. No hormone given with T4 altered the response to T4 given alone. GH doubled the body wt of young hypophysectomized rats but did not alter the MOC. (Endocrinology93: 61, 1973)