thiouracil and Hyperinsulinism

Both clinical diabetes and chemically-induced diabetes have been reported to alter control processes of the hypothalamic-pituitary-thyroid axis. One of the sites of alteration appears to be depression of thyrotrophin releasing hormone (TRH) stimulated thyrotrophin (TSH) release. The present study examined the influence of sequential administration of streptozotocin and the goitrogen thiouracil to male mice for 4 weeks in view of their possibly opposing effects on TSH release. The drugs produced the expected results when administered singly, with streptozotocin producing hyperglycemia and thiouracil causing hypothyroxinemia and goitrogenesis. Additionally, thiouracil administration produced hyperinsulinemia. Sequential administration of the drugs appeared to ameliorate the thyroid status and glycemic condition caused by individual exposure. Streptozotocin reduced the goitrogenic influence of thiouracil and thiouracil reduced the hyperglycemia of streptozotocin, but not to control levels. Thus, sequential administration resulted in mice with simultaneously elevated circulating glucose and insulin levels, and depressed thyroxine levels. Similar effects on glucose, insulin, and the thyroxine levels have been reported clinically in patients with non-insulin-dependent diabetes mellitus.

Topics: Animals; Diabetes Mellitus, Experimental; Hyperinsulinism; Hypothalamo-Hypophyseal System; Hypothyroidism; Male; Mice; Streptozocin; Thiouracil; Thyroid Gland; Thyrotropin; Thyrotropin-Releasing Hormone