Thyroxine-Induced Cardiac Hypertrophy and Adrenoceptor Changes
نویسنده
چکیده
Short-term (5 days) administration of L-thyroxine (0.1 mg/kg i.p. daily) to adult SpragueDawley rats induces a modest degree of cardiac hypertrophy (22% increase in heart weight/body weight ratios) and directionally opposite changes in cardiac adrenoceptors (24% increase in fi-adrenoceptors and 201% decline in ae-adrenoceptors). Pretreatment with colchicine did not affect the ability of L-thyroxine to induce cardiac hypertrophy but prevented its effects on both ffand ael-adrenoceptors. These results suggest a selective involvement of microtubules in the action of thyroid hormones on the expression of cardiac adrenoceptor genes. (Circulation Research 1991;68:309-313)
منابع مشابه
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تاریخ انتشار 2005