Garćia-Sáinz J A, Litosch I, Hoffman B B, Lefkowitz R J, Fain J N
Biochim Biophys Acta. 1981 Dec 18;678(3):334-41. doi: 10.1016/0304-4165(81)90112-4.
It has been suggested that part of the increased beta-catecholamine responsiveness in hyperthyroid animals is due to a decrease in alpha-catecholamine action. The present results indicate that neither hyperthyroidism nor hypothyroidism altered the alpha 2-adrenergic inhibition of adenylate cyclase or the alpha 1-adrenergic stimulation of phosphatidylinositol turnover in adipocytes from the white adipose tissue of hamsters. No effect of hyperthyroidism was found on the Kd for binding of [3H]dihydroergocryptine or the number of binding sites in membranes prepared from hamster adipocyte tissue. The stimulation of cyclic AMP due to beta-catecholamines was enhanced in adipocytes from hyperthyroid hamsters, as was lipolysis. However, in adipocytes from hyperthyroid hamsters the maximal stimulation of cyclic AMP due to isoproterenol, ACTH or epinephrine plus yohimbine, as seen in the presence of adenosine deaminase and theophylline, was less than in adipocytes from euthyroid hamsters. The activation of adenylate cyclase by isoproterenol was the same in membranes from hyperthyroid as compared to those from euthyroid hamsters in the absence or presence of guanine nucleotides. These data suggest that thyroid status has little effect on alpha-catecholamine action by enhances the activation of lipolysis by beta-catecholamine agonists.
有人提出，甲状腺功能亢进动物体内β - 儿茶酚胺反应性增加的部分原因是α - 儿茶酚胺作用减弱。目前的结果表明，甲状腺功能亢进和甲状腺功能减退均未改变仓鼠白色脂肪组织脂肪细胞中腺苷酸环化酶的α2 - 肾上腺素能抑制作用或磷脂酰肌醇周转率的α1 - 肾上腺素能刺激作用。未发现甲状腺功能亢进对仓鼠脂肪细胞组织制备的膜中[3H]二氢麦角隐亭结合的解离常数（Kd）或结合位点数量有影响。甲状腺功能亢进仓鼠的脂肪细胞中，β - 儿茶酚胺引起的环磷酸腺苷（cAMP）刺激以及脂解作用均增强。然而，在腺苷脱氨酶和茶碱存在的情况下，甲状腺功能亢进仓鼠的脂肪细胞中，异丙肾上腺素、促肾上腺皮质激素（ACTH）或肾上腺素加育亨宾引起的cAMP最大刺激作用小于甲状腺功能正常仓鼠的脂肪细胞。在有无鸟嘌呤核苷酸的情况下，甲状腺功能亢进仓鼠的膜中异丙肾上腺素对腺苷酸环化酶的激活作用与甲状腺功能正常仓鼠的膜相同。这些数据表明，甲状腺状态对α - 儿茶酚胺作用影响很小，但会增强β - 儿茶酚胺激动剂对脂解的激活作用。
