Oda Y, Tajima K, Mori-Tanaka M, Matsui I, Kitajima K, Miyagawa J, Hanafusa T, Mashita K, Tarui S
Second Department of Internal Medicine, Osaka University Medical School, Japan.
J Endocrinol Invest. 1991 Nov;14(10):867-73. doi: 10.1007/BF03347947.
The effect of methoxamine, a specific alpha 1-adrenergic agonist, on the release of T3, T4 and cAMP from perifused mouse thyroid was studied to clarify the role of the alpha 1-adrenergic receptor in the regulation of thyroid hormone secretion. TSH-stimulated T3 and T4 release was inhibited significantly by methoxamine. With regard to cAMP release, methoxamine inhibited TSH-stimulated cAMP release in the presence of 4-(3-butoxy-4-methoxybenzyl)-2-imidazolidinone but did not inhibit TSH-stimulated cAMP release in the presence of 3-isobutyl-1-methylxanthine. Methoxamine did significantly suppress TSH-stimulated release of T3 and T4 in the presence of each phosphodiesterase inhibitor. Depletion of Ca2+ in the perifusion buffer abolished completely the inhibitory effect of methoxamine on TSH-stimulated T3 and T4 release. The present study suggests that activation of the alpha 1-adrenergic receptor inhibits TSH-stimulated T3 and T4 secretion through a Ca(2+)-dependent mechanism in the mouse thyroid gland.
为阐明α1-肾上腺素能受体在甲状腺激素分泌调节中的作用，研究了特异性α1-肾上腺素能激动剂甲氧明对灌注小鼠甲状腺释放T3、T4和环磷酸腺苷（cAMP）的影响。甲氧明显著抑制促甲状腺激素（TSH）刺激的T3和T4释放。关于cAMP释放，在存在4-(3-丁氧基-4-甲氧基苄基)-2-咪唑烷酮的情况下，甲氧明抑制TSH刺激的cAMP释放，但在存在3-异丁基-1-甲基黄嘌呤的情况下，不抑制TSH刺激的cAMP释放。在每种磷酸二酯酶抑制剂存在的情况下，甲氧明确实显著抑制TSH刺激的T3和T4释放。灌注缓冲液中Ca2+的耗尽完全消除了甲氧明对TSH刺激的T3和T4释放的抑制作用。本研究表明，α1-肾上腺素能受体的激活通过小鼠甲状腺中依赖Ca(2+)的机制抑制TSH刺激的T3和T4分泌。
