Lenzen S, Kücking H
Acta Endocrinol (Copenh). 1982 Aug;100(4):527-33. doi: 10.1530/acta.0.1000527.
Both L-thyroxine and D-thyroxine induced an inhibition of glucose-induced insulin secretion with comparable time- and dose-dependent characteristics. L-thyroxine was ten times more potent than D-thyroxine. While L-thyroxine and a ten times higher dose of D-thyroxine had a similar potency in inducing hyperthermia and hypocholesterolaemia, hyperglycaemia in response to D-thyroxine was less pronounced than in response to L-thyroxine. This difference may be explained by a greater depletion of liver glycogen stores and consequently more limited capacity for provision of glucose for the circulation. The results support the view that the differences between L-thyroxine and D-thyroxine are quantitative. Adrenergic contribution to L-thyroxine- and D-thyroxine-induced inhibition of insulin secretion by rat pancreas is apparently of minor importance. Treatment of the rats with propranolol as well as with reserpine or 6-hydroxydopamine did not alleviate L-thyroxine- or D-thyroxine-induced inhibition of insulin secretion by rat pancreas.
L-甲状腺素和D-甲状腺素均可抑制葡萄糖诱导的胰岛素分泌，且具有相似的时间和剂量依赖性特征。L-甲状腺素的效力是D-甲状腺素的10倍。虽然L-甲状腺素和剂量高10倍的D-甲状腺素在诱导体温过高和低胆固醇血症方面具有相似的效力，但D-甲状腺素引起的高血糖症不如L-甲状腺素明显。这种差异可能是由于肝糖原储备消耗更大，因此为循环系统提供葡萄糖的能力更有限。这些结果支持L-甲状腺素和D-甲状腺素之间的差异是定量的这一观点。肾上腺素能对大鼠胰腺中L-甲状腺素和D-甲状腺素诱导的胰岛素分泌抑制作用显然不太重要。用普萘洛尔以及利血平或6-羟基多巴胺处理大鼠并没有减轻L-甲状腺素或D-甲状腺素对大鼠胰腺胰岛素分泌的抑制作用。
