Lönnroth P
Department of Internal Medicine, Sahlgrenska Hospital, Göteborg, Sweden.
J Intern Med Suppl. 1991;735:23-9.
Insulin regulates cellular metabolic reactions by its action on the plasma membrane, intracellular enzymes and the nucleus. The first stage in the propagation of the insulin signal is the coupling of insulin to specific receptors at the cell surface. The exact mechanism whereby the transmembrane signalling mechanism (s) results in different insulin-mediated cellular effects is not known. However, the insulin receptor tyrosine kinase, the expression of second messengers, and the action of protein kinase C may, either individually or in combination, mediate some of the insulin effects, such as translocation and activation of glucose transporter proteins. Insulin resistance in clinical conditions such as insulin-dependent diabetes mellitus (IDDM), non-insulin-dependent diabetes mellitus (NIDDM), hypertension and obesity may be acquired to a large extent, and is thus partially reversible. Regulatory factors in insulin sensitivity, such as free fatty acids, counterregulatory hormones and blood glucose level, play an important role in the metabolic control and pathogenesis of insulin resistance in man.
胰岛素通过作用于质膜、细胞内酶和细胞核来调节细胞代谢反应。胰岛素信号传导的第一阶段是胰岛素与细胞表面的特定受体结合。跨膜信号传导机制导致不同胰岛素介导的细胞效应的确切机制尚不清楚。然而，胰岛素受体酪氨酸激酶、第二信使的表达以及蛋白激酶C的作用可能单独或共同介导一些胰岛素效应，如葡萄糖转运蛋白的易位和激活。在诸如胰岛素依赖型糖尿病（IDDM）、非胰岛素依赖型糖尿病（NIDDM）、高血压和肥胖等临床病症中，胰岛素抵抗在很大程度上可能是后天获得的，因此部分是可逆的。胰岛素敏感性的调节因子，如游离脂肪酸、对抗调节激素和血糖水平，在人体胰岛素抵抗的代谢控制和发病机制中起重要作用。
