Petrides A S
Klinik für Allgemeine Innere Medizin und Gastroenterologie, Augusta-Kranken-Anstalt, Bochum.
Z Gastroenterol. 1999 Jun;Suppl 1:15-21.
About 80% of patients with chronic liver diseases such as cirrhosis are glucose intolerant and some 20-30% eventually develop frank diabetes mellitus. In a given individual it seems impossible to determine whether or not acquired liver diabetes or inherited non-insulin-dependent diabetes mellitus is present. The high prevalence, however, of impaired glucose tolerance and the finding that insulin sensitivity is reduced in nearly all cirrhotic patients before any impairment in glucose tolerance becomes manifest, make it likely that in the majority of patients the hepatic disease is the cause of the development of the hepatogenous diabetes. The insulin resistance resides in muscle and largely results from a defect in glycogen synthesis. Glucose intolerance ensues as a result of two abnormalities that occur simultaneously: insulin resistance of muscle and an inadequate response of the B-cell to appropriately secrete insulin to overcome the defect in insulin action. Diabetes mellitus in insulin-resistant cirrhotic patients develops as a result of a progressive impairment in insulin secretion together with the development of hepatic insulin resistance, leading to fasting hyperglycemia. Until recently, only little was known about the etiology of insulin resistance and impaired insulin secretion. However, most recent studies have shown that prolonged reduction of hyperinsulinemia in cirrhosis normalize insulin-mediated glucose uptake and glycogen synthesis in muscle. These results indicate that chronic hyperinsulinemia causes insulin resistance in cirrhosis and therefore plays a central role in the etiology of the hepatogenous diabetes.
约80%的肝硬化等慢性肝病患者存在葡萄糖不耐受,约20%-30%最终会发展为显性糖尿病。对于特定个体而言,似乎无法确定其患有的是获得性肝源性糖尿病还是遗传性非胰岛素依赖型糖尿病。然而,葡萄糖耐量受损的高患病率以及几乎所有肝硬化患者在葡萄糖耐量出现任何损害之前胰岛素敏感性就已降低这一发现,表明在大多数患者中,肝脏疾病是肝源性糖尿病发生的原因。胰岛素抵抗存在于肌肉中,主要是由糖原合成缺陷导致的。葡萄糖不耐受是由于同时出现的两种异常情况所致:肌肉的胰岛素抵抗以及胰岛B细胞对适当分泌胰岛素以克服胰岛素作用缺陷的反应不足。胰岛素抵抗的肝硬化患者发生糖尿病是由于胰岛素分泌逐渐受损以及肝脏胰岛素抵抗的发展,导致空腹血糖升高。直到最近,人们对胰岛素抵抗和胰岛素分泌受损的病因了解甚少。然而,最新研究表明,肝硬化患者高胰岛素血症的持续降低可使胰岛素介导的肌肉葡萄糖摄取和糖原合成恢复正常。这些结果表明,慢性高胰岛素血症在肝硬化中导致胰岛素抵抗,因此在肝源性糖尿病的病因中起核心作用。