糖尿病的诊断与治疗策略(内分泌科).ppt

* 各位老师都知道，口服降糖药大致可分为：磺脲类促胰岛素分泌剂、非磺脲类促胰岛素分泌剂、双胍类药物、胰岛素增敏剂和葡萄糖苷酶抑制剂五类，而诺和龙代表了新一类的口服降糖药---非磺脲类促胰岛素分泌剂。 * 我们可以看到，各种胰岛素其作用时间与达峰时间都有所不同。 Lepore M et al. Diabetes. 2000;49:2142-2148. 所谓肠促胰素效应是指,无论是口服还是静脉用葡萄糖，在血糖浓度升高的情况相同下, 口服葡萄糖后胰岛素浓度 (血清c肽浓度是胰岛素浓度的测量指标)远远高于静脉用葡萄糖后的胰岛素浓度 。这中间的差值就是肠促胰素效应. 肠促胰素效应说明在血糖升高的时候有其他因素与胰岛素共同发挥控制血糖的作用。这种因素就是肠促胰素. GLP-1由肠道的L细胞分泌，被DPP4分解，GLP-1可作用于身体多个器官： 对于大脑，作用于饱食中枢，抑制食欲，在动物实验中发现，GLP-1可促进学习能力和保护神经系统； 对于胃肠道，可延缓胃排空，减少食物的摄取，从而降低体重； 作用于心脏，发现具有保护心血管的效果； 对于肝脏，可减少糖异生，减少肝糖生成； 最关键的对于胰腺组织，呈葡萄糖依赖性的促进胰岛素分泌、促进胰岛素合成，并呈葡萄糖依赖性的减少胰高糖素分泌； * * PCP slide kit Post-Paris Draft 1 The Incretin Effect in Subjects Without and With Type 2 Diabetes In 1964, it was demonstrated that the insulin secretory response was greater when glucose was administered orally through the GI tract than when glucose was delivered via intravenous (IV) infusion. The term incretin effect was coined to describe this response involving the stimulatory effect of gut hormones known as incretins on pancreatic secretion.1,2 The incretin effect implies that nutrient ingestion causes the gut to release substances that enhance insulin secretion beyond the release caused by the rise in glucose secondary to absorption of digested nutrients.1 Studies in humans and animals have shown that the incretin hormones GLP-1 and GIP account for almost all of the incretin effect,3 stimulating insulin release when glucose levels are elevated.4,5 Although the incretin effect is detectable in both healthy subjects and those with diabetes, it is abnormal in those with diabetes, as demonstrated by the study shown on the slide.6 In this study, patients with type 2 diabetes and weight-matched metabolically healthy control subjects were given glucose either orally or IV to achieve an isoglycemic load.6 In those without diabetes (shown on the left), the plasma insulin response to an oral glucose load was far greater than the plasma insulin response to an IV glucose load (incretin effect)—that is, the pancreatic beta cells s