Lang V, Vaugelade P, Bernard F, Darcy-Vrillon B, Alamowitch C, Slama G, Duée P H, Bornet F R
Institut National de la Recherche Agronomique, Jouy-en-Josas, France.
Am J Clin Nutr. 1999 Jun;69(6):1174-82. doi: 10.1093/ajcn/69.6.1174.
Precise knowledge of the rate of glucose absorption after meal feeding requires invasive methods in humans.
This study aimed to validate in an animal model a technique combining the euglycemic hyperinsulinemic clamp and oral carbohydrate loading (OC-Clamp) as a noninvasive procedure to quantify the posthepatic appearance of glucose after oral carbohydrate loading.
Twenty-one pigs were fitted with arterial, jugular, portal, and duodenal catheters and a portal blood flow probe. At glucose clamp steady state, duodenal glucose (0.9 g/kg; DG-Clamp) and oral carbohydrate (140 g corn or mung bean starch as part of a mixed meal; OC-Clamp) were administered while the glucose infusion was progressively reduced to compensate for the incremental posthepatic appearance of glucose. [3-3H]glucose was used to assess the glucose turnover rate.
Hepatic glucose production was totally suppressed by insulin infusion, and the whole-body glucose turnover rate remained stable during glucose absorption. The incremental portal appearance of glucose after the DG load was not altered by hyperinsulinemia, and the cumulative posthepatic appearance of glucose was 63 +/- 3% (x +/- SEM) of the DG load. The net hepatic portal appearance of glucose remained constant during absorption (34 +/- 3% of the load). After the OC load, the respective portal appearance rates of glucose were significantly different between carbohydrate sources; however, the rates paralleled those of the posthepatic appearance of glucose. Again, net hepatic glucose uptake expressed as portal appearance was similar for both carbohydrates.
The results validate the OC-Clamp method to monitor the posthepatic appearance of glucose after carbohydrate ingestion and to discriminate between different carbohydrate sources. The results suggest that the technique be used in humans.
精确了解餐后葡萄糖吸收速率需要在人体中采用侵入性方法。
本研究旨在在动物模型中验证一种将正常血糖高胰岛素钳夹技术与口服碳水化合物负荷（OC - 钳夹）相结合的技术，作为一种非侵入性程序，用于量化口服碳水化合物负荷后肝后葡萄糖的出现情况。
21头猪安装了动脉、颈静脉、门静脉和十二指肠导管以及门静脉血流探头。在葡萄糖钳夹稳态时，给予十二指肠葡萄糖（0.9 g/kg；DG - 钳夹）和口服碳水化合物（140 g玉米或绿豆淀粉作为混合餐的一部分；OC - 钳夹），同时逐渐减少葡萄糖输注以补偿肝后葡萄糖出现量的增加。使用[3 - 3H]葡萄糖评估葡萄糖周转率。
胰岛素输注完全抑制了肝葡萄糖生成，并且在葡萄糖吸收过程中全身葡萄糖周转率保持稳定。高胰岛素血症并未改变DG负荷后门静脉葡萄糖出现量的增加，肝后葡萄糖出现量的累积值为DG负荷的63±3%（x±SEM）。葡萄糖吸收过程中门静脉葡萄糖的净肝出现量保持恒定（负荷的34±3%）。OC负荷后，不同碳水化合物来源的门静脉葡萄糖出现率存在显著差异；然而，这些速率与肝后葡萄糖出现率平行。同样，两种碳水化合物以门静脉出现量表示的净肝葡萄糖摄取相似。
结果验证了OC - 钳夹方法可用于监测碳水化合物摄入后肝后葡萄糖的出现情况，并区分不同的碳水化合物来源。结果表明该技术可用于人体。
