Moran T H, McHugh P R
Am J Physiol. 1981 Jul;241(1):R25-30. doi: 10.1152/ajpregu.1981.241.1.R25.
We have studied in Macaca mulatta both the gastric emptying of glucose, D-xylose, and fructose and the effects of these sugars on feeding. Glucose and D-xylose empty in the same fashion, i.e., linearly and more slowly with increasing concentration so that the delivery of solute to the small intestine is constant at 0.1 g/min over time and across concentrations. Fructose empties exponentially and more rapidly than the other sugars. When solutions of each of these sugars (37.5 g in 150 ml) preceded the monkey's daily 4-h feeding period there was a similar total reduction in food intake for each. However, fructose inhibited food intake in the first 2 h of feeding less than did the other sugars just as it inhibited gastric emptying less. D-Xylose, although mimicking glucose in both gastric emptying and feeding on the experimental day, produced, as it is poorly metabolized, a caloric deficit replaced by overeating on the subsequent control day. We conclude from the similarities between glucose and xylose that the stomach, while emptying nutrients, influences feeding and can be at least one source of signals for preabsorptive satiety and caloric homeostasis. The results with fructose require that other sites must be active to permit a similar regulation of feeding to occur despite differing gastric emptying characteristics.
我们在恒河猴身上研究了葡萄糖、D-木糖和果糖的胃排空情况以及这些糖类对进食的影响。葡萄糖和D-木糖以相同的方式排空，即呈线性排空，且随着浓度增加排空速度减慢，这样溶质向小肠的输送在不同时间和浓度下均恒定为0.1克/分钟。果糖呈指数形式排空，且比其他糖类排空得更快。当在猴子每日4小时的进食期之前给予这些糖类的溶液（150毫升中含37.5克）时，每种糖类导致的食物摄入量总减少量相似。然而，果糖在进食的前2小时对食物摄入的抑制作用比其他糖类小，就如同它对胃排空的抑制作用较小一样。D-木糖虽然在实验当天的胃排空和进食方面模拟了葡萄糖，但由于其代谢不良，在随后的对照日产生了热量不足，随后被暴饮暴食所取代。我们从葡萄糖和木糖之间的相似性得出结论，胃在排空营养物质时会影响进食，并且至少可以是吸收前饱腹感和热量稳态信号的一个来源。果糖的研究结果表明，尽管胃排空特性不同，但其他部位必须发挥作用才能实现对进食的类似调节。
