Wapnir R A, Zdanowicz M M, Teichberg S, Lifshitz F
Department of Pediatrics, North Shore University Hospital-Cornell University Medical College, Manhasset, New York 11030.
J Pediatr Gastroenterol Nutr. 1990 Feb;10(2):213-21. doi: 10.1097/00005176-199002000-00012.
We investigated the effectiveness of L-alanine (Ala) addition to oral hydration solutions (OHSs) during secretory conditions induced by ileal instillation of 10 mM theophylline in anesthetized rats using a perfusion procedure, and monitoring water and sodium transport. Ala was added to two hypotonic OHSs in which the sodium:glucose ratio was 2:1, and compared with the OHS recommended by the World Health Organization (WHO), which has a sodium:glucose ratio of 0.81:1. Theophylline had the expected secretory effect on water and sodium absorption in the WHO-recommended OHS, and on sodium transport in a formula containing 60 mM sodium and 30 mM glucose. However, an OHS with 90 mM sodium and 45 mM glucose canceled the secretory effect of theophylline and yielded a greater rate of net water absorption than the WHO formula. Addition to this solution of either 15 or 30 mM Ala enhanced water and sodium absorption of both control and theophylline-treated rats. In the hypotonic OHS with 60 mM sodium and 30 mM glucose, Ala had little effect on both sodium and water transport. Therefore, the data support the view that Ala added to solutions with 90 mM sodium, containing sufficient glucose to maintain a sodium:glucose ratio of not less than 2:1, is most effective at compensating fluid and sodium losses under secretory conditions. Ala presumably exerts its sodium-sparing effect because of its cotransport with sodium and the consequent water influx into the intestinal cells.
我们采用灌注程序，在麻醉大鼠回肠灌注10 mM茶碱诱导的分泌状态下，研究了在口服补液溶液（OHS）中添加L-丙氨酸（Ala）的效果，并监测水和钠的转运。将Ala添加到两种钠：葡萄糖比例为2：1的低渗OHS中，并与世界卫生组织（WHO）推荐的钠：葡萄糖比例为0.81：1的OHS进行比较。茶碱对WHO推荐的OHS中的水和钠吸收以及含60 mM钠和30 mM葡萄糖配方中的钠转运具有预期的分泌作用。然而，含90 mM钠和45 mM葡萄糖的OHS消除了茶碱的分泌作用，并且比WHO配方产生了更高的净吸水速率。向该溶液中添加15 mM或30 mM Ala均可增强对照大鼠和经茶碱处理大鼠的水和钠吸收。在含60 mM钠和30 mM葡萄糖的低渗OHS中，Ala对钠和水的转运几乎没有影响。因此，数据支持以下观点：在含90 mM钠且含有足够葡萄糖以维持钠：葡萄糖比例不低于2：1的溶液中添加Ala，在分泌状态下补偿液体和钠损失最为有效。Ala可能因其与钠的协同转运以及随之而来的水流入肠细胞而发挥其保钠作用。
