Hamilton D L, Roe W E, Nielsen N O
Can J Comp Med. 1977 Jul;41(3):306-17.
Acute, isolated loops of proximal and distal jejunum of weanling swine were exposed to either heat stable porcine Escherichia coli enterotoxin, heat labile porcine Escherichia coli enterotoxin, cholera toxin or theophylline. Unidirectional sodium fluxes in response to heat stable in the proximal jejunum were dependent on the length of time that the intestinal mucosae was exposed to the enterotoxin. Net water, sodium and chloride and unidirectional sodium and chloride flux measurements in the proximal jejunum in response to each agent uniformly indicated that net secretion of fluid and electrolytes was the result of increased unidirectional sodium secretion or blood-to-lumen flux and decreased unidirectional chloride absorption or lumen-to-blood flux. In addition heat stable cholera toxin and theophylline but not heat labile decreased unidirectional chloride secretion a small but significant amount in the proximal jejunum. Sodium and chloride flux measurements in the distal jejunum demonstrated that all four secretory agents could stimulate net secretion of water, sodium and chloride in that region. The response to these secretory agents as measured by sodium and chloride unidirectional flux rates was not similar to changes observed in the proximal jejunum. In the distal small intestine, whereas heat labile cholera toxin and theophylline induced similar qualitative changes in unidirectional sodium and chloride fluxes, that induced by heat stable differed.
将断奶仔猪的近端和远端空肠急性分离出肠袢，分别暴露于热稳定型猪大肠杆菌肠毒素、热不稳定型猪大肠杆菌肠毒素、霍乱毒素或茶碱中。近端空肠对热稳定型肠毒素的单向钠通量取决于肠黏膜暴露于肠毒素的时间长度。对每种试剂的反应中，近端空肠的净水、钠和氯以及单向钠和氯通量测量均一致表明，液体和电解质的净分泌是单向钠分泌增加或血到腔通量增加以及单向氯吸收减少或腔到血通量减少的结果。此外，热稳定型霍乱毒素和茶碱，但不是热不稳定型，在近端空肠中使单向氯分泌少量但显著减少。远端空肠的钠和氯通量测量表明，所有四种分泌剂均可刺激该区域水、钠和氯的净分泌。通过钠和氯单向通量率测量的对这些分泌剂的反应与近端空肠中观察到的变化不同。在远端小肠中，热不稳定型霍乱毒素和茶碱在单向钠和氯通量中引起相似的定性变化，而热稳定型引起的变化则不同。
