Opleta-Madsen K, Hardin J, Gall D G
Intestinal Disease Research Unit, University of Calgary, Alberta, Canada.
Am J Physiol. 1991 Jun;260(6 Pt 1):G807-14. doi: 10.1152/ajpgi.1991.260.6.G807.
The role of epidermal growth factor (EGF) in the acute regulation of intestinal transport of electrolytes and glucose was examined. In vivo transport studies were performed in New Zealand White rabbits (500-900 g) using a single-pass perfusion technique. In vitro net fluxes were determined under short-circuited conditions in Ussing chambers. Kinetic parameters of glucose transport in the presence and absence of EGF were measured in brush-border membrane vesicles. In vivo studies showed that the addition of 60 ng/ml EGF to the perfusate resulted in increased absorption of H2O, Na+, Cl-, and glucose from the jejunum. In Ussing chambers, the presence of EGF caused an increase in jejunal net fluxes of glucose-stimulated Na+ and 3-O-methylglucose due to an increase in mucosal-to-serosal movements. Verapamil abolished the EGF effect. In the absence of glucose, net fluxes of Na+ and Cl- were enhanced in the presence of EGF due to a decrease in the serosal-to-mucosal movement of both ions. Verapamil had no effect on this decrease. The incubation of EGF with brush-border membrane vesicles had no effect on either the maximal flux or the Michaelis constant of glucose transport. These results indicate that EGF is capable of regulating absorption of electrolytes and nutrients from the small intestine and suggest a role for this peptide in the control of intestinal transport.
研究了表皮生长因子（EGF）在急性调节肠道电解质和葡萄糖转运中的作用。采用单通道灌注技术，对体重500 - 900克的新西兰白兔进行体内转运研究。在Ussing室中，在短路条件下测定体外净通量。在有和没有EGF的情况下，测量刷状缘膜囊泡中葡萄糖转运的动力学参数。体内研究表明，向灌注液中添加60 ng/ml EGF会导致空肠对水、钠、氯和葡萄糖的吸收增加。在Ussing室中，由于粘膜到浆膜的转运增加，EGF的存在导致葡萄糖刺激的钠和3 - O - 甲基葡萄糖的空肠净通量增加。维拉帕米消除了EGF的作用。在没有葡萄糖的情况下，由于两种离子从浆膜到粘膜的转运减少，EGF存在时钠和氯的净通量增加。维拉帕米对这种减少没有影响。EGF与刷状缘膜囊泡孵育对葡萄糖转运的最大通量或米氏常数均无影响。这些结果表明，EGF能够调节小肠中电解质和营养物质的吸收，并提示该肽在控制肠道转运中发挥作用。
