Lugea A, Mourelle M, Domingo A, Salas A, Guarner F, Malagelada J R
Digestive System Research Unit, Hospital General Vall d'Hebron, Barcelona 08035, Spain.
Am J Physiol Gastrointest Liver Physiol. 2001 Apr;280(4):G774-9. doi: 10.1152/ajpgi.2001.280.4.G774.
Epidermal growth factor (EGF) is produced in Brunner's glands and plays a role in healing and repair of duodenal ulcers. We examined the participation of zwitterionic phospholipids of mucus in the effects of EGF. Under anesthesia, groups of rats received an intraduodenal bolus of either saline or EGF. Some rats received subcutaneous indomethacin followed by EGF or EGF followed by a detergent (5% Brij 35, a nonionic detergent that solubilizes luminal phospholipids). Thirty minutes after treatment, mucosal surface hydrophobicity and phospholipid concentration in the mucus layer were measured. Matched groups of rats were challenged with 0.5 M HCl, instilled intraduodenally 30 min after treatment, and mucosal damage was assessed 1 h after acid challenge. Exogenous EGF significantly increased surface hydrophobicity and phosphatidylcholine concentration in the mucus layer. EGF treatment also reduced mucosal damage induced by acid. However, indomethacin pretreatment or detergent administration after EGF abolished both protection against acid and changes in the mucus layer. These data suggest that EGF increases duodenal resistance to luminal acid via stimulation of mucosal zwitterionic phospholipids.
表皮生长因子（EGF）由十二指肠腺产生，在十二指肠溃疡的愈合和修复中发挥作用。我们研究了黏液中两性离子磷脂在EGF作用中的参与情况。在麻醉状态下，给大鼠十二指肠内注射生理盐水或EGF。一些大鼠先皮下注射吲哚美辛，然后注射EGF，或者先注射EGF，然后注射一种去污剂（5%的Brij 35，一种可溶解腔内磷脂的非离子去污剂）。治疗30分钟后，测量黏膜表面疏水性和黏液层中的磷脂浓度。在治疗30分钟后，给配对的大鼠十二指肠内注入0.5 M盐酸进行刺激，并在酸刺激1小时后评估黏膜损伤情况。外源性EGF显著增加了黏液层的表面疏水性和磷脂酰胆碱浓度。EGF治疗还减少了酸诱导的黏膜损伤。然而，EGF预处理后给予吲哚美辛或在EGF后给予去污剂，均消除了对酸的保护作用以及黏液层的变化。这些数据表明，EGF通过刺激黏膜两性离子磷脂来增加十二指肠对腔内酸的抵抗力。
