McLeay L M, Comeskey M A, Waters M J
Department of Biological Sciences, University of Waikato, Hamilton, New Zealand.
J Endocrinol. 1990 Jan;124(1):109-15. doi: 10.1677/joe.0.1240109.
Adult sheep were infused with depilating doses of epidermal growth factor (EGF) at 4 micrograms/kg per h for 24 h. Food was available ad libitum during recording of integrated electromyographic (EMG) activity of the gastrointestinal tract. In comparison with control sheep infused with saline, EGF reduced the frequency of A and B sequences of contraction of the reticulum and rumen over the 24-h period, an effect attributable to the consumption of less food. During the 24-h infusion, EGF stimulated phase III migrating myoelectric complex (MMC)-like activity of the duodenum with an associated decline in the EMG of the abomasal antrum. Infusion of EGF for 1 h at 2.5 and 5.0 micrograms/kg per h in fasted animals produced inhibitory effects on the frequency of A sequences of contraction of the reticulum and rumen during the infusion, and on the amplitude of the ruminal EMG during, and in the hour following, infusion. Phase III MMC-like activity of the duodenum was stimulated by EGF in fasted animals. It is concluded that in fed sheep, depilating doses of EGF have inhibitory effects on the EMG activity of the reticulum and rumen through reductions in food consumption and by other undefined mechanisms. Additional effects of EGF on the gastrointestinal tract of sheep include stimulation of duodenal phase III MMC-like activity.
对成年绵羊以每小时4微克/千克的剂量注入脱毛剂量的表皮生长因子（EGF），持续24小时。在记录胃肠道综合肌电图（EMG）活动期间，食物可随意获取。与注入生理盐水的对照绵羊相比，EGF在24小时内降低了网胃和瘤胃收缩的A序列和B序列的频率，这种作用归因于食物摄入量减少。在24小时的注入过程中，EGF刺激十二指肠的Ⅲ期移行性复合肌电活动（MMC），同时皱胃窦部的肌电图活动下降。在禁食动物中，以每小时2.5微克/千克和5.0微克/千克的剂量注入EGF 1小时，对注入期间网胃和瘤胃收缩的A序列频率以及注入期间和注入后1小时瘤胃肌电图的振幅产生抑制作用。禁食动物的十二指肠Ⅲ期MMC样活动受到EGF的刺激。得出的结论是，在喂食的绵羊中，脱毛剂量的EGF通过减少食物摄入量和其他未明确的机制对网胃和瘤胃的肌电图活动产生抑制作用。EGF对绵羊胃肠道的其他作用包括刺激十二指肠Ⅲ期MMC样活动。
