Fig. 7. Effects of mesenteric nerve transection on the retrograde giant contraction (RGC). This figure depicts the effects of mesenteric nerve transection at J40 to J75 cm from the pylorus on the initiation, generation, and propagation of the RGC across the small intestine. Mesenteric nerve transection preserved the RGC over 10 cm from J40 to J50, blocked the RGC at J70, and reduced the magnitude and duration of the RGC at J80, J90, and J100. However, unlike myotomy the RGC sequence across the denervated intestine was not altered. This is unlike myotomy, as the RGC aborad of the transection did not occur after initiation of the RGC orad of the denervation. Mesenteric nerve transection had no observable effects orad of the transected intestine. Mesenteric nerve transection also blocked the intestino-intestinal inhibitory reflex that allowed non-RGC contractions to occur during the propagation of the RGC, ie, between the vertical bars, which never occurred when the mesenteric nerve was intact. P3, phase III of the migrating motor complex; D, duodenum; J, jejunum. The numbers after the letters indicate the cm from the pylorus of the strain gauge. Adapted from Lang.
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