Myoelectric activity and absorptive capacity of rat small intestinal isografts

The effect of transplantation on small intestinal absorption, digestive capacity, myoelectric activity, and morphology was assessed in inbred Lewis rats. Electrodes were sutured to the duodenum and isografted jejunoileum or to the native jejunoileum in controls. The frequency of migrating myoelectric complexes (MMCs) in the duodenum was 3.3 ± 0.3/hr in controls and 1.8 ± 0.4/hr in transplants (P < 0.05). MMC frequency in the jejunoileum was 5.1 ± 1.3/hr in controls and 3.2 ± 0.9/hr in transplants (P > 0.05). MMCs appeared to migrate from the duodenum to the jejunoileum 80 ± 3% of the time in controls and 59 ± 7% of the time in transplant rats (P < 0.05). Absorption in the transplanted jejunoileum demonstrated a 35-40% decrease in glucose and electrolytes absorption. Villus height and number of nuclei per villus was reduced. Intestinal length (dry) was 103 ± 6 cm for controls and 51 ± 3 cm for transplant rats (P < 0.05). Brush border sucrase activity was unchanged. We conclude that small intestinal isografts display similar myoelectric activity as controls, but the decreased absorptive capacity and villus height may require longer segments of intestine to be transplanted in order to support normal nutrition.