Disruption of interstitial cells of Cajal networks after massive small bowel resection

Figure 1 c-kit immunopositivity at the level of the myenteric plexus in ileal whole-mount preparations. A: In the sham-operated group, c-kit-positive cells were predominantly present at the myenteric plexus level; B: Compared with sham-operated tissues, the number and density of c-kit immunopositive cells were significantly decreased in the short bowel syndrome (SBS) 1W group; C: In the SBS2W group, the number of interstitial cells of Cajal had returned to normal levels. The arrows showed c-kit immunoexpression is positive (original magnification × 400). LM: Longitudinal muscle; CM: Circular muscle.

Figure 2 Ultrastructural morphological changes in interstitial cells of Cajal. A: At the ultrastructural morphological level, interstitial cells of Cajal (ICC) showed typical myofilaments and organelles of ICC, such as mitochondria and smooth sarcoplasmic reticulum in the sham-operated group; B: Ultrastructural changes of ICC were observed in the short bowel syndrome (SBS) 1W group, such as clear cytoplasm, sparse mitochondria, scarce smooth endoplasmic reticulum and a reduced number of contacts between nerves and ICC; C: In the SBS2W group, ultrastructural changes of ICC were ameliorated (original magnification × 3750, 2.5 K). SMC: Smooth muscle cell; GJ: Gap junction; M: Mitochondria; MG: Myenteric ganglion.

Figure 3 Electrical activity recorded from the small intestines (ileum) from sham-operated and short bowel syndrome rats. A: Slow waves in sham-operated group were biphasic, consisting of an upstroke and plateau component. Slow waves short bowel syndrome (SBS) 1W rats lacked an obvious secondary component; B: Resting membrane potentials (RMP) in each group were recorded, and a depolarized membrane potential appears to be a common feature of intestine smooth muscle in SBS rats; C: Slow wave frequency; D: Slow wave amplitude. ^aP < 0.05 vs sham group (n = 7).

Figure 4 Changes in the expression profile of c-kit and membrane-bound stem cell factor in response to massive small bowel resection. A, C: The protein expression levels of c-kit and membrane-bound stem cell factor (mSCF) were downregulated in the first week after massive small bowel resection in the short bowel syndrome (SBS) 1W group and increased in the second week of the SBS2W group; B, D: Relative expression was determined by normalization to glyceraldehyde-3-phosphate dehydrogenase (GAPDH). ^aP < 0.05 vs sham group (n = 4).