Changes in interstitial cells of Cajal at the deep muscular plexus are associated with loss of distention-induced burst-type muscle activity in mice infected by Trichinella spiralis.
The physiology and pathophysiology of the network of interstitial cells of Cajal associated with the deep muscular plexus (ICC-DMP) of the small intestine are still poorly understood. The objectives of the present study were to evaluate the effects of inflammation associated with Trichinella spiralis infection on the ICC-DMP and to correlate loss of function with structural changes in these cells and associated structures. We used immunohistochemistry, electron microscopy, and assessment of distention-inducing electrophysiological parameters in vitro. Damage to ICC-DMP was associated with a loss of distention-induced patterns of electrical activity normally associated with distention-induced peristalsis. Consistently, the timing of recovery of ICC-DMP paralleled the timing of recovery of the distention-induced activity. Nerve varicosities associated with ICC-DMP including cholinergic nerves, assessed by immunoelectron microscopy and whole mount double labeling, paralleled injury to ICC-DMP thus contributing to impaired excitatory innervation of smooth muscle cells. Major additional changes included a remodeling of the inner circular muscle layer, which may affect long-term sensitivity to distention after infection. In conclusion, transient injury to ICC-DMP in response to T. spiralis infection is severe and associated with a complete lack of distention-induced burst-type muscle activity.
Wang
Xuan-Yu
XY
Department of Medicine, McMaster University, Hamilton, ON, Canada.
Vannucchi
Maria-Giuliana
MG
Nieuwmeyer
Florentine
F
Ye
Jing
J
Faussone-Pellegrini
Maria-Simonetta
MS
Huizinga
Jan Dirk
JD
D000818:Animals; D004594:Electrophysiology; D004751:Enteritis / Q000469:parasitology / Q000473:pathology / Q000503:physiopathology*; D005769:Gastrointestinal Motility; D007421:Intestine, Small / Q000503:physiopathology*; D008297:Male; D026901:Membrane Transport Proteins / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D008854:Microscopy, Electron; D016253:Microscopy, Immunoelectron; D009119:Muscle Contraction / Q000502:physiology; D009130:Muscle, Smooth / Q000378:metabolism / Q000503:physiopathology* / Q000648:ultrastructure; D009197:Myenteric Plexus / Q000378:metabolism / Q000503:physiopathology*; D009412:Nerve Fibers / Q000648:ultrastructure*; D019009:Proto-Oncogene Proteins c-kit / Q000378:metabolism; D017160:Trichinella spiralis; D014235:Trichinellosis / Q000469:parasitology / Q000473:pathology / Q000503:physiopathology*; D050494:Vesicular Acetylcholine Transport Proteins
D026901:Membrane Transport Proteins; C493460:Slc18a3 protein, mouse; D050494:Vesicular Acetylcholine Transport Proteins; D019009:Proto-Oncogene Proteins c-kit