Specialized pacemaking cells in the human Fallopian tube.

It is postulated that the propagated electric activity of the gut is generated by the interstitial cells of Cajal (ICCs). We investigated the hypothesis of the presence of ICCs in the Fallopian tube (FT) as initiators of the tubal electric activity. Specimens from various parts of the FT were obtained from 21 female cadavers (mean age 38.2 +/-10.9 years) from the PostMortem Department of the Cairo University, Faculty of Medicine. Fixed sections were prepared and stained for c-kit. Controls for antisera specificity consisted of tissue incubated with normal rabbit serum substituted for the primary antiserum. Dendritic, c-kit-positive, ICC-like cells were detected in the tubal musculature of the studied specimens. They were distinguishable from the c-kit-positive nonbranching mast cells and from the c-kit-negative smooth muscle cells (SMC). Immunoreactivity was absent in the negative controls. We have for the first time identified cells in the FT with morphologic and immunologic phenotypes similar to the ICCs of the gut. These cells may be responsible for initiating the slow waves (SWs) recorded from the SMC of the FT. This is a preliminary study, and further studies are needed to investigate the functional role of these cells.