Glial cells, but not interstitial cells, express P2X7, an ionotropic purinergic receptor, in rat gastrointestinal musculature.
Purinergic (ATP) neurotransmission is a component of the inhibitory response of the musculature in various regions of the gastrointestinal tract. So far, seven ionotropic purinergic receptors (P2X1-7) have been cloned. As specific antibodies become available, their respective distribution in the gastrointestinal tract can be elucidated. Here, we used high-resolution tricolor confocal microscopy, to study the distribution of P2X7-immunoreactive (-ir) cells in the muscularis propria of the rat stomach, small intestine, and colon. Smooth muscle cells, KIT-ir interstitial cells of Cajal, and CD34/SK3-ir fibroblastlike cells were P2X7-negative, whereas P2X7 immunoreactivity was observed in nerves and S100-ir glial cells. In all regions studied, P2X7 immunoreactivity was also observed in myenteric and submucosal ganglia, where perineuronal nerve endings appeared brightly labeled. Our observations suggest that purinergic signaling could influence the enteric glia through P2X7 receptors.
Vanderwinden
Jean-Marie
JM
Laboratoire de Neurophysiologie, Faculté de Médecine, Université Libre de Bruxelles, Campus Erasme, CP 601, 808 Route de Lennik, B-1070 Brussels, Belgium. jmvdwin@ulb.ac.be
Timmermans
Jean-Pierre
JP
Schiffmann
Serge N
SN
D000818:Animals; D004064:Digestive System / Q000378:metabolism*; D005347:Fibroblasts / Q000187:drug effects / Q000378:metabolism; D019084:Fluorescent Antibody Technique, Indirect; D005456:Fluorescent Dyes; D007150:Immunohistochemistry; D066298:In Vitro Techniques; D008297:Male; D018613:Microscopy, Confocal; D009130:Muscle, Smooth / Q000378:metabolism*; D009457:Neuroglia / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar; D018048:Receptors, Purinergic P2 / Q000096:biosynthesis*; D058486:Receptors, Purinergic P2X7
D005456:Fluorescent Dyes; C546470:P2rx7 protein, rat; D018048:Receptors, Purinergic P2; D058486:Receptors, Purinergic P2X7