Immunohistochemical evidence for the presence of calbindin containing neurones in the myenteric plexus of the guinea-pig stomach

Using immunohistochemistry we studied the presence of calbindin in myenteri c neurones of the guinea-pig stomach. A rabbit anti recombinant rat calbind in-D28k (CALB) stained 12, 12 and 25% of all myenteric neurones in the fund us, corpus and antrum, respectively. A rabbit anti recombinant human CALB s tained 4, 4 and 16%, respectively. A mouse monoclonal antibody against the chicken intestinal CALB showed no labelling. In all regions most calbindin neurones were additionally choline acetyltransferase (ChAT) positive while only a small proportion exhibited nicotinamide adenosine dinucleatide phosp hate (NADPH)-diaphorase-activity. Numerous calbindin -positive varicose ner ve fibres were present within myenteric ganglia, rarely detectable in the m uscle layers and virtually absent in the mucosa. This study demonstrated th at a supopulation of cholinergic myenteric neurones in the stomach contain calbindin and suggested that many of these neurones fulfil interneuronal ta sks. (C) 1999 Elsevier Science ireland Ltd. All rights reserved.