Abstract
Interstitial cells in the deep muscular plexus (ICC-DMP) are thought to be essential for neurotransmission in the circular muscle. There is evidence for gap junctions within the ICC-DMP network and between ICC-DMP and muscle cells; however, there is no evidence for functional coupling via these gap junctions. In addition, the innervation of individual ICC-DMP has not been studied. We investigated these questions by injecting the dye Lucifer yellow into ICC-DMP of guinea-pig ileum. Nerves were labelled immunohistochemically for protein gene product 9.5. Cells were imaged by confocal microscopy. Most (79%) of the dye-injected ICC-DMP were coupled to one to five other ICC-DMP, and 86% of them were coupled to one to five circular muscle cells. Octanol effectively blocked all coupling. Incubation in pH 6.8-7.0 reduced ICC-ICC coupling to 49% and ICC-muscle coupling to 32%. In contrast, pH 7.8-7.9 increased ICC-ICC and ICC-muscle coupling to 100%. Most ICC somata (95%) and processes (60%) were in close proximity with both nerve fibres and smooth muscle cells. These results provide direct evidence for functional coupling within the ICC-DMP network, and between this network and cells of the outer circular muscle layer and showed that coupling can be affected by pH.
Original language | English (US) |
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Pages (from-to) | 635-641 |
Number of pages | 7 |
Journal | Neurogastroenterology and Motility |
Volume | 15 |
Issue number | 6 |
DOIs | |
State | Published - Dec 2003 |
Keywords
- Gap junctions
- Immunohistochemistry
- Small intestine
ASJC Scopus subject areas
- Physiology
- Endocrine and Autonomic Systems
- Gastroenterology