Neuropeptide modification of chloride secretion in guinea pig distal colon

https://doi.org/10.1016/0167-0115(87)90072-3Get rights and content

Abstract

This study examined the effects of electrically stimulating submucosal neurons in the guinea pig isolated distal colonic mucosa and determined the effects of several peptides that are present in these neurons. Electrical field stimulation of muscle-stripped segments of guinea pig distal colonic mucosa, set up in Ussing flux chambers, evoked an increase in short-circuit current (Isc), of 371 ± 31 μA · cm−2. The response to electrical stimulation was abolished by tetrodotoxin and significantly reduced by serosal furosemide. Atropine reduced, but did not abolish, the neurally evoked response. Addition of neuropeptide Y and galanin to the serosal bath had no effect on baseline Isc, but both evoked a concentration-dependent decrease in the neurally evoked secretory response. Vasoactive intestinal polypeptide evoked a concentration-dependent increase in basal (unstimulated) Isc that was reduced by furosemide and unaltered by tetrodotoxin. Neuropeptide Y, but not galanin, significantly reduced the secretory responses to vasoactive intestinal polypeptide and bethanechol. Somatostatin 201–995 and human calcitonin gene-related peptide had no effect on basal Isc nor did either alter the neurally evoked response. These results suggest that acetylcholine and non-cholinergic neurotransmitter(s) stimulate chloride secretion in the guinea pig distal colonic mucosa. This neurosecretory response may be modulated by neuropeptide Y and galanin that are found within submucosal neurons.

References (22)

  • J.B. Furness et al.

    Neurochemically similar myenteric and submucosal neurons directly traced to the mucosa of the small intestine

    Cell Tissue Res.

    (1985)
  • Cited by (29)

    • Peptide YY as a growth factor for intestinal epithelium

      2002, Peptides
      Citation Excerpt :

      In order for PYY to be able to exert a biological effect directly on a cell, that cell must express cell surface receptors that specifically bind PYY. Studies using whole gut tissue or stripped mucosa preparations showed that PYY or NPY could inhibit short circuit current or apical chloride secretion in a variety of species including the rabbit [6,21,22,34], rat [16,60], guinea pig [49], and human [50]. However, it was not possible to tell whether PYY or NPY had direct effects on the epithelial cells, consistent with epithelial cell expression of Y receptors, or whether the PYY effects were indirectly exerted by intervening neurotransmitter or other gut peptide networks included in the tissue preparation (even if PYY/NPY responses persisted after tetrodotoxin administration).

    View all citing articles on Scopus
    View full text