Related Experiment Video
Updated: Apr 28, 2026

In vitro Functional Characterization of Mouse Colorectal Afferent Endings
Published on: January 21, 2015
Multiple immunoreactive forms of vasoactive intestinal peptide in human colonic mucosa
Abstract:
Extracts of human colon mucosa and muscle were fractionated by gel filtration and ion exchange chromatography and molecular forms of vasoactive intestinal peptide (VIP) estimated by radioimmunoassay. Total concentrations of immunoreactive VIP in mucosa were 237.1 +/- 53.9 and 119 +/- 26.0 pmoles per g in muscle. In muscle, over 90% of the immunoreactivity was accounted for by a single component indistinguishable from porcine VIP by gel filtration and ion exchange chromatography. In contrast, mucosa contained four components with VIP-like immunoreactivity. One of these had the chromatographic properties of porcine VIP; the others were less positively charged. Two of the new VIP-like components had gel filtration properties similar to those of VIP and are, therefore, probably of similar size to the porcine octacosapeptide, and the remaining component emerged later on Sephadex and is, therefore, probably a smaller peptide. Immunoreactive VIP in muscle extracts is believed to originate from nerve fibers, and this form of VIP is likely to be identical to the previously characterized form of VIP. However, immunoreactive VIP in mucosal extracts may originate either from endocrine cells or nerve fibers. The possibility arises, then, that there are different immunoreactive forms of VIP in nerves and endocrine cells.
More Related Videos
Related Concept Videos
Renewal of Intestinal Stem Cells
Microvilli
These microvilli are predominantly present in cells lining the small intestine, kidney tubules, and certain cells in the respiratory and reproductive systems. By significantly expanding the surface area of the cell membrane, microvilli enhance the cell's capacity...
Mucosal Barrier of the Stomach
Within parietal cells, carbonic acid is first formed through the reaction of water and carbon dioxide. The dissociation of carbonic acid releases bicarbonate and hydrogen ions. The bicarbonate...
Histology of the Small Intestine
The intestinal lining features transverse folds called circular folds, each housing fingerlike projections known as intestinal villi. These villi are covered by a layer of simple columnar epithelium, also referred to as...
Inflammatory Bowel Disease II: Ulcerative Colitis
Inflammatory Bowel Disease IV: Clinical Manifestations

