Modified absorptive and secretory processes in the rat distal colon after neutron irradiation: In vivo and in vitro studies

Citation
A. Francois et al., Modified absorptive and secretory processes in the rat distal colon after neutron irradiation: In vivo and in vitro studies, RADIAT RES, 151(4), 1999, pp. 468-478
Citations number
45
Categorie Soggetti
Experimental Biology
Journal title
RADIATION RESEARCH
ISSN journal
00337587 → ACNP
Volume
151
Issue
4
Year of publication
1999
Pages
468 - 478
Database
ISI
SICI code
0033-7587(199904)151:4<468:MAASPI>2.0.ZU;2-9
Abstract
Impaired fluid and electrolyte transport in the intestine is a well-recogni zed characteristic of radiation-induced pathologies in the gastrointestinal tract. The aim of this study was to investigate the responsiveness of the epithelium of the colon of the rat to electrical and pharmacological (serot onin, carbachol) stimulation concomitantly with in vivo assessment of the a bsorptive capacity of the colon at 1, 3, 5 and 7 days after 3.8 Gy whole-bo dy exposure to neutrons, The responsiveness of rat colon in vitro to electr ical stimulation and the number of mast cells were measured to examine the role of neuroimmune networks in radiation-induced dysfunction, Animals show ed an impaired capacity of the colon to absorb water and sodium from 3 to 5 days after irradiation together with decreased responsiveness to electrica l and pharmacological stimulation. The time course of decreased responsiven ess to neural stimulation was similar to that of impaired absorption observ ed in vivo, but it was not correlated with variations in mast cell numbers, Histological (mast cells) and biochemical analyses (myeloperoxidase and NO synthase activities) did not find evidence of a marked infiltration and/or activation of inflammatory cells. Thus the impaired absorptive capacity of the colon observed after irradiation occurs concomitantly with decreased n eural influence, and is possibly related to reduced epithelial functional c apacity but not to decreased mast cell numbers. (C) 1999 by Radiation Resea rch Society