F. Karmeli et al., EFFECT OF COLCHICINE AND BISACODYL ON RAT INTESTINAL TRANSIT AND NITRIC-OXIDE SYNTHASE ACTIVITY, Scandinavian journal of gastroenterology, 32(8), 1997, pp. 791-796
Background: Bisacodyl and colchicine affect smooth-muscle contractilit
y, intestinal water, and electrolyte transport. Nitric oxide (NO) stim
ulates intestinal electrolyte secretion and has an important role as a
mediator of intestinal motility. We therefore studied, in rats, the e
ffects of these agents on nitric oxide synthase (NOS) activity and gas
trointestinal transit. Methods: Rats were treated with bisacodyl (10 m
g/kg intragastrically) or colchicine (5 mg/kg intraperitoneally) with
or without pretreatment with ketotifen (1 mg/kg intragastrically). Rat
s were killed after 1, 2, and 4 h. The intestine was isolated and rins
ed, the mucosa scraped, and NOS activity determined. In all rats small
-intestinal transit was measured 15 min after intragastric administrat
ion of charcoal. Results: Bisacodyl (10 mg/kg) and colchicine (5 mg/kg
) induced a significant decrease in jejunal NOS activity. Pretreatment
with the mast cell stabilizer ketotifen, which has been shown to atte
nuate the increased permeability induced by NO inhibition, prevented t
he decrease in colonic and jejunal NOS activity induced by bisacodyl a
nd colchicine. Bisacodyl and colchicine significantly decreased intest
inal transit time. Their effect on transit time was similar to that in
duced by intravenous administration of N-G-nitro-L-arginine methyl eat
er (10 mg/kg). Conclusions: It is suggested that the effect of bisacod
yl and colchicine on intestinal transport is, at least partly, mediate
d through NO inhibition.