[Role of serotonin and histamine in the effects of degranulation of mast cells on the colonic motility and the transit. Experimental study in rats].
The aim of this work was to describe the alterations of colonic motility and transit induced by an experimental, histologically verified, degranulation of mast cells, provoked by the compound BrX-537A, and to determine the role of serotonin and histamine by specific antagonists, in the rat. Colonic myoelectrical activity was inhibited by BrX-537A (2 mg/kg IP) in a biphasic manner. The initial profound inhibition, lasting 30 min, during which the frequency of spike bursts decreased from 9.2 +/- 1.1 to 1.4 +/- 0.5/10 min, was followed by a sustained (5 h) period of moderate inhibition (5.2 +/- 0.5 spike bursts/10 min). In the same way, BrX-537A increased the mean retention time of a marker injected in the proximal colon (10.8 +/- 1.4 h vs 7.4 +/- 0.4 h). Neither serotoninergic nor histaminergic antagonists, at a dose of 1 mg/kg IP, modified the primary drastic inhibition of colonic motility during the first 20 minutes. After, a selective time-related blockade of this inhibition was observed. Granisetron blocked the inhibition from the 30th minute on, methysergide from the 120th minute on, and chlorpheniramine, between the 20th and 60th minutes. In conclusion, the inhibitory effect of mast cell degranulation depends on serotonin and histamine release, in a time-related manner, and implicates the H1, 5-HT3 and 5-HT1 or 2 receptors.
Castex
N
N
Laboratoire de Pharmacologie-Toxicologie, INRA, Toulouse.
Fioramonti
J
J
Fargeas
M J
MJ
Bueno
L
L
D000818:Animals; D000959:Antihypertensive Agents / Q000494:pharmacology; D015550:Cell Degranulation / Q000187:drug effects / Q000502:physiology*; D002744:Chlorpheniramine / Q000494:pharmacology; D003106:Colon / Q000187:drug effects / Q000502:physiology*; D005769:Gastrointestinal Motility / Q000187:drug effects / Q000502:physiology*; D005772:Gastrointestinal Transit / Q000187:drug effects / Q000502:physiology*; D017829:Granisetron / Q000494:pharmacology; D006632:Histamine / Q000502:physiology; D007832:Lasalocid / Q000031:analogs & derivatives / Q000494:pharmacology; D008297:Male; D008407:Mast Cells / Q000502:physiology*; D008784:Methysergide / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D012701:Serotonin / Q000502:physiology; D012702:Serotonin Antagonists / Q000494:pharmacology
D000959:Antihypertensive Agents; D002744:Chlorpheniramine; D017829:Granisetron; D006632:Histamine; D007832:Lasalocid; D008784:Methysergide; D012701:Serotonin; D012702:Serotonin Antagonists; C029086:bromolasalocid
Rôle de la sérotonine et de l'histamine dans les effets de la dégranulation des mastocytes sur la motricité et le transit coliques. Etude expérimentale chez le rat.