[Sensory fibers sensitive to capsaicin can modulate secretion of the duodenal mucus. A morphometric study in rats].
Many in vitro and in vivo models have been used to study the modulation of intestinal mucosecretion. In such studies, quantification of mucus secretion is usually difficult, due to several technical problems. Whether sensory mechanisms participate in the modulation of intestinal mucosecretion remains unknown. The development and assessment of a morphometric method with computer assisted image analysis that allows to detect and quantitate mucin secretion by duodenal goblet cells are reported. Using this method, the secretory effect of pilocarpine on villus and crypt goblet cells was confirmed. We also determined whether sensory neurons can regulate intestinal mucosecretion by using capsaicin, a vegetal neurotoxin specific of a subpopulation of afferent primary sensory neurons. Intravenous capsaicin administration (10 micrograms/kg) increased mucus secretion by the goblet cells of the duodenal crypts. This suggests that sensory neurons may modulate duodenal mucin secretion. The "local effector function" of these neurons might be involved, in part through the release of substance P because exogenous substance P was able to increase mucin excretion by goblets cells of duodenal villi. Substance P, however, did not exactly mimic the capsaicin effects, suggesting that other factors were involved.
Laporte
J L
JL
INSERM U239, Faculté de Médecine X.-Bichat, Paris.
Dauge-Geffroy
M C
MC
Chariot
J
J
Rozé
C
C
Potet
F
F
D000818:Animals; D002211:Capsaicin / Q000494:pharmacology*; D004386:Duodenum / Q000187:drug effects*; D007413:Intestinal Mucosa / Q000187:drug effects* / Q000294:innervation / Q000378:metabolism; D007419:Intestinal Secretions / Q000187:drug effects*; D008297:Male; D009475:Neurons, Afferent / Q000187:drug effects*; D010862:Pilocarpine / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D013268:Stimulation, Chemical; D013373:Substance P / Q000494:pharmacology
D010862:Pilocarpine; D013373:Substance P; D002211:Capsaicin