Serotonin-induced short-circuit current in pig jejunum.
This paper presents the effects of serotonin (5-HT) on short-circuit current (SCC), sodium and chloride fluxes, and prostaglandin E2 release in pig jejunum, using the Ussing-chamber technique. 5-HT elicited a dose-dependent increase in SCC, yielding an EC50 of 6 +/- 4 microM and EMAX of 77 +/- 8 microA.cm-2 using about 100 microM. Inhibited sodium absorption and stimulated chloride secretion carried part of the 5-HT-induced SCC. 5-HT caused a dose-independent PGE2 release, and indomethacin reduced the SCC-inducing effect of 5-HT by 40%. Octreotide, a long-lasting somatostatin analogue, also reduced 5-HT-induced SCC by about 40%, while tetrodotoxin (TTX) did not alter the effect of 5-HT. In conclusion, 5-HT causes a dose-dependent indomethacin and octreotide-sensitive, and TTX-insensitive increase in SCC, and a chloride secretion and inhibited sodium absorption and an increased release of PGE2 in pig jejunum in vitro.
Hansen
M B
MB
Department of Anatomy and Physiology, Royal Veterinary and Agricultural University, Frederiksberg C, Denmark.
Thorbøll
J E
JE
Christensen
P
P
Bindslev
N
N
Skadhauge
E
E
D000818:Animals; D001693:Biological Transport, Active / Q000187:drug effects; D015232:Dinoprostone / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004594:Electrophysiology; D007408:Intestinal Absorption / Q000187:drug effects; D007583:Jejunum / Q000187:drug effects* / Q000502:physiology; D012701:Serotonin / Q000494:pharmacology*; D013552:Swine / Q000502:physiology*
D012701:Serotonin; D015232:Dinoprostone