A selective, high affinity 5-HT 2B receptor antagonist inhibits visceral hypersensitivity in rats.
Neurogastroenterol Motil
; 22(2): e69-76, 2010 Feb.
Article
en En
| MEDLINE
| ID: mdl-19740115
ABSTRACT
BACKGROUND:
RS-127445 is a selective, high affinity 5-HT(2B)receptor antagonist. We investigated whether 5-HT(2B)receptor antagonists can reduce colonic visceral hypersensitivity caused by restraint stress or by proximal colonic inflammation.METHODS:
Visceral hypersensitivity was induced in rats by either restraint stress or injection of 2, 4, 6-trinitrobenzene sulfonic acid (TNBS) into the proximal colon. Restraint stress produced a significant increase in numbers of abdominal contractions evoked by colorectal distension (CRD), measured as a quantitative index of visceral nociception in rats. Seven days after TNBS injection, the pain threshold to CRD at the non-inflamed distal colon, that was determined as the minimum pressure required to evoke abdominal cramp, was significantly decreased. The effect of RS-127445 on visceral hypersensitivity was assessed in either naïve or TNBS-treated rats. KEYRESULTS:
Oral administration of a selective, high affinity 5-HT(2B)receptor antagonist, RS-127445, significantly inhibited visceral hypersensitivity provoked by restraint stress (35 to 74% inhibition at 1 to 10 mg kg(-1)). Oral RS-127445 produced a significant suppression of TNBS-induced visceral hypersensitivity (15 to 62% inhibition at 3 to 30 mg kg(-1)), although it was without significant effect on the visceral nociceptive threshold of naïve rats. RS-127445 (1 to 30 mg kg(-1), p.o.) also dose-dependently reduced the restraint stress-induced defecation in naïve and TNBS-treated rats. CONCLUSIONS & INFERENCES These results suggest that 5-HT(2B)receptors are involved in signaling from the colon in rats in which there is visceral hypersensitivity and that a selective 5-HT(2B)receptor antagonist could have therapeutic potential for the treatment of gut disorders characterized by visceral hypersensitivity.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Colon
/
Receptor de Serotonina 5-HT2B
/
Antagonistas del Receptor de Serotonina 5-HT2
/
Hipersensibilidad
/
Contracción Muscular
/
Músculo Liso
Límite:
Animals
Idioma:
En
Revista:
Neurogastroenterol Motil
Asunto de la revista:
GASTROENTEROLOGIA
/
NEUROLOGIA
Año:
2010
Tipo del documento:
Article
País de afiliación:
Japón