Determination of the source of increased serotonin (5-HT) concentrations in blood and peritoneal fluid of colic horses with compromised bowel.
Equine Vet J
; 40(4): 326-31, 2008 Jun.
Article
en En
| MEDLINE
| ID: mdl-18321805
ABSTRACT
REASONS FOR PERFORMING STUDY Increased plasma (5-HT) concentrations are reported in horses predisposed to develop laminitis and after i.v. infusion of endotoxins. In the equine jejunum contractile 5-HT1A-like receptors show tachyphylaxia upon prolonged activation with 5-HT. Therefore, increased systemic 5-HT release in colic horses could play a possible role in the pathophysiology of ileus. OBJECTIVE:
To investigate possible increased systemic release of 5-HT in colic horses with compromised bowel and to identify the source of 5-HT overload.METHODS:
Concentrations of 5-HT were determined in plasma and peritoneal fluid (PF) of healthy horses (n = 10), strangulating small intestinal colic horses (n = 18), nonsurgical colic horses (n = 10) and cryptorchid stallions (n = 6). It was attempted to identify the source of 5-HT overload by comparing the blood and PF 5-HT concentrations within horses and by assessing the in vivo platelet activation through determination of the beta-thromboglobulin (beta-TG)/platelet factor 4 (PF4) ratio.RESULTS:
All horses in the strangulating small intestinal colic group had plasma (P = 0.006) and PF (P = 0.01) 5-HT concentrations above those found in the control group. Plasma beta-TG/PF4 ratio in these horses exceeded 2 in all cases, indicating in vivo platelet activation. Concentrations of 5-HT in PF of colic horses with compromised bowel were significantly lower than the corresponding plasma concentrations (P = 0.005). POTENTIAL RELEVANCE In horses with compromised bowel, significant amounts of 5-HT can be released into the systemic circulation, through massive release of platelet-stored 5-HT. 5-HT is a very potent proinflammatory, vasoconstrictive and immunomodulatory agent. In view of the rapid and prolonged tachyphylaxia, shown for the jejunal 5-HT1A-like receptors, this increased systemic 5-HT release could play a role in the pathophysiology of ileus in horses.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Líquido Ascítico
/
Serotonina
/
Cólico
/
Ileus
/
Enfermedades de los Caballos
Tipo de estudio:
Observational_studies
/
Prognostic_studies
Límite:
Animals
Idioma:
En
Revista:
Equine Vet J
Año:
2008
Tipo del documento:
Article
País de afiliación:
Bélgica