Ghrelin plays a minor role in the physiological control of cardiac function in the rat.
Endocrinology
; 144(5): 1787-92, 2003 May.
Article
en En
| MEDLINE
| ID: mdl-12697684
We have previously reported that a 7-d pretreatment with hexarelin, a synthetic ligand of the GH secretagogue receptor (GHS-R), largely prevented damages induced by ischemia and reperfusion in isolated rat hearts. Our aim was to ascertain whether ghrelin, an endogenous ligand of the GHS-R, is physiologically endowed with cardioprotective activity. Hypophysectomized rats were treated in vivo for 7 d with either ghrelin (320 microg/kg) or hexarelin (80 microg/kg), and their hearts were subjected in vitro to the ischemia and reperfusion procedure. Ghrelin was far less effective than hexarelin in preventing increases in left ventricular end-diastolic pressure (15% and 60% protection for ghrelin and hexarelin, respectively), coronary perfusion pressure (10% and 45% reduction), and release of creatine kinase in the heart perfusate (15% and 55% reduction). In the second experiment, normal rats were passively immunized against ghrelin for 21 d before the ischemia and reperfusion procedure. In these isolated hearts, the ischemia-reperfusion damage was not significantly increased compared with control rats. After hypophysectomy, CD36 mRNA levels significantly increased, whereas those of atrial natriuretic factor significantly decreased. We conclude that: 1) ghrelin plays a minor role in the control of heart function; and 2) hexarelin effects are mediated in part by the GHS-R and largely by interactions with the CD36.
Buscar en Google
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Daño por Reperfusión
/
Hormonas Peptídicas
/
Corazón
Límite:
Animals
Idioma:
En
Revista:
Endocrinology
Año:
2003
Tipo del documento:
Article
País de afiliación:
Italia
Pais de publicación:
Estados Unidos