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 mug/kg) or hexarelin (80 mug/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.
|Citazione:||Torsello, A., Bresciani, E., Rossoni, G., Avallone, R., Tulipano, G., Cocchi, D., et al. (2003). Ghrelin plays a minor role in the physiological control of cardiac function in the rat. ENDOCRINOLOGY, 144(5), 1787-1792.|
|Tipo:||Articolo in rivista - Articolo scientifico|
|Carattere della pubblicazione:||Scientifica|
|Titolo:||Ghrelin plays a minor role in the physiological control of cardiac function in the rat|
|Autori:||Torsello, A; Bresciani, E; Rossoni, G; Avallone, R; Tulipano, G; Cocchi, D; Bulgarelli, I; Deghenghi, R; Berti, F; Locatelli, V|
|Data di pubblicazione:||mag-2003|
|Appare nelle tipologie:||01 - Articolo su rivista|