MARKED ENHANCEMENT IN MYOCARDIAL-FUNCTION RESULTING FROM OVEREXPRESSION OF A HUMAN BETA-ADRENERGIC-RECEPTOR GENE

Transgenic mice with intense cardiac expression of a human beta-adrene rgic receptor gene were engineered and shown to display marked improve ments in baseline myocardial and left ventricular function. Heart/body weight ratios and histologic appearance were not found to be signific antly altered, suggesting that receptor gene expression did not induce pathologic changes. Given the substantial reduction in beta-adrenergi c receptor density and resultant reduction in inotropic responsiveness observed in chronic heart failure, these findings represent a novel a pproach for increasing myocardial function with important clinical imp lications.