PROLONGED REDUCTION OF HIGH BLOOD-PRESSURE WITH AN IN-VIVO, NONPATHOGENIC, ADENOASSOCIATED VIRAL VECTOR DELIVERY OF AT(1)-R MESSENGER-RNA ANTISENSE

To produce a prolonged decrease in blood pressure, we have developed a nonpathogenic adeno-associated viral vector (AAV) with the antisense DNA for AT(1)-R. AAV has many advantages over other viral vectors. AAV does not stimulate inflammation or immune reaction. AAV enters nondiv iding cells and does not replicate. Therefore, it is an appropriate ch oice for gene therapy. Recombinant AAV was prepared with a cassette co ntaining a cytomegalovirus promoter and the cDNA for the AT(1) recepto r inserted in the antisense direction. The cassette was packaged in th e virion. Stable transfection of NG108-15 cells with the pAAV-AS (plas mid AAV) antisense to ATI-R produced a signif icant reduction in AT(1) receptors. A single injection of the rAAV-AS (viral vector) was made in adult spontaneously hypertensive rats, either directly in the hypot halamus (1 mu L) or in the lateral ventricles (5 mu L) The result show s that there is a significant decrease of blood pressure (approximate to 23 +/- 2 mm Hg) for up to 9 weeks after injection. Control injectio ns of mock vector produced no change in blood pressure during the same time period in age-matched controls. In young spontaneously hypertens ive rats (3 weeks), a single intracardiac injection of recombinant rAA V-AS reduced blood pressure and slowed the development of hypertension compared with controls (P < .01). The results suggest that a prolonge d reduction in high blood pressure can be achieved with AAV vectors de livering antisense to inhibit AT(1) receptors with a single administra tion.