Attenuation of ANG II actions by adenovirus delivery of AT1 receptor antisense in neurons and SMC

Both central and peripheral renin-angiotensin systems (RAS) are important in the development and establishment of hypertension. Thus, introducing genes relevant to RAS into neuronal and vascular smooth muscle (VSM) cells, two major targets for angiotensin (ANG) II action, is a prerequisite in considering a gene therapy approach for the control of ANG-dependent hypertension. In this study, we explored the use of adenoviral (Ad) vector to transfer AT(1) receptor antisense cDNA (AT(1)R-AS) into neuronal and VSM cells with the anticipation of attenuation of ANG II-mediated cellular actions. Incubation of neurons and VSM cells with viral particles containing AT(1)R-AS (Ad-AT(1)R-AS) resulted in a robust expression of AT(1)R-AS in a majority (similar to 80%) of the cells. The expression was persistent for at least 28 days and was associated with decreases in the immunoreactive AT(1) receptor protein and the maximal binding for AT(1) receptor in a time-and dose-dependent manner in both cell types. ANG II stimulation of[H-3]thymidine incorporation in VSM cells and norepinephrine transporter gene expression in neuronal cells were attenuated by Ad-AT(1)R-AS infection. Uninfected cells or cells infected with adenovirus particles containing a mutant AT(1) receptor sense cDNA showed no effects on either AT(1) receptor or on attenuation of ANG II's cellular affects. These observations show for the first time, that adenovirus can be used to deliver AT(1) receptor mutant sense and antisense cDNAs into two major ANG II target tissues. This consequently influences AT(1) receptor-mediated cellular actions of ANG II.