Modulation of ventricular function through gene transfer in vivo

Abstract
We used a catheter-based technique to achieve generalized cardiac gene transfer in vivo and to alter cardiac function by overexpressing phospholamban (PL) which regulates the activity of the sarcoplasmic reticulum Ca2+ ATPase (SERCA2a). By using this approach, rat hearts were transduced in vivo with 5 × 109 pfu of recombinant adenoviral vectors carrying cDNA for either PL, β-galactosidase (β-gal), or modified green fluorescent protein (EGFP). Western blot analysis of ventricles obtained from rats transduced by Ad.PL showed a 2.8-fold increase in PL compared with hearts transduced by Ad.βgal. Two days after infection, rat hearts transduced with Ad.PL had lower peak left ventricular pressure (58.3 ± 12.9 mmHg, n = 8) compared with uninfected hearts (92.5 ± 3.5 mmHg, n = 6) or hearts infected with Ad.βgal (92.6 ± 5.9 mmHg, n = 6). Both peak rate of pressure rise and pressure fall (+3, 210 ± 298 mmHg/s, −2, 117 ± 178 mmHg/s, n = 8) were decreased in hearts overexpressing PL compared with uninfected hearts (+5, 225 ± 136 mmHg/s, −3, 805 ± 97 mmHg/s, n = 6) or hearts infected with Ad.βgal (+5, 108 ± 167 mmHg/s, −3, 765 ± 121 mmHg/s, n = 6). The time constant of left ventricular relaxation increased significantly in hearts overexpressing PL (33.4 ± 3.2 ms, n = 8) compared with uninfected hearts (18.5 ± 1.0 ms, n = 6) or hearts infected with Ad.βgal (20.8 ± 2.1 ms, n = 6). These differences in ventricular function were maintained 7 days after infection. These studies open the prospect of using somatic gene transfer to modulate overall cardiac function in vivo for either experimental or therapeutic applications.

This publication has 26 references indexed in Scilit: