The transgene consists of the human beta-2 adrenergic receptor (ADRB2), an SV40 intron/polyA sequence, and the murine myosin, heavy polypeptide 6, cardiac muscle, alpha (Myh6) promoter which directs cardiac-specific overexpression of ADRB2. Transgene expression is detected in cardiac myocytes at levels 200 times greater than in human cardiac tissue.