The present invention provides a method for delivering a pharmaceutical polypeptide to the interior of a cardiac cell of a vertebrate in vivo, comprising the step of introducing a preparation comprising a pharmaceutically acceptable injectable carrier and naked polynucleotide operatively coding for the polypeptide into the interstitial space of the heart, whereby the naked polynucleotide is taken up into the interior of the cell and has a pharmacological effect on the vertebrate such as inducing vascular growth. In a preferred embodiment wherein the polynucleotide encodes polypeptide immunologically foreign to the vertebrate, the delivery method preferably comprises delivering an immunosuppressive agent to the vertebrate to limit immune responses directed to the polypeptide.