This invention relates to compositions and methods for treatment of vascular conditions. The invention provides arginine polymers and arginine homopolymers for the treatment and/or prevention of glaucoma, pulmonary hypertension, asthma, chronic obstructive pulmonary disease, erectile dysfunction, Raynaud's syndrome, heparin overdose, vulvodynia, and wound healing. The invention also provides arginine polymers and arginine homopolymers for use in organ perfusate and preservation solutions.