Other groups have shown that Rap1 activation in vivo by methods including 8CPT-cAMP treatment can reduce microvascular permeability [35], [54], protect against renal failure in ischemia-reperfusion injury [55], and inhibit lung vascular leak in ventilator-induced lung injury [12]; our findings suggest Rap1 activation may also be a valid pharmacological strategy to strengthen RPE barrier properties and prevent choroidal neovascularization that occurs in AMD. Here, RAP1A is linked to age-related macular degeneration.