At postnatal day 35 (P35), rd10 mice given daily subcutaneous injections of 40 mg/kg of Metipranolol has reduction in markers of nitrosative stress, fewer TUNEL-positive cells, increased outer nuclear layer thickness, and substantially more staining for rhodopsin. At P50, Metipranolol-treated rd10 mice has decreased 3-nitrotyrosine staining in the retina, increased immunostaining for cone arrestin, a marker for cone photoreceptors, and significantly higher scotopic and photopic b-wave amplitudes at the highest stimulus intensity. At P65, cone density is significantly higher in Metipranolol-treated versus vehicle-injected rd10 mice[1].