OBJECTIVE To assess the electrophysiologic, histologic, and biochemical features of an animal model of Smith-Lemli-Opitz syndrome (SLOS). METHODS Sprague-Dawley rats were treated with AY9944, a selective inhibitor of 3beta-hydroxysterol-Delta(7)-reductase (the affected enzyme in SLOS). Dark- and light-adapted electroretinograms were obtained from treated and control animals. From each animal,...

PURPOSE The pathophysiology of vision loss in persons with diabetic retinopathy (DR) is complex and incompletely defined. We hypothesized that retinal pigment epithelium (RPE) and rod and cone photoreceptor dysfunction, as measured by dark adaptometry, would increase with severity of DR, and that pan-retinal photocoagulation (PRP) would exacerbate this dysfunction. METHODS Dark adaptation (DA...

In the mouse model of unilateral laser-induced ocular hypertension (OHT) the microglia in both the treated and the normotensive untreated contralateral eye have morphological signs of activation and up-regulation of MHC-II expression in comparison with naïve. In the brain, rod-like microglia align to less-injured neurons in an effort to limit damage. We investigate whether: i) microglial activa...

PURPOSE To test alternative hypotheses concerning the mechanisms of rod degeneration in retinitis pigmentosa (RP). METHODS Full-field rod electroretinograms and rod visual fields were measured for 15 patients with RP and a normal control group. The rod a-wave was fitted with a computational model based on known transduction biochemistry. The values of td (the initial delay), S (a sensitivity ...