Mechanisms of phagocytosis are complex and incompletely understood. The retinal pigment epithelium provides an ideal system to study the specific aspects of phagocytosis since an important function of this cell is the ingestion of packets of membranous discs that are normally discarded at the apical ends of rod and cone cells during outer segment renewal. Here we provide evidence that rod outer...

Sonic hedgehog is involved in eye field separation along the proximodistal axis. We show that Hh signalling continues to be important in defining aspects of the proximodistal axis as the optic vesicle and optic cup mature. We show that two other Hedgehog proteins, Banded hedgehog and Cephalic hedgehog, related to the mouse Indian hedgehog and Desert hedgehog, respectively, are strongly expresse...

Ornithine ketoacid aminotransferase in bovine ocular tissues was studied biochemically. The retinal pigment epithelium, ciliary body, iris, and neuroretina showed high specific activity. The cornea and choroid revealed a lower activity. Aqueous humor, lens, vitreous body, and sclera showed no activity. The pH optima of the enzyme in the retinal pigment epithelium and ciliary body were near 8.0.

PURPOSE Pigment epithelium derived factor (PEDF) is a secreted protein with demonstrated anti-angiogenic properties, and with potential application for the treatment of neovascular disease. Delivery of pigment epithelium derived factor to the retina via virus mediated gene transfer has been shown to inhibit neovascularization in a number of experimental models. While pigment epithelium derived ...

The BB rat spontaneously develops a diabetic state that closely resembles human type I diabetes. The authors studied the pathologic changes of the retina and retinal pigment epithelium of four normal and nine diabetic BB rats using (1) light and electron microscopy with the horseradish peroxidase tracer technique, and (2) trypsin digest preparations of the retinal vessels. They observed a retin...

OBJECTIVE To investigate the clinicopathological correlation of parapapillary atrophy. MATERIALS AND METHODS The study included 16 eyes of rhesus monkeys (Macaca mulatta) - 4 eyes with experimental glaucoma, 11 eyes after experimental temporary occlusion of the central retinal artery, and 1 normal eye. On histological sections, we measured zones with different histological characteristics.On ...

A 47-year-old Japanese man had a progressive degeneration of the retina and choroid along the retinal veins associated with uveitis of two years' duration. The lesion was characteristic of paravenous retinochoroidal atrophy: a contiguous atrophy of the retinal pigment epithelium and choroid of one-half to one disc diameter in size was present along most of the veins from the posterior pole to t...

retinal pigment epithelium is responsible for maintaining the structural integrity of the retina by an efficient defense against free radicals, photo-oxidative exposure and light energy. for this purpose the main rpe line of defense is melanosomes. melanin content of retinal pigment epithelium cells in adults and neonates reveals remarkable variations. in the current study we compared melanogen...

A hole was detected in the epithelium of a retinal pigment epithelium (RPE) detachment in two patients. Leakage through the hole led to an elevation of the overlying neurosensory retina in each case. The resulting vision was 20/70 in one eye and 20/30 in the other. The defects in the RPE occurred in a setting different from that usually seen with tears in the pigment epithelium and had a differ...