Characterization of a galactosyltransferase in purified bovine rod outer segments.

Purified bovine rod outer segments (ROS) were used to study the transfer of labeled galactose from UDP-[3H]galactose to endogenous ROS glycoproteins, exogenous glycoproteins and N-acetylglucosamine (GlcNAc). The ROS reaction was also compared with that of the retinal microsomal fraction and milk galactosyltransferase. The results indicate that the ROS reaction was enhanced by exposure to light.

Effect of light on the transfer of sugars from sugar nucleotides to rod outer segment membranes of control and dystrophic rats.

The transfer of N-acetyl-D-glucosamine (GlcNAc), D-mannose (Man), D-galactose (Gal) and L-fucose (Fuc) from their nucleotide complexes to isolated rod outer segment (ROS) membranes obtained from dark-adapted 21 +/- 2 days old dystrophic (RCS) and control (RCS-rdy+) rat retinas, was studied under light or dark conditions of incubation. It was found that all of these sugars were transferred to ROS membranes in the dark. Under these conditions there was significantly less (p less than 0.

The rat electroretinogram in combined zinc and vitamin A deficiency.

To assess the relative importance and interdependence of zinc and vitamin A in retinal function, a group of 36 male Wistar rats were raised in dim illumination and deprived of both zinc and vitamin A (Z-A-) for 90 days (Phase I) until they lost weight and showed signs of both vitamin A and zinc deficiency. Scotopic electroretinograms (ERGs) showed an average 1.5 log unit elevation in light intensity needed to elicit a 200 microV b-wave (criterion intensity) as compared to a control-pair-fed group of rats.

Ocular distribution of methyprylon after intravenous injection and transfer of the drug to recipient eye via corneal graft.

The purpose of the study was to determine chronologically the ocular distribution of methyprylon (Noludar) after a single intravenous injection (45 mg/kg) to rabbits, if the drug can be transferred from a donor treated with the drug to the recipient's eye via an allogeneic corneal graft, and the effect of methyprylon on corneal cell growth and protein synthesis. Gas chromatographic techniques showed that the drug was present in all the tissues and fluids of the eye from 0.5 to 18 hours after the injection.