Transient down-regulation of NMDA receptor subunit gene expression in the rat retina following NMDA-induced neurotoxicity is attenuated in the presence of the non-competitive NMDA receptor antagonist MK-801.

Excitotoxic challenge has been thought to directly target NMDA-receptive neurons to undergo cell death. Recent evidence suggests that NMDA induced cell death is a selective process and that the specificity may be determined by the subunit composition of the NMDA receptor. Using a rat retinal model, we examined the effects of NMDA induced neurotoxicity on the regulation of NMDA receptor subunit gene and protein expression levels to determine if excitotoxic challenge preferentially regulates one or more of the NMDA receptor subunits.

Up-regulation of novel intermediate filament proteins in primary fiber cells: an indicator of all vertebrate lens fiber differentiation?

The early embryonic development and expression patterns of the eye lens specific cytoskeletal proteins, CP49 and CP95, were determined for the chick and were found to be similar in both human and mouse. These proteins, as well as their homologs in other species, are obligate polymerization partners which form unique filamentous structures termed "beaded filaments." CP49 and CP95 appeared as protein products after 3 days of embryonic development in the chick during the elongation of primary fiber cells.

NMDA receptor subunit gene expression in the rat brain: a quantitative analysis of endogenous mRNA levels of NR1Com, NR2A, NR2B, NR2C, NR2D and NR3A.

Electrophysiological recordings have shown NMDA receptors to be heterogenous structures capable of responding to selected antagonists and agonists in multiple ways. This diversity in functional response has led investigators to conclude that these channels are comprised of unique combinations of receptor subunits which determine a cell's functional NMDA-signature [H. Meguro, H.

Immunocytochemical localization of the NMDA-R2A receptor subunit in the cat retina.

Immunocytochemical studies were performed to determine the distribution and cellular localization of the NMDA-R2A receptor subunit (R2A) in the cat retina. R2A-immunoreactivity (R2A-IR) was noted in all layers of the retina, with specific localizations in the outer segments of red/green and blue cone photoreceptors, B-type horizontal cells, several types of amacrine cells, Müller cells and the majority of cells in the ganglion cell layer. In the inner nuclear layer, 48% of all cells residing in the amacrine cell layer were R2A-IR including a cell resembling the GABAergic A17 amacrine cell.

Early TIMP gene expression after corneal infection with Pseudomonas aeruginosa.

Purpose: To evaluate the expression of tissue inhibitor of metalloproteinases (TIMP) mRNA in corneal tissues before and at early time points (6 and 12 hours and 1, 3, and 5 days) after corneal infection with Pseudomonas aeruginosa.

Methods: Ribonuclease protection assays were used to detect and quantitate TIMP mRNA expression in uninfected (wounded and unwounded) and in wounded corneas inoculated with P. aeruginosa.