Abstract
Abstract: :
Purpose: RGS5 is a potentially important modulator of signal transduction. These studies were performed to determine the regulation of regulator of G protein signaling 5 (RGS5) gene expression in chronic ocular hypertension. Methods: Unilateral ocular hypertension was created in the right eyes of 3 female cynomologus monkeys (Macaca fasicularis) in 1990 by argon laser photocoagulation of the trabecular meshwork according to the method of Sawyer et al.. Eyes from two of the three monkeys were dissected, and the iris-ciliary body was peeled away from the sclera of each eye and placed on ice. Total RNA was isolated from the iris-ciliary body immediately following ocular tissue dissection. GEM gene chip technology was used to detect differentially expressed genes in chronic ocular hypertension compared to ocular normotensive control eyes. An additional hypertensive monkey was used for the ocular tissue section preparation. In situ hybridization was performed for regional RGS5 gene expression analysis. Results: GEM gene chip analysis revealed that RGS5 mRNA was upregulated 4-6 fold in chronic ocular hypertension. In situ hybridization indicated that RGS5 mRNA is widely distributed in the monkey iris-ciliary body, and highly expressed in the ciliary muscle cells of chronic ocular hypertensive eyes. Conclusion: Considering the role of RGS5 in attenuating of receptor mediated responses, RGS5 may reflect an attempt to limit local autocoid effects. Upregulation of RGS5 in hypertensive monkey eyes suggest that RGS5 may play an important role in the regulating intraocular pressure. It follows that RGS5 may be an attractive target for screening potential anti-glaucoma drugs.
Keywords: 417 gene/expression • 444 intraocular pressure • 476 molecular biology