Therapeutic potential of nitric oxide modulation in ocular diseases.

Nitric oxide (NO) is an organic gas ubiquitously synthesized in mammalian tissues by NO synthase (NOS). Over the past 20 years, remarkable progress has been made in explaining the mechanism/s of NO and its functions in different biological systems. NO is produced as metabolic endproduct in specific cell life phases, and may act as a atypical neuronal messenger. NO is an important regulator of homeostatic processes in the eye and changes in its synthesis could lead to a variety of eye diseases such as glaucoma, retinal degeneration and uveitis. Both overexpression and underexpression of NO could contribute to pathological conditions in the eye. Many works have highlighted the role of NO in a wide range of ocular diseases and recent studies from our laboratory and others have shown that a suppressive action of inducible NOS-derived NO production lowers the intraocular pressure. Indeed, from a clinical perspective, a precise regulation of NO may lead to new therapeutic options likely safer and more efficacious than currently available treatments for various sight-threatening eye diseases.