Selective serotonin inhibitors and their perspectives in ophthalmology

Serotonin plays an important role in maintaining homeostasis due to a broad spectrum of receptors localized in nearly every part of the body, i.e., central nervous system, vegetative ganglia, cardiac and lung reflexogenic zone, smooth muscles, internal organs and microcirculatory bloodstream, ocular tissues and optic tract. Serotonin levels can be altered by serotonin receptor blockade. Dusopharm (naftidrofuryl), a drug with complex mechanism of action, inhibits 5-HT2 receptors. Selective inhibiting of 5-HT2 receptors of vascular endothelial and smooth muscle cells decreases vasoconstrictor effects of serotonin that releases from atherosclerosisand hypoxia-damaged vascular endothelium and prevents thrombocyte aggregation. In addition, naftidrofuryl is the antagonist of vasoconstrictor action of endothelin-1 expressed by vascular endothelium. Experiments with isolated rabbit smooth myocytes demonstrate that naftidrofuryl prevents endothelin-1 binding with endothelial serotonin receptors and smooth myocyte contraction. Naftidrofuryl improves blood flow owing to its effect on blood rheological properties (increases erythrocyte deformability and decreases their aggregation). This paper reviews the studies of Dusopharm in patients with intermittent claudication, post-insult conditions, diabetic retinopathy, age-related macular degeneration (AMD), glaucoma, and central retinal vein and its branches occlusion. These data allow to include Dusopharm in the complex therapy of central retinal vein and its branches occlusion, diabetic retinopathy, age-related macular degeneration (AMD), glaucoma, peripheral retinal degeneration, and retinal detachment to improve and stabilize visual functions and microcirculation.