The role of the endothelin system in the pathogenesis of eye diseases

Abstract

The endothelin system (ES) plays a complex role in the pathogenesis of various eye diseases as a local regulator of vascular tone as well as many other physiological processes. Components of ES - endothelins and their receptors - can be found nearly in all cellular structures of the eye, their concentration increases in the presence of many eye diseases. In glaucoma, ES is involved in the mechanisms of eye hypertension by influencing the secretion and outflow of aqueous humor. The increase of endothelin level leads to the decrease of perfusion pressure, hypoxia, astrocyte proliferation, increase of density and rigidity of lamina cribrosa, apoptosis of neural cells, and has a profibrogenic effect. In retinal pathology, increase of endothelins disturbs autoregulation of retinal blood vessels changing the neurovascular interactions, breaks intercellular contacts in the retina, promotes neoangiogenesis. In diabetic retinopathy, ES contributes to the development of microangiopathy and proliferative vitreoretinopathy. The review discusses the possibility of correcting ES activity in the eye with medications by influencing its synthesis, cleavage and receptor binding.