Abstract
The renin-angiotensin system (RAS), that is known for its role in the regulation of blood pressure as well as in fluid and electrolyte homeostasis, comprises dozens of angiotensin peptides and peptidases and at least six receptors. Six central components constitute the two main axes of the RAS cascade. Angiotensin (1-7), an angiotensin converting enzyme 2 and Mas receptor axis (ACE2-Ang(1-7)-MasR) counterbalances the harmful effects of the angiotensin II, angiotensin converting enzyme 1 and angiotensin II type 1 receptor axis (ACE1-AngII-AT1R) Whereas systemic RAS is an important factor in blood pressure regulation, tissue-specific regulatory system, responsible for long term regional changes, that has been found in various organs. In other words, RAS is not only endocrine but also complicated autocrine system. The human eye has its own intraocular RAS that is present e.g. in the structures involved in aqueous humor dynamics. Local RAS may thus be a target in the development of new anti-glaucomatous drugs. In this review, we first describe the systemic RAS cascade and then the local ocular RAS especially in the anterior part of the eye.
Highlights
Glaucoma, known for its destructive effects on the optic nerve axons and retinal ganglion cells, is one of the leading causes of blindness worldwide
While the pathological mechanisms at molecular level are not yet well understood, local ocular renin-angiotensin system (RAS) seems to have a role in ocular pathology and it has been associated to glaucoma and other eye disorders such as diabetic retinopathy (DR), age-related macular degeneration (AMD) and retinopathy of prematurity (ROP) [22, 25]
Over 40 years later, more components of the RAS cascade were identified, one being the angiotensin peptide, first named as angiotonin, that Braun-Menéndez and Page reported to be formed from angiotensinogen by renin, an enzyme originated in the kidney [28 - 30]. 1970 was an important year in the RAS research as its role in blood pressure (BP) and fluid balance regulator was understood which led to the development of the first antihypertensive medications such as captopril that blocks the formation of Ang II by inhibiting ACE1 [20, 28]
Summary
Known for its destructive effects on the optic nerve axons and retinal ganglion cells, is one of the leading causes of blindness worldwide. In addition to the classical RAS that regulates blood pressure (BP), fluid volume as well as electrolyte balance and is involved in inflammation, local tissue-specific RA-systems have been described in numerous organs including the human eye [20 - 24]. 1970 was an important year in the RAS research as its role in BP and fluid balance regulator was understood which led to the development of the first antihypertensive medications such as captopril that blocks the formation of Ang II by inhibiting ACE1 [20, 28].
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
