The Action of Angiotensin on Intraocular Pressure

Introduction  Current findings strongly suggest that intraocular pressure (IOP) of the cat eye is dependent upon venous pressure^2-5,7-10 which in turn can be regulated by changes in resistance of the iris artery and its radial branches.⁶Acetazolamide has been demonstrated to lower intraocular pressure, at least in part, by its ability to produce a fall in venous pressure^2,3 through its constrictive effect of the iris blood vessels.⁶ Many other agents, even though of diverse origin and activity, which have been shown capable of producing a lowering of IOP in patients with glaucoma, have all been found to have the common effect of producing an increase in resistance in the iris artery.⁹Recently dilutions of serum were also shown capable of producing increases in resistance of the iris artery. Almost all of this serum vasoconstrictor activity could be ascribed to a substance which had many of