Improvement of ocular blood flow with dopamine antagonists on ocular-hypertensive rabbit eyes

The eyedrops of the ocular-hypotensive dopamine antagonists, trifluperidol, moperone, lenperone, and spiperone, were instilled into an ocular-hypertensive rabbit eye. The blood flows in the choroid, retina, iris root-ciliary body, and iris were measured with colored microspheres at various time periods. It was found that all these dopamine antagonists, at a concentration of 0.5%, increased the blood flow in all eye tissues. Dopamine, at a concentration of 3%, produced a biphasic action by decreasing the blood flow initially at 30 min, then increasing it at 120 min and thereafter. But 1.5% dopamine produced a monophasic action which increased the blood flow after 180 min. Since dopamine antagonists are not cholinergics or adrenolytics, they are not supposed to produce the side effects induced by pilocarpine or timolol. It is hoped that they can become satisfactory drugs for glaucoma and ocular hypertension.