[Skip to Content]
[Skip to Content Landing]
October 1979

Influence of Topically Applied Prazosin on the Intraocular Pressure of Experimental Animals

Author Affiliations

From the Department of Ophthalmology, California College of Medicine, University of California, Irvine.

Arch Ophthalmol. 1979;97(10):1933-1936. doi:10.1001/archopht.1979.01020020381023

• Prazosin hydrochloride, an oral antihypertensive, is reported to inhibit phosphodiesterase and block postsynaptic α-adrenergic receptors. Intraocular pressure (IOP) in rabbits was reduced in a dose-related manner following topical ocular application of concentrations of 0.0001% to 0.1%. The ocular hypotensive response lasted six to eight hours with a maximum effect at approximately two hours. The IOP of unilaterally sympathectomized rabbits treated in both eyes with prazosin decreased more in the normal eyes than in the sympathectomized eyes. Treatment of only the unsympathectomized eyes of these rabbits elicited a similar response. Normal rabbits treated in only one eye also showed a slight response in the contralateral eye. Preliminary experiments did not support the hypothesis that these effects were due to a decrease of systemic blood pressure. No substantial ocular toxicity or pupillary changes were observed.

Brogden R, Heel R, Speight T, et al:  Prazosin: A review of its pharmacological properties and therapeutic efficacy in hypertension . Drugs 14:163-197, 1977.Article
 Pfizer forum on prazosin and hypertension . Med J Aust 2( (suppl 1) ):2-26, 1977.
Constantine J, McShane W, Scriabine A, et al:  Analysis of the hypotensive action of prazosin in hypertension , in Onesti G, Kim K, Moyer J (eds): Hypertension: Mechanisms and Management . New York, Grune & Stratton Inc, 1973, pp 429-444.
Hess HJ:  Prazosin: Biochemistry and structure—activity studies . Postgrad Med 10:9-17, 1975.
Cambridge D, Davey MJ, Massingham R:  Prazosin, a selective antagonist of post synaptic α-adrenoceptors . Br J Pharmacol 59:514-515, 1977.
Cavero I, Lefevre F, Roach A:  Differential effects of prazosin on the pre- and post-synaptic α-adrenoceptors in the rat and dog . Br J Pharmacol 61:469, 1977.
Langer S:  Presynaptic receptors and their role in the regulation of transmitter release . Br J Pharmacol 60:481-497, 1977.Article
Neufeld A, Jampol L, Sears M:  Cyclic-AMP in the aqueous humor: The effects of adrenergic agents . Exp Eye Res 14:242-250, 1972.Article
Neufeld A, Sears M:  Adenosine 3',5'-mono-phosphate analogue increases the outflow facility of the primate eye . Invest Ophthalmol 14:688-689, 1975.
Pitts NE:  Clinical evaluation of prazosin, a new anti-hypertensive agent . Postgrad Med (special issue), 1975, pp 117-127.
Langham M, Simjee A, Josephs S:  The alpha- and beta-adrenergic response to epinephrine in the rabbit eye . Exp Eye Res 15:75-84, 1973.Article
Moses R:  Intraocular pressure , in Moses R (ed): Adler's Physiology of the Eye . St Louis, CV Mosby Co, 1975, pp 179-209.