A chemically induced experimental ocular hypertension for evaluating drug effects in albino rabbits.

Abstract

A test model is described for production of experimental ocular hypertension in albino rabbits. The procedure employs applanation tonometry for intraocular pressure (IOP) measurement; is simple in design and requires little time to perform. Eight pharmacologic classes of drugs were evaluated using this procedure. Good correlation is described between drugs topically effective in clinical treatment of glaucoma and those lowering IOP in this test system. The described method was most sensitive for the adrenergic stimulants of both α and β variety. Physostigmine (cholinesterase inhibitor) effectively lowered IOP as did the direct-acting cholinergic stimulant carbachol. A concentration-response relationship with pilocarpine, however, was not observed. Ganglionic blocking agents effectively lowered IOP and confirm the involvement of a neuroreflex mechanism involved in production of “irritation-induced” hypertension. Adrenergic blocking agents, muscarinic cholinergic blocking agents, and local anesthetics were ineffective ocular hypotensive agents in this test model.