Prostaglandin and nerve-mediated response of the rabbit eye to argon laser irradiation of the iris.

Irradiation of the pigmented rabbit iris with a moderately low dose of argon laser light (5 applications of 750 mW, 500 micron, 0.5 sec) caused an immediate ocular response consisting of miosis, a rise of intra-ocular pressure and is accompanied by a disruption of the blood-aqueous barrier. Prostaglandin-like material was present in the aqueous humour withdrawn 60 minutes after irradiation. Prior treatment with indomethacin intravenously (20 mg/kg) or benoxinate topically (Novesine; 0.4%) greatly reduced the response and the combined use of the two drugs virtually abolished the ocular changes.