[The effect of vasoactive intestinal polypeptide (VIP) on ocular inflammation in rabbit ocular tissue]

Intravitreous injection of vasoactive intestinal polypeptide (VIP) induced ocular inflammation in albino rabbits. Protein amounts and cell numbers in aqueous humor were measured. The effect of VIP on the release of cyclic AMP (cAMP) and prostaglandin E2 (PGE2) from the isolated albino rabbit irides was investigated. Mydriatic response was obtained by intravitreous injection of 0.5 microgram or less VIP. 5 microgram or more of VIP induced miosis and breakdown of the blood aqueous barrier. Intravitreous injection of VIP induced on increase of cAMP in the aqueous humor dose-dependently and a slight increase of PGE2. VIP induced a dose-dependent increase of cAMP release and slightly inhibit PGE2 release from isolated irides. In this study, a large quantity of VIP was injected intravitreously induced breakdown of the blood aqueous barrier. The effect of VIP on isolated irides was to activate the release of cAMP and to inhibit that of PGE2.