In vitro determination of relative corticosteroid potency

The corticosteroid concentration required to inhibit phytohemagglutinin stimulated human lymphocyte transformation by 50% was determined for three corticosteroids. The relative potency of hydrocortisone, prednisolone and dexamethasone determined in 16 patients was 1.00, 2.43, and 24.7 respectively. This assay is proposed as an objective tool for comparison of relative corticosteroid potency in man.

Modification by imidazoles of ocular inflammatory and pressure responses

Imidazole, given intraperitoneally to rabbits, inhibited the prostaglandin E1-induced (PGE1) elevation of intraocular pressure. The maximum imidaz-le effect occurred at three to six hours after intraperitoneal infection. The prostaglandin E1-induced aqueous humor protein elevation was reduced markedly in the imidazole-pretreated rabbits. Intravenous administration of imidazole also was effective in reducing the intraocular pressure elevation produced by prostaglandin E1. Imidazole pretreatment by subconjunctival, subdermal, or topical routes had no such effect. Imidazole derivatives, 1-methylimidazole and 2-methylimidazole, given intraperitoneally, blocked the effect of PGE1 on intraocular pressure and aqueous humor protein. Imidazole pretreatment also inhibited the elevation of intraocular pressure produced by topical nitrogen mustard, 1 per cent.