Non-steroidal anti-inflammatories--XII. Mode of action of anti-inflammatory methane sulfonanilides.

The influence of anti-inflammatory methane sulfonanilides on the arachidonic acid metabolism in ram seminal vesicle homogenate depends on the pK3 of the individual substance: more acidic compounds suppress, less acidic compounds stimulate PG synthesis and enhance the PGH2/PGG2 ratio. As oxygen radicals are liberated during the conversion of PGG2 to PGH2 it is suggested that the less acidic methane sulfonanilides are scavengers of the (pro-inflammatory) oxygen radicals.