[Leukotrienes and monohydroxy fatty acids: controversial role in the pathogenesis of psoriasis]

The pros and cons concerning the involvement of arachidonic acid metabolism in the pathogenesis of psoriasis are presented. The isolation of arachidonic acid metabolites from psoriatic lesions, their extraordinary biological activity, and the therapeutic efficiency in psoriasis of inhibitors of arachidonic acid metabolism all argue in favor of leukotrienes and monohydroxy fatty acids playing an important role in the development of psoriasis plaques. On the other hand, the lack of specificity of the biochemical findings, the failure to reproduce psoriatic lesions by arachidonic acid metabolites, and the therapeutic activity of drugs that have no effect on arachidonic acid metabolism show that the role of arachidonic acid metabolism in the pathogenesis of psoriasis is still controversial. The availability of selective inhibitors of arachidonic acid-metabolizing enzymes for clinical testing is a prerequisite before pathophysiological conclusions can be made, as the present status of knowledge makes any conclusions premature.