Antiinflammatory actions of methyl- and phenyl-3-methoxy-4-hydroxy styryl ketones.

Methyl- and phenyl-3-methoxy-4-hydroxy styryl ketones (MHSK and PHSK, resp.) upon oral administration displayed marked antiinflammatory activity in a variety of acute tests viz. carrageenan, histamine, 5-hydroxytryptamine, dextran, bradykinin and prostaglandin (PG) induced oedema in rats and carrageenan evoked swelling in mice; the activity was not altered by adrenalectomy. In subacute test of formaldehyde arthritis, they showed significant reduction in paw swelling but were less effective in granuloma tests. In chronic tests, they produced marked antiarthritic effect both in developing and established adjuvant arthritis. The compounds prevented the inflammation induced increase in serum transaminase levels and leucocyte counts. They inhibited the passive cutaneous anaphylaxis and produced reduction in ADP induced platelet aggregation. The compounds showed weaker antipyretic activity than acetylsalicylic acid in pyretic animals. MHSK showed analgesic activity using the tail clip method and antagonised acetic acid induced writhing syndrome. The compounds lacked any local anaesthetic activity. The low ulcerogenic potential of these compounds in animal models may be related to their relative inability to inhibit PG synthetase.