EFFECTS OF MTX AND BN52021 ON PAF-INDUCED CHEMOTAXIS OF PMNS AND INTRAEPIDERMAL ACCUMULATION OF INFLAMMATORY CELLS IN GUINEA-PIGS

Objective. To investigate the effets of methotrexate (MTX) and platele t activating factor (PAF) antagonist ginkgolide B (BN52021) on PAF ind uced chemotaxis of neutrophils. Materials and Methods. All guinea Digs were randomly divided into 12 groups. They were given different dosag es of MTX and BN52021 by intra-abdominal injections. The random and ch emotactic migration of polymorphonuclear leukocytes (PMNs) were measur ed by the agarose method. The backs of all guinea Digs were given intr adermal injections of PAF and the numbers of the infiltration of infla mmatory cells into the skin were determined. Results. MTX inhibited ra ndom migration and chemotactic migration of PMNs to PAF, LTB4 and PAF- induced intraepidermal accumulation of inflammatory cells in dose- and time-dependent fashion. BN52021 specially inhibited PAF-induced chemo taxis of PMNs and intraepidermal accumulation of inflammatory cells, b ut did not inhibit PMNs random migration and LTB4-induced chemotaxis o f PMNs. Conclusions. The inhibition of PMNs activities may be part of the mechanism of MTX therapy for psoriasis; BN52021 is a selective inh ibitor of PAF-induced chemotaxis of PMNs, and therefore can be useful in the treatment of some inflammatory dermatoses such as psoriasis.