Monosodium urate crystals stimulate phospholipase A sub(2) enzyme activities and the synthesis of a phospholipase A sub(2)-activating protein

Eicosanoids are important mediators of the inflammatory response to monosodium urate crystals (MSUC) that results in gout. Phospholipase enzymes cleave fatty acids from membrane phospholipids, and this is thought to be the rate-limiting step in eciosanoid production. To understand better the mechanism of eciosanoid production in this disease, we stimulated human peripheral blood neutrophils and monocytes with MSUC and measured phospholipase enzyme activities. The findings suggest that phospholipase A sub(2) activation in response to MSUC requires an intact microtubule structure, and that phospholipase A sub(2) and PLAP may be important modulators of at least a portion of the gouty inflammatory response.