Reversal effect of isaxonine on modifications of rat polymorphonuclear migration by colchicine

Using a modified Boyden chamber, random migration and chemotaxis of rat polymorphonuclear leucocytes (PMN) were assessed after incubation in vitro in a solution of colchicine (1.5 X 10(-5) M). The results obtained were compared to random migration or chemotaxis of the same cellular pool treated in vitro or in vivo by N-isopropyl-amino-2-pyrimidine phosphate (isaxonine 4.10(-5) M or 75 and 150 mg/kg respectively). Isaxonine partially inhibited the effect of colchicine on PMN chemotaxis while random migration remained unaffected. Isaxonine might partially inhibit the noxious effect of colchicine on microtubule disruption by a direct effect (polymerization of free tubulin) and/or indirect effect (impairment of disorganizing activity) on PMN microtubules.