Abstract

Pentoxifylline (PTX) has been recently reported to stimulate PMN chemotaxis under dense agarose. The present study was designed to characterize the effect of PTX on actin polymerization before and after stimulation by the chemotactic factor f-MLP- We used two different methods to determine the proportion of actin in the filamentous form: SDS-polyacrylamide gel electrophoresis to study the Triton X-100 insoluble cytoskeleton, and flow cytometry using fluorescent Rhodamine-Phalloidin to study actin conformation. PTX (10(-3) M) did not affect the amount of F-actin (polymerized G-actin) incorporated into the cytoskeleton, but reduced total F-actin in a dose-dependent manner, at all concentrations of f-MLP used. Moreover, this inhibitory effect appeared more clearly in PMN with the higher activation ratios. Thus F-actin is only partially incorporated into the cytoskeleton, and PTX-induced reduction of non-incorporated actin may reduce the stiffness of activated PMN. This could explain the increased chemotaxis of PMN across the small holes of dense agarose.

Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call