| Abstract: | The effects of diisopropylphosphorofluoridate (DFP) and other organophosphorus compounds on the locomotion of rabbit polymorphonuclear leucocytes have been investigated in vitro using time-lapse cinémicrography. Both phosphorylating and non-phosphorylating compounds were observed to inhibit cell locomotion, not only increasing the proportion of stationary cells, but also decreasing the velocity of those cells whose movement continued. This inhibition of locomotion occurred over the same concentration range of organophosphorus compound which was previously found to enhance the effect of leucocidin on the leucocyte. Although the inhibitory effects of low concentrations of organophosphorus compounds were partly reversible, higher concentrations produced effects which continued to increase even after the cells had been returned to normal medium. It is suggested that the supposed effect of organophosphorus compounds on chemotaxis may actually be due to the inhibition of locomotion per se, probably through the detergent properties of these compounds rather than their properties as enzyme inhibitors. |
