Vanadium as a factor that disturbs phosphorus metabolism in nervous tissue

Vanadium and its derivatives are the well-known environmental pollutants. We obtained that ammonium vanadate suppressed the alkaline (AlP) and acid (AcP) phosphatases activity in the variety of tissues. Vanadate inhibited the enzymes that take part in phosphoryl transfer reactions. Successive concentration-dependent decrease in AlP and AcP activities by vanadate (0.1 mM-1 mM) has been obtained in rat nervous tissue. Moreover, the observed reduction in the sensitivity of the enzymes to vanadate ions becomes more pronounced at the transition from higher and relatively young regions of nervous system to its more ancient parts. Phosphoprotein phosphatase (PP) activity has also been inhibited in various structures of brain tissue; in spinal cord, however, vanadate in comparatively low concentrations (10 microM) caused a steep rise in the enzyme activity. Only at high concentration (1 mM) vanadate exert the effect of moderate inhibition. The possibility of the existence of phylogenetically different molecular forms of nervous tissue PPs differed by their sensitivity to vanadate was supported in our comparative examination.