Activation of ATP receptor increases the cytosolic Ca(2+) concentration in ventral tegmental area neurons of rat brain.

ATP increased the cytosolic Ca(2+) concentration ([Ca](i)) in neurons of ventral tegmental area acutely dissociated from rat brain. The ATP response was dependent on external Ca(2+) and Na(+), and was blocked by voltage-dependent Ca(2+) channel blockers. The results suggest that the ATP-induced depolarization increases Ca(2+) influx via voltage-gated Ca(2+) channels resulting in the increase in [Ca](i).