Bradykinin activates tyrosine hydroxylase in rat pheochromocytoma PC-12 cells.

Tyrosine hydroxylase is activated in PC-12 cells by bradykinin in a concentration-dependent manner with maximal stimulation occurring at 1 microM. This stimulatory effect occurs within 15 s and is maximal at 5 min. This stimulation is due to an increase in the affinity of tyrosine hydroxylase for its pterin cofactor, and can be blocked by a specific bradykinin receptor antagonist. These data indicate that bradykinin can regulate the activity of tyrosine hydroxylase in PC-12 cells.