Selective induction by nerve growth factor of tyrosine hydroxylase and dopamine- -hydroxylase in the rat superior cervical ganglia.

Treatment of newborn rats with 10 mug/g of nerve growth factor for 10 days enhanced not only the growth but also the differentiation of neuroblasts in superior cervical ganglia. These morphological changes were accompanied by selective induction of tyrosine hydroxylase and dopamine beta-hydroxylase (EC 1.14.2.1), whereas the total and specific activities of other enzymes involved in biosynthesis or metabolic degradation of norepinephrine rose only in proportion to the increase in volume of the sympathetic ganglia. There are remarkable similarities between this effect of nerve growth factor and the induction of trans-synaptic enzymes by increased activity of the sympathetic nervous system.