Transient expression of tyrosine hydroxylase in some neurons of the developing inferior colliculus of the rat.

Using immunocytochemistry, we detected tyrosine hydroxylase (TH)-containing cells in the developing inferior colliculus. These cells lacked other catecholamine-synthesizing enzymes and they occurred in newborn and immature rats up to 21 days of age. TH-positive cells of the inferior colliculus were contacted by synapses that contained pleomorphic vesicles.