Increasing proportions of tyrosine hydroxylase-immunoreactive interneurons colocalize with choline acetyltransferase or vasoactive intestinal peptide in the developing rat cerebral cortex.

Cortical interneurons are critical for information processing, and their dysfunction has been implicated in neurological disorders. One subset of this diverse cell population expresses tyrosine hydroxylase (TH) during postnatal rat development. Cortical TH-immunoreactive neurons appear at postnatal day (P) 16.