Ontogeny of cholecystokinin receptors in the human striatum

The distribution of cholecystokinin binding sites was studied by receptor autoradiography in the human striatum at midgestation, birth and adulthood. In the adult, cholecystokinin receptors are inhomogeneously distributed with patches of reduced labeling. In the caudate nucleus but not in the putamen these patches match the striosomal organization as revealed by acetylcholinesterase staining. At midgestation, patches of high density of cholecystokinin receptors are in register with the dopamine D1 receptor-enriched striosomes. At birth, this striosomal organization has already evolved into the adult pattern of higher matrix level in contrast to the striosomal pattern of acetylcholinesterase staining.