Calcium binding protein in the basal ganglia system of a non-mammalian vertebrate: an immunohistochemical study in the reptile Caiman crocodilus.

In Caiman, calbindin D28K immunoreactivity (CaBP) was observed within many neurons of the substantia nigra (SN) but only in the caudal portion of the area ventralis of Tsai (AVT). A dense CaBP fiber plexus showing some regional inhomogeneity was observed in the dorsolateral portion of the telencephalic ventrolateral area (VLA). These results are consistent with previous reports that the SN and AVT project to the dorsolateral and medial portions of the VLA, and strongly support the theory that the caiman VLA contains cell populations homologous to those found in the mammalian corpus striatum.