Cholecystokinin innervation of the ventral striatum: a morphological and radioimmunological study.
Immunocytochemistry, radioimmunological assay after surgical cuts, anterograde degeneration and retrograde tracing of fluorescent dyes were used in order to elucidate the cholecystokinin-containing afferents to the ventral striatum (nucleus accumbens, olfactory tubercle and ventral part of the caudate-putamen). In agreement with the report by Hökfelt et al., midbrain cholecystokinin-containing cells supply the posteromedial parts of the nucleus accumbens and olfactory tubercle, as well as the subcommissural part of caudate-putamen. Brainstem cholecystokinin afferents also reach more rostral parts of the ventral striatum including the rostrolateral olfactory tubercle. The ascending cholecystokinin axons enter the medial forebrain bundle at the meso-diencephalic border and maintain a rough medial to lateral topography at the caudal diencephalon. A second major cholecystokinin pathway, with possible origin in the piriform and medial prefrontal cortices and/or the amygdala, projects to the subcommissural caudate-putamen, the olfactory tubercle, the lateral part of the nucleus accumbens and the dorsal part of the bed nucleus of stria terminalis. Finally, the rostral part of the dorsal caudate-putamen receives a substantial cholecystokinin innervation from the basolateral amygdala and possibly from the neocortex. According to radioimmunological data, the descending telencephalic cholecystokinin system accounts for about 60% of all cholecystokinin in the rostral forebrain. The combined use of morphological and biochemical methods provided evidence for a partially overlapping distribution and possible interaction between an ascending brainstem and descending telencephalic cholecystokinin fiber systems within the striatum and related rostral forebrain areas.
D000818:Animals; D001933:Brain Stem / Q000378:metabolism; D002766:Cholecystokinin / Q000032:analysis / Q000378:metabolism*; D003342:Corpus Striatum / Q000032:analysis / Q000378:metabolism*; D007124:Immunoenzyme Techniques; D008297:Male; D009434:Neural Pathways / Q000378:metabolism; D009714:Nucleus Accumbens / Q000378:metabolism; D009830:Olfactory Bulb / Q000378:metabolism; D011863:Radioimmunoassay; D051381:Rats; D013687:Telencephalon / Q000378:metabolism
D002766:Cholecystokinin