[Distribution in the diencephalon of the rat of retrogradely primuline-labelled dopamine-containing neurons forming spinal projections].

Distribution of primuline-labeled dopamine-containing neurons in the rat diencephalon following injection of fluorochrome into upper thoracic spinal cord was studied using a combination of catecholamine fluorescence method and retrograde cell-labeling. It was shown that only neurons of group A11 located in the dorsal hypothalamus and caudal thalamus give rise to the spinal projections. Non-catecholamine cells were also labeled in this region. Group A11 comprised 173 +/- 4 catecholamine-containing neurons. Most of them (up to 86%) were retrogradely labeled with primuline. The number of labeled dopamine-containing neurons increased in the rostro-caudal direction. Possible functional role of the dopaminergic diencephalon-spinal neuronal system is discussed.