Comparative characteristic of afferent inputs to the dorsal and ventral regions of the magnocellular part of the cat red nucleus

The mosaic of topical organization of afferent inputs from some cortical, subcortical, including nucleus caudatus, brainstem and spinal cord structures to the magnocellular part of the cat red nucleus has been revealed by microiontophoretic injection of horseradish peroxidase and subsequent study of retrograde axonal transport of the enzyme. Substantial differences between afferent inputs of dorsal and ventral regions of the red nucleus as representation zones of fore- and hind-limbs in this structure were observed. It was found that while a considerable variety of afferent inputs to the ventral region of the red nucleus exists, the dorsal region receives information from only a restricted number of structures. The trajectories of retrogradely labelled fibre systems of the red nucleus have also been described.