EN
The projections from reticular formation (RF) to the pyramis (Pr; related to innervation of axial and proximal forelimb muscles) and uvula (Uv; interconnected with vestibular system) were studied using two fluorescent retrograde tracers. Bilaterally labeled RF neurons, parent for the reticulo-cerebellar projection, were found in the magno- (Lcmc) and parvocellular (Lcpc) pars of caudal lateral nucleus (n=7797), oral lateral nucleus (Lo; n=3893), and in smaller number in the lateral reticular nucleus (LR; n=1326) and gigantocellular nucleus (RGc; n=1319). The projection is seven times greater to Pr than to Uv. Connections from Lcmc to Pr originate from entire nucleus, except for the dorsolateral region, and to Uv arise from two separate neuronal populations, the ventromedial and dorsolateral, at rostral levels. While entire Lcpc supplies Pr, its rostral dorsolateral region connects Uv. The ventral LR region projects to Pr, whereas two groups of neurons in the caudal part project ipsilaterally to Uv. In Lo, neurons supplying Pr are present ventrolaterally, but these connecting Uv cluster in the dorsolateral and dorsomedial regions. Central core of the caudal RGc sends fibers exclusively to Pr. The RF projections differ regarding regions of origin and laterality, probably due to different function of Pr and Uv.