EN
The locus coeruleus (LC) located in the pontine tegmentum, is the major noradrenergic nucleus of the brain. It gives rise to fibers innervating extensive areas within the neuraxis, among other the cerebral cortex, basal forebrain, limbic system, thalamus, brainstem autonomic nuclei, spinal cord. Throughout these projections, LC as a crucial wakefulness-promoting nucleus, is involved in neuronal circuits controlling a number of physiological functions, e.g., regulation of arousal and autonomic activity. A few data concerning the LC-cerebellar projections indicate, that LC sends same fibers to the cerebellar vermis, and small collateral projection to both the cerebral cortex and cerebellum exist as well. The aim of present study was to identify LC neurons projecting to the caudal vermal lobule, i.e. the pyramis. Following fluorescent tracer injection into the pyramis, retrogradely labelled neurons, as parent for the LC – pyramis projection, were found in defined regions of LC. The projection is bilateral with ipsilateral predominance (82% ipsiversus 18% contralateral). The LC noradrenergic connections may modulate response of the pyramis neurons and exert influence on activity of the postural muscles of upper trunk and the proximal forelimb muscles.