[Projections to the supraoptic and paraventricular nuclei studied in the rat by means of retrograde fluorescent tracers (fast blue, nuclear yellow)].

Afferent projections into rat supraoptic nucleus (SO) and paraventricular nucleus (PVH) were studied with two fluorescent retrograde neuronal tracers: Nuclear Yellow (NY) and Fast Blue (FB). FB labeled cells were found into paraolfactory area (ACB), basolateral amygdaloid nucleus (ABL), lateral hypothalamus (LH), ventromedial nucleus (VMH) and dorsomedial hypothalamic)nucleus (DMH), tegmental nucleus of the pons (TPO). NY labeled cells were found into posterior hypothalamus (PH), dorsal raphe nucleus (DR) and tegmental nucleus of the pons (TPO). Few double-labeled neurons were found into TPO. The finding of double labeled neurons in the TPO is of particular interest. This latter nucleus is classically connected to the cerebellum trough the olivary nucleus and can serve as liaison for transmission of messages, e.g. vestibular, regarding spacial position variations. We can conclude affirming that quite a lot of informations of diverse nature converges on the SO and PVH nuclei that by efferent pathways may regulate hypothalamic neurosecretion, thus modifying the animal's behaviour response to different external stimuli.