[Origin of extraorthosympathetic nerve fibers innervating the epiphysis of the rat (study of retrograde transport of horseradish peroxidase)].

After horseradish peroxidase was injected into the rat pineal gland, isolated and rare labelled perikarya appeared in the central nervous system, particularly in the habenula, colliculi, amygdala, paraventricular and suprachiasmatic nuclei, preoptic area and olfactive centers. This indicates that the innervation of the pineal gland is not only orthosympathetic but that some stimuli can be directly transmitted from the brain to the pineal stalk.