抄録
The superior salivatory (SS) nucleus, the primary parasympathetic center for salivary secretion, is located in the lateral reticular formation of the medulla oblongata. Many neuroanatomical studies suggest that the neurons innervating SS neurons are distributed in the forebrain and brainstem. Our electrophysiological studies showed that most SS neurons receive GABAergic and glycynergic inhibitory inputs from higher and lower centers. In the present study, we examined distribution of GABAergic and glycinergic neurons innervating SS neurons immunohistochemically. The neurons innervating SS neurons were labeled by the injection of retrograde tracer FluoroGold into SS nucleus. To examine the distribution of GABAergic and glycinergic somata, double immunostaining was performed using anti-GABA and anti-glycine antibodies, and was observed under the fluorescence microscope. GABA-immunoreactive neurons were mainly observed in higher centers including the lateral hypothalamic area, paraventricular nucleus of hypothalamus, central nucleus of amygdala, bed nucleus of stria terminalis and preoptic area. Glycine-immunoreactive neurons were observed mainly in lower centers including the parabrachial nucleus, sensory trigeminal nucleus, nucleus of solitary tract. These findings imply that these higher and lower centers are involved in the inhibitory salivary control. [J Physiol Sci. 2007;57 Suppl:S236]
