Innervation of hypothalamic and limbic areas by the cholinergic, the GABA-ergic and the catecholaminergic nerve...

By measuring activities of enzymes involved in synthesis of acetylcholine, gamma-aminobutyric acid (GABA), dopamine or noradrenaline, extent of innervation of cholinergic, GABA-ergic, dopaminergic and noradrenergic fibers were analysed in discrete brain areas and subareas of the baboon and the rabbit with a special reference to the hypothalamus and the preoptic ares. In the latter area, cholinergic and dopaminergic innervation increases medio-lateraly on the one hand, and noradrenergic innervation reversed on the other hand. GABA-ergic innervation is almost evenly distributed in this structure. By placing electrical lesions in the lateral hypothalamus, an analysis was made of inputs of these innervations.