DISTRIBUTION OF CHOLINERGIC NEURONS AND FIBERS IN THE HYPOTHALAMUS OF THE CAT / 解剖学报

ABSTRACT

The cholinergic neurons and fibers of the hypothalamus could not be revealedsuccessfully in the past,therefore,there has been general agreement that the hypotha-lamus is very poorly innervated by cholinergic system.In this study,choline acetyl-trans ferase (ChAT)-like immunoreactive positive neurons and fibers of the hypo-thalamus were revealed successfully by using avidin-biotin immunocytochemical me-thod.This study demonstrated for the first time that the cat hypothalamus is richlyinnervated by cholinergic system.We found cholinergic neurons of varying numbersin the following areasdorsomedial hypothalamic nucleus,paraventricular nucleus,dorsal hypothalamic area,the area of the tuber cinereum surrounding ventromedialhypothalamic nucleus,lateral hypothalamic area,anterior hypothalamic area,anteriorhypothalamic nucleus,parvocellular hypothalamic nucleus,tuber-mammillary nucl-eus,posterior hypothalamic area,anterior mammillary nucleus and supramammillarynucleus.There were a lot of ChAT-like positive fibers in the lateral hypothalamicarea,mammillary area,dorsal hypothalamic area,paraventricular nucleus,parvocel-lular hypothalamic nucleus,the area of the tuber cinereum.Three kinds of neuronperikarya related to cholinergic system were identified in the hypothalamus of thecat1.cholinergic perikarya;2.noncholinergic-cholinoceptive perikarya;3.choli-nergic-cholinoceptive perikarya.There were also immunoreactive positive fiberswhich were non-varicose and varicose.Two kinds of varicose-fibers,one withstrong immunoreactivity and the other with weak immunoreactivity were distingui-shed.