Cytoarchitecture and axonal systems in the commissural nucleus of the inferior colliculus in the albino rat. A Golgi study.
The nucleus commissuralis (Ncom) of the inferior colliculus in the rat is cytoarchitectonically divided in four zones: 1) subpial; 2) plexiform dendritic; 3) central and 4) ventral. Each zone possesses definitory neuronal types. The first three zones are innervated by fibres from the dorsal cortex. These fibres arborizes in varied manner in some cases forming axonal nests. Also vertical fibres from deeper zones of the Ncom contribute to the intrinsic vertical axonal system of the Ncom and innervate these zones, in particular fusiform neurons of the central zone. Fusiform and stellate neurons of the central zone also contribute to this vertical axonal system and to the intrinsic circuitry of the Ncom. Some specific types of the dorsal periaqueductal gray (PAGd) are in close relationship with the Ncom. Fusiform and stellate cells of the PAGd send in variable degree their dendrites and in some cases their axons to the commissural neuropil. In turn transverse and vertical fibres from the Ncom arborize in the upper part of the PAGd. This suggest the existence of discrete cell groups in PAGd in relation with the auditory cellular nuclei of the colliculus.
Herrera
M
M
Departamento de Morfologia, Facultad de Medicina, Universidad de Alicante, España.
Sanchez del Campo
F
F
Puchades Orts
A
A
D000818:Animals; D001369:Axons / Q000648:ultrastructure*; D006056:Golgi Apparatus / Q000648:ultrastructure; D007245:Inferior Colliculi / Q000033:anatomy & histology* / Q000166:cytology; D009474:Neurons / Q000166:cytology; D051381:Rats; D011919:Rats, Inbred Strains / Q000033:anatomy & histology*; D013194:Staining and Labeling