title: Subcortical projections to the centromedian and parafascicular thalamic nuclei in the cat.
abstract: The primary objective of this study is to identify the totality of input to the centromedian and parafascicular (CM-Pf) thalamic nuclear complex. The subcortical projections upon the CM-Pf complex were studied in the cat with three different retrograde tracers. The tracers used were unconjugated horseradish peroxidase (HRP), horseradish peroxidase conjugated to wheat germ agglutinin (WGA-HRP), and rhodamine-labeled fluorescent latex microspheres (RFM). Numerous subcortical structures or substructures contained labeled neurons with all three tracing techniques. These labeled structures included the central nucleus of the amygdala; the entopeduncular nucleus; the globus pallidus; the reticular and ventral lateral geniculate nuclei of the thalamus; parts of the hypothalamus including the dorsal, lateral, and posterior hypothalamic areas and the ventromedial and parvicellular nuclei; the zona incerta and fields of Forel; parts of the substantia nigra including the pars reticularis and pars lateralis, and the retrorubral area; the pretectum; the intermediate and deep layers of the superior colliculus; the periaqueductal gray; the dorsal nucleus of the raphe; portions of the reticular formation, including the mesencephalic, pontis oralis, pontis caudalis, gigantocellularis, ventralis, and lateralis reticular nuclei; the nucleus cuneiformis; the marginal nucleus of the brachium conjunctivum; the locus coeruleus; portions of the trigeminal complex, including the principal sensory and spinal nuclei; portions of the vestibular complex, including the lateral division of the superior nucleus and the medial nucleus; deep cerebellar nuclei, including the medial and lateral cerebellar nuclei; and lamina VII of the cervical spinal cord. Moreover, the WGA-HRP and rhodamine methods (known to be more sensitive than the HRP method) revealed several afferent sources not shown by HRP: the anterior hypothalamic area, ventral tegmental area, lateral division of the superior vestibular nucleus, nucleus interpositus, and the nucleus praepositus hypoglossi. Also, the rhodamine method revealed labeled neurons in laminae V and VI of the cervical spinal cord.
authors.affiliation: Department of Anatomy, University of Wisconsin, Madison 53706.
authors.forename: G J
authors.initials: GJ
authors.lastname: Royce
authors.forename: S
authors.initials: S
authors.lastname: Bromley
authors.forename: C
authors.initials: C
authors.lastname: Gracco
mesh_terms: D000344:Afferent Pathways / Q000502:physiology; D000818:Animals; D001921:Brain / Q000502:physiology*; D002415:Cats / Q000033:anatomy & histology* / Q000502:physiology; D006735:Horseradish Peroxidase; D007840:Latex; D008863:Microspheres; D012235:Rhodamines; D013787:Thalamic Nuclei / Q000166:cytology* / Q000502:physiology; D014909:Wheat Germ Agglutinins
chemical_list: D007840:Latex; D012235:Rhodamines; D014909:Wheat Germ Agglutinins; D006735:Horseradish Peroxidase