title: The Edinger-Westphal nucleus II: Hypothalamic afferents in the rat.
abstract: Numerous functions have been attributed to the Edinger-Westphal nucleus (EW), including those related to feeding behavior, pain control, alcohol consumption and the stress response. The EW is thought to consist of two parts: one controls accommodation, choroidal blood flow and pupillary constriction, primarily comprising cholinergic cells and projecting to the ciliary ganglion; and the other would be involved in the non-ocular functions mentioned above, comprising peptide-producing neurons and projecting to the brainstem, spinal cord and prosencephalic regions. Despite the fact that the EW is well known, its connections have yet to be described in detail. The aim of this work was to produce a map of the hypothalamic sources of afferents to the EW in the rat. We injected the retrograde tracer Fluoro-Gold into the EW, and using biotinylated dextran amine, injected into afferent sources as the anterograde control. We found retrogradely labeled cells in the following regions: subfornical organ, paraventricular hypothalamic nucleus, arcuate nucleus, lateral hypothalamic area, zona incerta, posterior hypothalamic nucleus, medial vestibular nucleus and cerebellar interpositus nucleus. After injecting BDA into the paraventricular hypothalamic nucleus, lateral hypothalamic area and posterior hypothalamic nucleus, we found anterogradely labeled fibers in close apposition to and potential synaptic contact with urocortin 1-immunoreactive cells in the EW. On the basis of our findings, we can suggest that the connections between the EW and the hypothalamic nuclei are involved in controlling stress responses and feeding behavior.
authors.affiliation: Laboratory of Chemical Neuroanatomy, Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, 05508-000 São Paulo, Brazil; Department of Anatomy, Institute of Biosciences, São Paulo State University, 18618-970 Botucatu, Brazil.
authors.forename: André V
authors.initials: AV
authors.lastname: da Silva
authors.forename: Kelly R
authors.initials: KR
authors.lastname: Torres
authors.forename: Carlos A
authors.initials: CA
authors.lastname: Haemmerle
authors.forename: Isabel C
authors.initials: IC
authors.lastname: Céspedes
authors.forename: Jackson C
authors.initials: JC
authors.lastname: Bittencourt
mesh_terms: D000344:Afferent Pathways / Q000033:anatomy & histology*; D000818:Animals; D001933:Brain Stem / Q000033:anatomy & histology*; D007031:Hypothalamus / Q000033:anatomy & histology*; D007150:Immunohistochemistry; D008297:Male; D051381:Rats; D020318:Rats, Long-Evans
keywords: Afferents; Arc; BDA; CART; CRF; ChAT; Corticotropin-releasing factor; Cy; DAB; Dk; EW; EWcp; Edinger–Westphal; Edinger–Westphal central projections; FB; FG; KPBS; LC; LHA; LHA(a); LHA(p); LHA(t); LPO; Long–Evans rats; Neuronal tracers; OVLT; PH; PVH; SFO; SO; Stress response; Ucn1; Urocortin 1; arcuate nucleus; biotinylated dextran amine; choline acetyltransferase; cocaine- and amphetamine-regulated transcript; corticotropin-releasing factor; cyanine; diaminobenzidine tetrahydrochloride; fast blue; fluoro-gold; immunoreactivity; ir; lateral hypothalamic area; lateral hypothalamic area, anterior part; lateral hypothalamic area, posterior (mammillary) part; lateral hypothalamic area, tuberal part; lateral preoptic area; locus coeruleus; nucleus of Darkschewitsch; organum vasculosum of the lamina terminalis; paraventricular nucleus of the hypothalamus; posterior hypothalamic nucleus; potassium phosphate-buffered saline; subfornical organ; supraoptic nucleus; urocortin 1