Retinohypothalamic projections in the Common Marmoset (Callithrix jacchus): a study using cholera toxin subunit B

Retinal projections in vertebrates reach the primary visual, accessory optic, and circadian timing structures. The central feature of the circadian timing system is the principal circadian pacemaker, the suprachiasmatic nucleus (SCN) of the hypothalamus. The direct projections from the retina to the...

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Detalles Bibliográficos
Autores: Costa, Mirian Stela Maris de Oliveira, Santee, U. R., Cavalcante, J. S., Moraes, Paulo Ranieri de Araújo, Santos, N. P., Britto, L. R. G.
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:1999
País:Brasil
Institución:Universidade Federal do Rio Grande do Norte (UFRN)
Repositorio:Repositório Institucional da UFRN
Idioma:inglés
OAI Identifier:oai:repositorio.ufrn.br:123456789/31099
Acceso en línea:https://repositorio.ufrn.br/handle/123456789/31099
Access Level:acceso abierto
Palabra clave:Circadian rhythms
Suprachiasmatic nucleus
Subcortical visual pathways
Hypothalamic nuclei
Retinohypothalamic tract
Descripción
Sumario:Retinal projections in vertebrates reach the primary visual, accessory optic, and circadian timing structures. The central feature of the circadian timing system is the principal circadian pacemaker, the suprachiasmatic nucleus (SCN) of the hypothalamus. The direct projections from the retina to the SCN are considered the entrainment pathway of the circadian timing system. In this study, unilateral intravitreal injections of cholera toxin subunit B were used to trace the retinal projections to the marmoset hypothalamus. The retinohypothalamic tract reaches the ventral suprachiasmatic nucleus bilaterally, as anticipated from previous studies. However, labeled fibers were found in several other hypothalamic regions, such as the medial and lateral preoptic areas, supraoptic nucleus, anterior and lateral hypothalamic areas, retrochiasmatic area, and subparaventricular zone. These results reveal new aspects of retinohypothalamic projection in primates and are discussed in terms of their implications for circadian as well as noncircadian control systems.