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Published on: August 18, 2020
Optic afferents to the parabrachial nucleus
Katherine V Fite1, Skirmantas Janusonis
1Neuroscience and Behavior Program, Tobin Hall, University of Massachusetts, Amherst 01003, USA. kfite@psych.umass.edu
Abstract:
Following intraocular injection of cholera toxin subunit B (CTB), optic afferents to the dorsal pontine region were observed in Mongolian gerbils, Chilean degus, and laboratory rats. CTB-positive optic axons emerge at the caudal pole of the superior colliculus, descend through the periaqueductal gray, and innervate the lateral parabrachial nucleus. This projection appears to be a continuation of the retinal pathway that innervates the dorsal raphe nucleus in these same species.
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