Lateral parabrachial neurons innervate orexin neurons projecting to brainstem arousal areas in the rat.

ABSTRACT: Orexin (ORX) neurons in the hypothalamus send their axons to arousal-promoting areas. We have previously shown that glutamatergic neurons in the lateral parabrachial nucleus (LPB) innervate ORX neurons. In this study, we examined potential pathways from the LPB to ORX neurons projecting to arousal-promoting areas in the brainstem by a combination of tract-tracing techniques in male Wistar rats. We injected the anterograde tracer biotinylated dextranamine (BDA) into the LPB and the retrograde tracer cholera toxin B subunit (CTb) into the ventral tegmental area, dorsal raphe nucleus, pedunculopontine tegmental nucleus, laterodorsal tegmental area, or locus coeruleus (LC). We then analyzed the BDA-labeled fibers and ORX-immunoreactive neurons in the hypothalamus. We found that double-labeled

SUBMITTER: Arima Y 

PROVIDER: S-EPMC6391479 | biostudies-literature | 2019 Feb

REPOSITORIES: biostudies-literature