Locus coeruleus neurons in the rat containing neuropeptide Y, tyrosine hydroxylase or galanin and their efferent projections to the spinal cord, cerebral cortex and hypothalamus

摘要: Abstract The efferent projections of locus coeruleus neurons which contain neuropeptide Y-, tyrosine hydroxylase- or galanin-like immunoreactivity were investigated using the indirect immunofluorescence technique combined with retrograde transport fluorescent substance Fast Blue. Four groups rats received injections Blue: (1)bilaterally into mid-thoracic spinal cord (T6–T7) (2)unilaterally low cervical (C4–C5) (3)unilaterally paraventricular, periventricular and dorsomedial hypothalamic nuclei (4)unilaterally five sites in cerebral cortex (frontal, cingulate striate cortex). Efferent to cord, hypothalamus from galanin-containing cells observed. A higher percentage peptidergic projected than cortex. distribution morphology Y- also investigated. Neuropeptide Y-like found small, medium large multipolar neurons, as well fusiform cells. galanin-immunoreactive throughout coeruleus. In caudal coeruleus, they primarily located dorsal portion. only seen a few hydroxylasepositive subcoeruleus group. data show that peptide-containing have may be divided functional subdivisions dependent on region neurotransmitter/neuropeptide(s) contained within their projections.