Correlations Histopathologiques et Neurochimiques en Fonction de Lesions de la Regiondu Locus Coeruleus chez le Chat (Part I)

SummaryUnilateral lesions in the area of the loci coeruleus and subcoeruleus in the cat are associated with a significant and sustained decrease of noradrenaline (NA) in the ipsilateral cerebral cortex without any important change in the concentrations of NA in the contralateral cortex and in the spinal cord of both sides. The serotonin (5-HT) concentrations of the spinal cord and cerebral cortex of both sides remained unchanged in the same groups of animals. Bilateral lesions in the same area result also in a marked decrease of NA in the cerebral cortex of both sides. The latter lesions also result in slight decreases of NA in the hypothalamus and of NA and 5-HT in the spinal cord but the NA and 5-HT concentrations of the stria-turn and thalamus and the 5-H T concentrations of the cerebral cortex and hypothalamus are unmodified by such lesions. Unilateral lesions of the area immediately rostral to the locus coeruleus (praelocus lesions) result in a very significant decrease of NA in the ipsilateral cerebral cortex without any change of NA in the contralateral cerebral cortex and spinal cord of both sides. Similar lesions produced bilaterally in another group of cats resulted in marked decreases of NA in the cerebral cortex of both sides and a slight decrease of NA in the thalamus without any change of NA in the striatum, hypothalamus and spinal cord and of 5-HT in the cerebral cortex. In the same group of animals with lesions which, however, extended more closely to the midline than in cats with locus coeruleus lesions, 5-HT is markedly decreased in the striatum and thalamus and slightly decreased in the hypothalamus and spinal cord.These results support the view that the noradrenergie coeruleo-cortical pathway is made up of fibers which originate in the loci coeruleus and subcoeruleus and pre-dominently end ipsilaterally to their origin in the cerebral cortex. Ascending NA fibers ending in the thalamus appear to originate from NA neurons located more laterally in the upper pons and more specifically at the level of the parabrachial nuclei.

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Etude Histopathologique et Neurochimique Suite a des Lesions Unilaterales du Locus Coeruleus Chez le Rat et de la Region Postlocus Chez le Chat (Part 2)

Canadian Journal of Neurological Sciences / Journal Canadien des Sciences Neurologiques ◽

10.1017/s0317167100119493 ◽

1979 ◽

Vol 6 (2) ◽

pp. 113-122 ◽

Cited By ~ 4

Author(s):

R. Marchand ◽

P. Chauvel ◽

M. Fantino ◽

L.J. Poirier

Keyword(s):

Spinal Cord ◽

Cerebral Cortex ◽

Locus Coeruleus ◽

Marked Decrease ◽

Cerebellar Nuclei ◽

Companion Paper ◽

Important Change ◽

The Other ◽

Contralateral Cortex

SummaryUnilateral lesions involving the area immediately caudal to the locus coeruleus in the cat are associated with slight decreases of noradrenaline (NA) in both sides of the spinal cord without any important change of serotonin (5-HT) concentration in the spinal cord and of N A and 5-HT concentrations in the cerebral cortex of both sides. In other cats with similar lesions involving the same area bilaterally (postlocus lesions) NA is markedly decreased and 5-H T slightly decreased in the hypothalamus and spinal cord but the concentrations of NA and 5-HT of the cerebral cortex, striât urn and thalamus are not conspicuously modified by such postlocus lesions.Unilateral lesions in the area of the loci coeruleus and subcoeruleus in the rat are associated with a marked decrease of noradrenaline (NA) in the ipsilateral cerebral cortex without any important change of NA in the contralateral cortex and in the spinal cord of both sides. Under such conditions the concentrations of serotonin (5-HT) are not significantly modified in the cerebral cortex and spinal cord of both sides. NA and 5-HT concentrations of the cerebral cortex of both sides are unmodified by unilateral lesions of the cerebellar nuclei in the rat. In the latter group of animals slight increases of NA and 5-HT in the spinal cord are significant in comparison to the values obtained in the control animals but not from one side of the spinal cord to the other.These results further support the suggestion that the noradrenergic coeruleo-cortical pathway originating in the loci coeruleus and subcoeruleus ascends on the same side and ends in the ipsilateral cerebral cortex. In the light of the results of this investigation and of those reported in a companion paper (Marchand et ai, 1979) NA fibers reaching the hypothalamus and spinal cord most likely arise from neurons located caudally in respect to the locus coeruleus. Moreover NA fibers ending in the hypothalamus do not ascend in the dorsolateral part of the isthmic area and, therefore, have a different course than the N A fibers reaching the cerebral cortex and thalamus.

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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

Neuroscience ◽

10.1016/0306-4522(88)90076-0 ◽

1988 ◽

Vol 24 (3) ◽

pp. 893-906 ◽

Cited By ~ 276

Author(s):

V.R. Holets ◽

T. Hökfelt ◽

Å Rökaeus ◽

L. Terenius ◽

M. Goldstein

Keyword(s):

Spinal Cord ◽

Cerebral Cortex ◽

Tyrosine Hydroxylase ◽

Neuropeptide Y ◽

Locus Coeruleus ◽

Efferent Projections

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Comparisons of neuroinflammation, microglial activation, and degeneration of the locus coeruleus-norepinephrine system in APP/PS1 and aging mice

Journal of Neuroinflammation ◽

10.1186/s12974-020-02054-2 ◽

2021 ◽

Vol 18 (1) ◽

Author(s):

Song Cao ◽

Daniel W. Fisher ◽

Guadalupe Rodriguez ◽

Tian Yu ◽

Hongxin Dong

Keyword(s):

Spinal Cord ◽

Locus Coeruleus ◽

Microglial Activation ◽

Healthy Aging ◽

Cell Types ◽

Norepinephrine System ◽

Protective Processes ◽

The Central Nervous System ◽

Brain And Spinal Cord ◽

The Brain

Abstract Background The role of microglia in Alzheimer’s disease (AD) pathogenesis is becoming increasingly important, as activation of these cell types likely contributes to both pathological and protective processes associated with all phases of the disease. During early AD pathogenesis, one of the first areas of degeneration is the locus coeruleus (LC), which provides broad innervation of the central nervous system and facilitates norepinephrine (NE) transmission. Though the LC-NE is likely to influence microglial dynamics, it is unclear how these systems change with AD compared to otherwise healthy aging. Methods In this study, we evaluated the dynamic changes of neuroinflammation and neurodegeneration in the LC-NE system in the brain and spinal cord of APP/PS1 mice and aged WT mice using immunofluorescence and ELISA. Results Our results demonstrated increased expression of inflammatory cytokines and microglial activation observed in the cortex, hippocampus, and spinal cord of APP/PS1 compared to WT mice. LC-NE neuron and fiber loss as well as reduced norepinephrine transporter (NET) expression was more evident in APP/PS1 mice, although NE levels were similar between 12-month-old APP/PS1 and WT mice. Notably, the degree of microglial activation, LC-NE nerve fiber loss, and NET reduction in the brain and spinal cord were more severe in 12-month-old APP/PS1 compared to 12- and 24-month-old WT mice. Conclusion These results suggest that elevated neuroinflammation and microglial activation in the brain and spinal cord of APP/PS1 mice correlate with significant degeneration of the LC-NE system.

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Expression of the raf protooncogene in glial cells of the adult rat cerebral cortex, brain stem and spinal cord

Acta Histochemica ◽

10.1016/s0065-1281(11)80172-8 ◽

1994 ◽

Vol 96 (2) ◽

pp. 155-164 ◽

Cited By ~ 1

Author(s):

András Mihály ◽

Ulf R. Rapp

Keyword(s):

Spinal Cord ◽

Cerebral Cortex ◽

Brain Stem ◽

Glial Cells ◽

Rat Cerebral Cortex ◽

Adult Rat

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Parabrachial and hypothalamic interaction in sodium appetite

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.00615.2010 ◽

2011 ◽

Vol 300 (5) ◽

pp. R1091-R1099 ◽

Cited By ~ 11

Author(s):

S. Dayawansa ◽

S. Peckins ◽

S. Ruch ◽

R. Norgren

Keyword(s):

Weight Loss ◽

Lateral Hypothalamus ◽

Ibotenic Acid ◽

The Other ◽

Salt Appetite ◽

Sodium Depletion ◽

Sodium Appetite ◽

Parabrachial Nuclei ◽

Bilateral Lesions

Rats with bilateral lesions of the lateral hypothalamus (LH) fail to exhibit sodium appetite. Lesions of the parabrachial nuclei (PBN) also block salt appetite. The PBN projection to the LH is largely ipsilateral. If these deficits are functionally dependent, damaging the PBN on one side and the LH on the other should also block Na appetite. First, bilateral ibotenic acid lesions of the LH were needed because the electrolytic damage used previously destroyed both cells and axons. The ibotenic LH lesions produced substantial weight loss and eliminated Na appetite. Controls with ipsilateral PBN and LH lesions gained weight and displayed robust sodium appetite. The rats with asymmetric PBN-LH lesions also gained weight, but after sodium depletion consistently failed to increase intake of 0.5 M NaCl. These results dissociate loss of sodium appetite from the classic weight loss after LH damage and prove that Na appetite requires communication between neurons in the LH and the PBN.

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