Heterogeneity of the Endocannabinoid System Between Cerebral Cortex and Spinal Cord Oligodendrocytes

The central nervous system develops from a proliferating tube of cells and retains a tubular organization in the adult spinal cord and brain, including the forebrain. Failure of the neural tube to close at the front is lethal, whereas failure to close the tube at the back end produces spina bifida, a serious neural tube defect. Swellings in the neural tube develop into the hindbrain, midbrain, diencephalon, and telencephalon. The diencephalon sends an outpouching out of the cranium to form the retina, providing an accessible window onto the brain. The dorsal telencephalon forms the cerebral cortex, which in humans is enormously expanded by growth in every direction. Running through the embryonic neural tube is an internal lumen that becomes the cerebrospinal fluid–containing ventricular system. The effects of damage to the spinal cord and forebrain are compared with respect to impact on self and potential for improvement.

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

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

10.1017/s031716710011933x ◽

1979 ◽

Vol 6 (1) ◽

pp. 27-37 ◽

Cited By ~ 1

Author(s):

R. Marchand ◽

M. Fantino ◽

J. Dankova ◽

L.J. Poirier

Keyword(s):

Spinal Cord ◽

Cerebral Cortex ◽

Locus Coeruleus ◽

Marked Decrease ◽

Important Change ◽

Contralateral Cortex ◽

Parabrachial Nuclei ◽

Bilateral Lesions

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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THC Exposure is Reflected in the Microstructure of the Cerebral Cortex and Amygdala of Young Adults

Cerebral Cortex ◽

10.1093/cercor/bhaa087 ◽

2020 ◽

Vol 30 (9) ◽

pp. 4949-4963 ◽

Cited By ~ 2

Author(s):

Ryan P Cabeen ◽

John M Allman ◽

Arthur W Toga

Keyword(s):

Young Adults ◽

Cerebral Cortex ◽

Molecular Mechanisms ◽

Cannabinoid Receptor ◽

Memory Performance ◽

Critical Role ◽

Endocannabinoid System ◽

Imaging Data ◽

Brain Areas ◽

Human Connectome Project

Abstract The endocannabinoid system serves a critical role in homeostatic regulation through its influence on processes underlying appetite, pain, reward, and stress, and cannabis has long been used for the related modulatory effects it provides through tetrahydrocannabinol (THC). We investigated how THC exposure relates to tissue microstructure of the cerebral cortex and subcortical nuclei using computational modeling of diffusion magnetic resonance imaging data in a large cohort of young adults from the Human Connectome Project. We report strong associations between biospecimen-defined THC exposure and microstructure parameters in discrete gray matter brain areas, including frontoinsular cortex, ventromedial prefrontal cortex, and the lateral amygdala subfields, with independent effects in behavioral measures of memory performance, negative intrusive thinking, and paternal substance abuse. These results shed new light on the relationship between THC exposure and microstructure variation in brain areas related to salience processing, emotion regulation, and decision making. The absence of effects in some other cannabinoid-receptor-rich brain areas prompts the consideration of cellular and molecular mechanisms that we discuss. Further studies are needed to characterize the nature of these effects across the lifespan and to investigate the mechanistic neurobiological factors connecting THC exposure and microstructural parameters.

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