The Effects of Stress on Glutamatergic Transmission in the Brain

The brain is highly susceptible to adverse effects of drugs of abuse during early phases of life. Prenatal nicotine exposure (PNE), a preventable cause of gestational and infant mortality, can alter neuron wiring and induce sustained deficits in attention and learning. Here, a rat model of PNE (embryonic days 7–21) was used to examine the maturing hippocampus, which encodes new memories and processes emotional memory. Components of synaptic signaling were evaluated at postnatal day 14 (P14), a period of prolific synaptogenesis in rats, to determine if glutamatergic transmission-associated molecules are regulated in subregions of hippocampus as early as P14. PNE resulted in reduced expression of GluN2B, GluA2 and CaMKIIα, but elevated SNAP25 proteins specifically in the CA3 but not CA1. Only CaMKIIα was regulated in dentate gyrus at this age. These results suggest that glutamatergic and synaptic dysregulation of learning and memory may occur in hippocampus in a temporally and subregionally specific manner.

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Ketamine improves depressive symptoms caused by stress and induces c-Fos expression in the brain resembling some effects of stress

10.26226/morressier.5b681760b56e9b005965c6d7 ◽

2018 ◽

Author(s):

Nikolay Dygalo ◽

Tatyana Kalinina ◽

Galina T. Shishkina

Keyword(s):

Depressive Symptoms ◽

Fos Expression ◽

Effects Of Stress ◽

The Brain

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Morphological and Calcium Signaling Alterations of Neuroglial Cells in Cerebellar Cortical Dysplasia Induced by Carmustine

Cells ◽

10.3390/cells10071581 ◽

2021 ◽

Vol 10 (7) ◽

pp. 1581

Author(s):

Cynthia Alejandra Rodríguez-Arzate ◽

Marianne Lizeth Martínez-Mendoza ◽

Israel Rocha-Mendoza ◽

Yryx Luna-Palacios ◽

Jacob Licea-Rodríguez ◽

...

Keyword(s):

Neuronal Migration ◽

Brain Cortex ◽

Motor Coordination ◽

Cortical Dysplasia ◽

Experimental Models ◽

Glutamatergic Transmission ◽

Intracellular Calcium Dynamics ◽

Cortical Dysplasias ◽

The Brain

Cortical dysplasias are alterations in the organization of the layers of the brain cortex due to problems in neuronal migration during development. The neuronal component has been widely studied in experimental models of cortical dysplasias. In contrast, little is known about how glia are affected. In the cerebellum, Bergmann glia (BG) are essential for neuronal migration during development, and in adult they mediate the control of fine movements through glutamatergic transmission. The aim of this study was to characterize the morphology and intracellular calcium dynamics of BG and astrocytes from mouse cerebellum and their modifications in a model of cortical dysplasia induced by carmustine (BCNU). Carmustine-treated mice were affected in their motor coordination and balance. Cerebellar dysplasias and heterotopias were more frequently found in lobule X. Morphology of BG cells and astrocytes was affected, as were their spontaneous [Ca2+]i transients in slice preparation and in vitro.

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NGF Eye Administration Recovers the TrkB and Glutamate/GABA Marker Deficit in the Adult Visual Cortex Following Optic Nerve Crush

International Journal of Molecular Sciences ◽

10.3390/ijms221810014 ◽

2021 ◽

Vol 22 (18) ◽

pp. 10014

Author(s):

Pamela Rosso ◽

Elena Fico ◽

Louise A. Mesentier-Louro ◽

Viviana Triaca ◽

Alessandro Lambiase ◽

...

Keyword(s):

Visual Cortex ◽

Optic Nerve ◽

Optic Nerve Crush ◽

Glutamatergic Transmission ◽

Cell Soma ◽

Nerve Crush ◽

Cellular Targets ◽

Activity Dependent ◽

Human Nerve ◽

The Brain

Eye-drop recombinant human nerve growth factor (ed-rhNGF) has proved to recover the retina and optic nerve damage in animal models, including the unilateral optic nerve crush (ONC), and to improve visual acuity in humans. These data, associated with evidence that ed-rhNGF stimulates the brain derived neurotrophic factor (BDNF) in retina and cortex, suggests that NGF might exert retino-fugal effects by affecting BDNF and its receptor TrkB. To address these questions, their expression and relationship with the GABAergic and glutamatergic transmission markers, GAD65 and GAD67, vesicular inhibitory amino acid transporter (VGAT), and vesicular glutamate transporters 1 and 2 (VGLUT-1 and VGLUT-2) were investigated in adult ONC rats contralateral and ipsilateral visual cortex (VCx). Ed-rhNGF recovers the ONC-induced alteration of GABAergic and glutamatergic markers in contralateral VCx, induces an upregulation of TrkB, which is positively correlated with BDNF precursor (proBDNF) decrease in both VCx sides, and strongly enhances TrkB+ cell soma and neuronal endings surrounded by GAD65 immuno-reactive afferents. These findings contribute to enlarging the knowledge on the mechanism of actions and cellular targets of exogenously administrated NGF, and suggest that ed-rhNGF might act by potentiating the activity-dependent TrkB expression in GAD+ cells in VCx following retina damage and/or ONC.

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NMDA Receptor Hypofunction in the Aging-Associated Malfunction of Peripheral Tissue

Frontiers in Physiology ◽

10.3389/fphys.2021.687121 ◽

2021 ◽

Vol 12 ◽

Author(s):

Angélica Rivera-Villaseñor ◽

Frida Higinio-Rodríguez ◽

Laura Nava-Gómez ◽

Bárbara Vázquez-Prieto ◽

Isnarhazni Calero-Vargas ◽

...

Keyword(s):

Corpus Cavernosum ◽

Blood Perfusion ◽

Peripheral Tissue ◽

Glutamatergic Transmission ◽

Renal Glomerulus ◽

Potential Therapeutic Target ◽

Peripheral Tissues ◽

Proliferation And Differentiation ◽

The Brain ◽

Slow Turnover

Glutamatergic transmission through NMDA receptors (NMDARs) is important for the function of peripheral tissues. In the bone, NMDARs and its co-agonist, D-serine participate in all the phases of the remodeling. In the vasculature, NMDARs exerts a tonic vasodilation decreasing blood perfusion in the corpus cavernosum and the filtration rate in the renal glomerulus. NMDARs are relevant for the skin turnover regulating the proliferation and differentiation of keratinocytes and the formation of the cornified envelope (CE). The interference with NMDAR function in the skin leads to a slow turnover and repair. As occurs with the brain and cognitive functions, the manifestations of a hypofunction of NMDARs resembles those observed during aging. This raises the question if the deterioration of the glomerular vasculature, the bone remodeling and the skin turnover associated with age could be related with a hypofunction of NMDARs. Furthermore, the interference of D-serine and the effects of its supplementation on these tissues, suggest that a decrease of D-serine could account for this hypofunction pointing out D-serine as a potential therapeutic target to reduce or even prevent the detriment of the peripheral tissue associated with aging.

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Genetic dissection of the different roles of hypothalamic kisspeptin neurons in regulating female reproduction

eLife ◽

10.7554/elife.43999 ◽

2019 ◽

Vol 8 ◽

Cited By ~ 7

Author(s):

Luhong Wang ◽

Charlotte Vanacker ◽

Laura L Burger ◽

Tammy Barnes ◽

Yatrik M Shah ◽

...

Keyword(s):

Gonadotropin Releasing Hormone ◽

Genetic Dissection ◽

Glutamatergic Transmission ◽

Female Reproduction ◽

Positive Feedbacks ◽

Pulsatile Gnrh ◽

Lh Release ◽

Puberty Onset ◽

Reproductive Cycles ◽

The Brain

The brain regulates fertility through gonadotropin-releasing hormone (GnRH) neurons. Estradiol induces negative feedback on pulsatile GnRH/luteinizing hormone (LH) release and positive feedback generating preovulatory GnRH/LH surges. Negative and positive feedbacks are postulated to be mediated by kisspeptin neurons in arcuate and anteroventral periventricular (AVPV) nuclei, respectively. Kisspeptin-specific ERα knockout mice exhibit disrupted LH pulses and surges. This knockout approach is neither location-specific nor temporally controlled. We utilized CRISPR-Cas9 to disrupt ERα in adulthood. Mice with ERα disruption in AVPV kisspeptin neurons have typical reproductive cycles but blunted LH surges, associated with decreased excitability of these neurons. Mice with ERα knocked down in arcuate kisspeptin neurons showed disrupted cyclicity, associated with increased glutamatergic transmission to these neurons. These observations suggest that activational effects of estradiol regulate surge generation and maintain cyclicity through AVPV and arcuate kisspeptin neurons, respectively, independent from its role in the development of hypothalamic kisspeptin neurons or puberty onset.

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The Effect of Stress and Starvation on Bratn Serotonin Utilization in Arctic Charr (Salvelinus Alpinus)

Journal of Experimental Biology ◽

10.1242/jeb.165.1.229 ◽

1992 ◽

Vol 165 (1) ◽

pp. 229-239 ◽

Cited By ~ 2

Author(s):

SVANTE WINBERG ◽

GÖRAN E. NILSSON ◽

K. HÅKAN OLSÉN

Keyword(s):

Brain Stem ◽

Salvelinus Alpinus ◽

Arctic Charr ◽

Serotonergic Activity ◽

Brain Levels ◽

Hydroxyindoleacetic Acid ◽

Experimental Protocols ◽

Effects Of Stress ◽

The Brain ◽

Starvation Experiment

The effects of stress and starvation on brain levels of serotonin (5-HT) and 5-hydroxyindoleacetic acid (5-HIAA) were studied in Arctic charr (Salvelinus alpinus). Three experimental protocols were used to elucidate (1) the effect of stress in fish given food, (2) the effect of starvation, and (3) the effect of stress in fish deprived of food. In the stress experiments, fish were stressed three times a day over a four-week period, and in the starvation experiment the fish were starved for a four-week period. Stressed fish, whether given food or not, showed significantly higher concentrations of 5-HIAA, the main 5-HT metabolite, in both the telencephalon and the brain stem. The 5-HIAA/5-HT ratio (an index of serotonergic activity) was also significantly increased in the brain of stressed fish. In the telencephalon of starved fish, the 5-HT concentration was significantly decreased. However, starvation had no effect on 5-HIAA concentrations or 5-HIAA/5-HT ratios in either the telencephalon or the brain stem. These results suggest that stress increases brain serotonergic activity in Arctic charr, while starvation has no effect on the utilization of this transmitter system. It is suggested that stress could be a mediator of the increased 5-HTAA levels and 5-HIAA/5-HT ratios recently observed in low-ranking Arctic charr in a dominance hierarch.

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