Effects of central sodium on epithelial sodium channels in rat brain

2010 ◽  
Vol 299 (1) ◽  
pp. R222-R233 ◽  
Author(s):  
Hong-Wei Wang ◽  
Md Shahrier Amin ◽  
Esraa El-Shahat ◽  
Bing S. Huang ◽  
Balwant S. Tuana ◽  
...  
Keyword(s):  
Choroid Plexus ◽  
Supraoptic Nucleus ◽  
Third Ventricle ◽  
Brain Regions ◽  
Neural Precursor Cells ◽  
Epithelial Sodium Channels ◽  
Artificial Cerebrospinal Fluid ◽  
Hypothalamic Nuclei ◽  
Hypothalamic Tissue ◽  
The Brain

We evaluated the effects of intracerebroventricular (icv) infusion of Na+-rich artificial cerebrospinal fluid (aCSF), with or without the mineralocorticoid receptor (MR) blocker spironolactone, on epithelial Na+ channel (ENaC) subunits and regulators, such as MR, serum/glucocorticoid-inducible kinase 1, neural precursor cells expressed developmentally downregulated 4-like gene, 11β-hydroxylase, and aldosterone synthase, in brain regions of Wistar rats. The effects of icv infusion of the amiloride analog benzamil on brain tissue and CSF Na+ concentration ([Na+]) were also assessed. In the choroid plexus and ependyma of the anteroventral third ventricle, ENaC subunits are present in apical and basal membranes. Na+-rich aCSF increased β-ENaC mRNA and immunoreactivity in the choroid plexus and increased α- and β-ENaC immunoreactivities in the ependyma. Na+-rich aCSF increased α- and β-ENaC-gold-labeled particles in the microvilli of the choroid plexus and in basolateral membranes of the ependyma. Spironolactone only prevented the increase in β-ENaC immunoreactivity in the choroid plexus and ependyma. In the supraoptic nucleus, paraventricular nucleus, and subfornical organ, Na+-rich aCSF did not affect mRNA expression levels of the studied genes. Benzamil significantly increased CSF [Na+] in the control, but not Na+-rich, aCSF group. In contrast, benzamil prevented the increase in hypothalamic tissue [Na+] by Na+-rich aCSF. These results suggest that CSF Na+ upregulates ENaC expression in the brain epithelia, but not in the neurons of hypothalamic nuclei. ENaC in the choroid plexus and ependyma appear to contribute to regulation of Na+ homeostasis in the brain.

Microsurgical anatomy of the posterior cerebral artery

1978 ◽  
Vol 48 (4) ◽  
pp. 534-559 ◽  
Author(s):  
Arnold A. Zeal ◽  
Albert L. Rhoton
Keyword(s):  
Choroid Plexus ◽  
Posterior Cerebral Artery ◽  
Third Ventricle ◽  
Cerebral Arteries ◽  
Temporal Artery ◽  
Microsurgical Anatomy ◽  
Content Type ◽  
Lateral Posterior ◽  
Calcarine Fissure ◽  
The Brain

✓ In order to define the microsurgical anatomy, 50 posterior cerebral arteries (PCA's) were examined using × 3 to × 40 magnification. The PC A was divided into four segments: Pt was the segment proximal to the posterior communicating artery (PCoA); P2 extended from the PCoA to the posterior margin of the midbrain and was subdivided into an equal anterior (P2A) and posterior (P2P) half; P3 began at the posterior midbrain, ran within the quadrigeminal cistern, and ended at the anterior limit of the calcarine fissure. The PCA had three types of branches: 1) cortical branches to the cerebrum; 2) central branches to the brain stem; and 3) ventricular branches to the choroid plexus. The largest branches reaching the lateral surface of the cerebrum were located immediately anterior to the preoccipital notch, and in most cases were branches of the posterior temporal artery. This area offers a greater than 75% chance of finding a vessel large enough to perform a microvascular anastomosis. The central branches were of two types: 1) direct perforating, and 2) circumferential. The direct perforating branches arising on P1 were the posterior thalamoperforating arteries. The “thalamogeniculate artery,” the vessel said to be occluded in the “thalamic syndrome,” was also of the direct perforating type, but it was a series of small arteries arising from P2A and P2P rather than being a single vessel. The circumferential arteries usually arose from P1 and encircled the midbrain providing branches as far posteriorly as the colliculi. The branches to the choroid plexus were the medial and lateral posterior choroidal arteries; the former usually arose from P2A and entered the roof of the third ventricle, and the latter arose as a series of arteries from P2P and passed over the pulvinar to enter the lateral ventricle.

Stimuli and consequences of dendritic release of oxytocin within the brain

2007 ◽  
Vol 35 (5) ◽  
pp. 1252-1257 ◽  
Author(s):  
I.D. Neumann
Keyword(s):  
Paraventricular Nucleus ◽  
Stress Responses ◽  
Supraoptic Nucleus ◽  
Brain Regions ◽  
Model System ◽  
Intracerebral Microdialysis ◽  
Psychotherapeutic Intervention ◽  
Psychiatric Illnesses ◽  
Oxytocin Release ◽  
The Brain

The brain oxytocin system has served as a distinguished model system in neuroendocrinology to study detailed mechanisms of intracerebral release, in particular of somatodendritic release, and its behavioural and neuroendocrine consequences. It has been shown that oxytocin is released within various brain regions, but evidence for dendritic release is limited to the main sites of oxytocin synthesis, i.e. the hypothalamic SON (supraoptic nucleus) and PVN (paraventricular nucleus). In the present paper, stimuli of dendritic release of oxytocin and the related neuropeptide vasopressin are discussed, including parturition and suckling, i.e. the period of a highly activated brain oxytocin system. Also, exposure to various pharmacological, psychological or physical stressors triggers dendritic oxytocin release, as monitored by intracerebral microdialysis within the SON and PVN during ongoing behavioural testing. So far, dendritic release of the neuropeptide has only been demonstrated within the hypothalamus, but intracerebral oxytocin release has also been found within the central amygdala and the septum in response to various stimuli including stressor exposure. Such a locally released oxytocin modulates physiological and behavioural reproductive functions, emotionality and hormonal stress responses, as it exerts, for example, pro-social, anxiolytic and antistress actions within restricted brain regions. These discoveries make oxytocin a promising neuromodulator of the brain for psychotherapeutic intervention and treatment of numerous psychiatric illnesses, for example, anxiety-related diseases, social phobia, autism and postpartum depression.

Neural input modulates osmotically stimulated release of vasopressin into the supraoptic nucleus

1996 ◽  
Vol 270 (5) ◽  
pp. E787-E792 ◽  
Author(s):  
M. Ludwig ◽  
M. F. Callahan ◽  
R. Landgraf ◽  
A. K. Johnson ◽  
M. Morris
Keyword(s):  
Supraoptic Nucleus ◽  
Third Ventricle ◽  
Cardiovascular Responses ◽  
Neural Input ◽  
Artificial Cerebrospinal Fluid ◽  
Extracellular Compartment ◽  
Osmotic Stimulation ◽  
Blood Pressure Responses ◽  
Osmotic Stimuli ◽  
Stimulation Of

The effects of lesioning of the anteroventral third ventricle (AV3V) region on vasopressin (VP) release into the supraoptic nucleus (SON) and blood in response to central and systemic osmotic stimulation were determined. Microdialysis probes were implanted bilaterally within the SON of male urethan-anesthetized rats with sham or AV3V lesions. Osmotic stimuli were administered intraperitoneally (3.5 M NaCl, 600 microliters/100 g body wt) and then via the microdialysis probes (1 M NaCl-artificial cerebrospinal fluid). AV3V lesions attenuated the response to systemic osmotic stimulation. The lesioned rats showed no increase in intranuclear VP release and reduced plasma VP (increase of 42.6 +/- 8.4 vs. 78.0 +/- 16.4 pg/ml) and blood pressure responses (7.1 +/- 2.3 vs. 19.6 +/- 3.2 mmHg) to intraperitoneal NaCl. In contrast, the endocrine and cardiovascular responses to direct osmotic stimulation of the nucleus were as seen in previous studies and seemed to be unaffected by the lesion. These results show that lesion of the AV3V region interrupts neuronal inputs which trigger VP secretion from the posterior pituitary as well as release into the extracellular compartment of the SON.

scholarly journals Increased expression of both short and long forms of prolactin receptor mRNA in hypothalamic nuclei of lactating rats

1999 ◽  
Vol 23 (1) ◽  
pp. 13-22 ◽  
Author(s):  
XJ Pi ◽  
DR Grattan
Keyword(s):  
Short Form ◽  
Post Partum ◽  
Prolactin Receptor ◽  
Brain Regions ◽  
Physiological Changes ◽  
Receptor Mrna ◽  
Reverse Transcription Pcr ◽  
Hypothalamic Nuclei ◽  
Long Form ◽  
The Brain

This study investigated expression of prolactin receptor (PRL-R) mRNA in selected hypothalamic nuclei of lactating rats (days 7-10 post partum) compared with dioestrous rats. Rat brains were frozen with liquid nitrogen and cut into coronal sections of 300 microm. From these sections, tissues were micropunched from the parietal cortex (CTX), choroid plexus (ChP), and five hypothalamic regions: supraoptic (SO), paraventricular (Pa), arcuate (Arc) and ventromedial hypothalamic (VMH) nuclei, and median eminence (ME). Expression of both short and long forms of PRL-R mRNA were evaluated by reverse transcription-PCR and Southern hybridisation. The results showed that the relative amount of short form mRNA in the ChP of lactating rats was significantly higher than in dioestrous rats. The short form of PRL-R mRNA was undetectable in the SO, Pa, VMH of dioestrous rats but was expressed at a significant level in lactating rats. Levels of long form mRNA in the ChP, SO, Pa and VMH in lactating rats were significantly increased compared with dioestrous rats. Moreover, the long form mRNA was induced in the CTX of lactating rats. In the Arc, levels of both forms of PRL-R mRNA tended to increase in lactating rats compared with dioestrous rats but changes were not statistically significant. Neither form of PRL-R mRNA was detectable in the ME in the two animal models. Increased expression of PRL-R mRNA in specific brain regions during lactation is consistent with the variety of PRL effects on the brain, and may help to explain profound physiological changes in the lactating mother.

scholarly journals Single-nucleus transcriptome analysis of human brain immune response in patients with severe COVID-19

2021 ◽  
Vol 13 (1) ◽  
Author(s):  
John F. Fullard ◽  
Hao-Chih Lee ◽  
Georgios Voloudakis ◽  
Shengbao Suo ◽  
Behnam Javidfar ◽  
...  
Keyword(s):  
Immune Response ◽  
Choroid Plexus ◽  
Transcriptome Analysis ◽  
Brain Regions ◽  
Postmortem Brain ◽  
Network Analyses ◽  
Postmortem Brain Tissue ◽  
Single Nucleus ◽  
The Impact ◽  
The Brain

Abstract Background Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, has been associated with neurological and neuropsychiatric illness in many individuals. We sought to further our understanding of the relationship between brain tropism, neuro-inflammation, and host immune response in acute COVID-19 cases. Methods Three brain regions (dorsolateral prefrontal cortex, medulla oblongata, and choroid plexus) from 5 patients with severe COVID-19 and 4 controls were examined. The presence of the virus was assessed by western blot against viral spike protein, as well as viral transcriptome analysis covering > 99% of SARS-CoV-2 genome and all potential serotypes. Droplet-based single-nucleus RNA sequencing (snRNA-seq) was performed in the same samples to examine the impact of COVID-19 on transcription in individual cells of the brain. Results Quantification of viral spike S1 protein and viral transcripts did not detect SARS-CoV-2 in the postmortem brain tissue. However, analysis of 68,557 single-nucleus transcriptomes from three distinct regions of the brain identified an increased proportion of stromal cells, monocytes, and macrophages in the choroid plexus of COVID-19 patients. Furthermore, differential gene expression, pseudo-temporal trajectory, and gene regulatory network analyses revealed transcriptional changes in the cortical microglia associated with a range of biological processes, including cellular activation, mobility, and phagocytosis. Conclusions Despite the absence of detectable SARS-CoV-2 in the brain at the time of death, the findings suggest significant and persistent neuroinflammation in patients with acute COVID-19.

scholarly journals Intracisternally Injected L-Proline Activates Hypothalamic Supraoptic, but Not Paraventricular, Vasopressin-Expressing Neurons in Conscious Rats

2011 ◽  
Vol 2011 ◽  
pp. 1-8 ◽  
Author(s):  
Yumi Takemoto
Keyword(s):  
Blood Pressure ◽  
Supraoptic Nucleus ◽  
Excitatory Amino Acid ◽  
Brain Regions ◽  
Double Labeling ◽  
Amino Acid Receptors ◽  
Freely Moving Rats ◽  
Artificial Cerebrospinal Fluid ◽  
Freely Moving ◽  
Labeling Approach

When injected into specific rat brain regions, the neurotransmitter candidate L-proline produces various cardiovascular changes through ionotropic excitatory amino acid receptors. The present study used an immunohistochemical double-labeling approach to determine whether intracisternally injected L-proline in freely moving rats, which increases blood pressure, activates hypothalamic vasopressin-expressing neurons and ventral medullary tyrosine-hydroxylase- (TH-) containing neurons. Following injection of L-proline, the number of activated hypothalamic neurons that coexpressed vasopressin and c-Fos was much greater in the supraoptic nucleus (SON) than in the paraventricular nucleus (PVN) of rats with increased blood pressure. The number of activated TH-containing neurons was significantly greater following L-proline treatment than following control injections of artificial cerebrospinal fluid (ACSF). These results clearly demonstrate that intracisternally injected L-proline activates hypothalamic supraoptic, but not paraventricular, vasopressin-expressing neurons and medullary TH-containing (A1/C1) neurons in freely moving rats.

Multimodal responses of preoptic and anterior hypothalamic neurons to thermal and nonthermal homeostatic parameters

1987 ◽  
Vol 65 (6) ◽  
pp. 1290-1298 ◽  
Author(s):  
Tetsuro Hori ◽  
Toshikazu Kiyohara ◽  
Toshihiro Nakashima ◽  
Masaaki Shibata ◽  
Hisao Koga
Keyword(s):  
Brain Regions ◽  
Principal Role ◽  
Neural Connections ◽  
Thermoregulatory Responses ◽  
Hypothalamic Nuclei ◽  
Degree Of Convergence ◽  
High Degree ◽  
Conscious Animals ◽  
The Brain

The hypothesis that thermosensitive neurons in the preoptic anterior hypothalamic nuclei (POAH) have a principal role in central thermoregulation is based on numerous findings, suggesting correlations between the activity of thermosensitive neurons and thermoregulatory responses. Such relationships have been observed during thermal (local and peripheral) and pharmacological stimulation, during modulation of neural inputs from extra-POAH brain regions, and during actual thermoregulatory responses. Recent studies using in vitro slice preparations and conscious animals have revealed that 40–70% of POAH thermosensitive neurons respond to nonthermal homeostatic parameters such as local osmolality, blood pressure, and nonthermal emotional stimuli. About two-thirds of the POAH thermosensitive neurons, which responded in monkeys during bar press thermoregulatory tasks, changed their activity during bar press feeding behavior. A high degree of convergence of thermal and nonthermal homeostatic signals on the POAH neurons, together with abundant neural connections between the POAH and divergent areas of the brain, suggests that POAH thermosensitive neurons may be involved in the coordination of thermoregulation and nonthermal autonomic and behavioral responses controlled from the hypothalamus.

Stimulation of oxytocin release within the supraoptic nucleus and into blood by CCK-8

1994 ◽  
Vol 267 (6) ◽  
pp. R1626-R1631 ◽  
Author(s):  
I. Neumann ◽  
R. Landgraf ◽  
Y. Takahashi ◽  
Q. J. Pittman ◽  
J. A. Russell
Keyword(s):  
Supraoptic Nucleus ◽  
Jugular Vein ◽  
Female Rats ◽  
Reproductive Behaviors ◽  
Vasopressin Release ◽  
Hypothalamic Nuclei ◽  
Oxytocin Release ◽  
Left And Right ◽  
Complex Regulation ◽  
The Brain

Simultaneous microdialysis in brain and blood was used to monitor the effects of systemic and central cholecystokinin octapeptide (CCK-8) on the release of oxytocin and vasopressin within the hypothalamic supraoptic nucleus (SON) as well as into blood of urethan-anesthetized female rats. Administration of CCK-8 (20 micrograms/kg iv) increased oxytocin contents in 30-min microdialysates sampled simultaneously within the SON (1.8-fold) and blood (2.4-fold, both P < 0.05) compared with prestimulation levels. In another experiment, after bilateral administration of CCK-8 directly into the SON (10 ng/0.5 microliter) via a microdialysis/infusion probe, oxytocin contents in dialysates sampled from the left and right SON were increased 2.3- and 1.7-fold (P < 0.05), respectively. In simultaneously sampled dialysates from the jugular vein, oxytocin content increased 2.3-fold (P < 0.05). In contrast, oxytocin in dialysates sampled outside the hypothalamic nuclei was not altered by systemic or central CCK-8. The direct infusion of CCK-8 into both SON increased the release of vasopressin within the SON 1.7-fold (P < 0.05) but failed to significantly change vasopressin release into blood. The present findings show a coordinated regulation of intranuclear and systemic release of oxytocin in response to systemic and central CCK-8 and provide further evidence for a possible involvement of endogenous oxytocin in the complex regulation of ingestive and reproductive behaviors induced by CCK-8 at the brain level.

scholarly journals Hypothalamic dopamine neurons control sensorimotor behavior by modulating brainstem premotor nuclei

2020 ◽  
Author(s):  
Joshua P. Barrios ◽  
Wei-Chun Wang ◽  
Roman England ◽  
Erica Reifenberg ◽  
Adam D. Douglass
Keyword(s):  
Sensorimotor Integration ◽  
Motor Behavior ◽  
Third Ventricle ◽  
Dopamine Neurons ◽  
Preoptic Nucleus ◽  
Anatomy And Physiology ◽  
Motor Behaviors ◽  
Hypothalamic Nuclei ◽  
The Brain ◽  
Hypothalamic Dopamine

SummaryDopamine (DA)-producing neurons are critically involved in the production of motor behaviors in multiple circuits that are conserved from basal vertebrates to mammals. While there is increasing evidence that DA neurons in the hypothalamus play a locomotor role, their precise contributions to behavior and the circuit mechanisms by which they are achieved remain unclear. Here we demonstrate that tyrosine hydroxylase 2-expressing (th2+) DA neurons in the zebrafish hypothalamus fire phasic bursts of activity to acutely promote swimming and modulate audiomotor behaviors on fast timescales. Their anatomy and physiology reveal two distinct functional DA modules within the hypothalamus. The first comprises an interconnected set of cerebrospinal fluid-contacting DA nuclei surrounding the third ventricle, which lack distal projections outside of the hypothalamus and influence locomotion through unknown means. The second includes neurons in the preoptic nucleus, which send long-range projections to targets throughout the brain, including the mid- and hindbrain, where they activate premotor circuits involved in swimming and sensorimotor integration. These data suggest a broad regulation of motor behavior by DA neurons within multiple hypothalamic nuclei and elucidate a novel functional mechanism for the preoptic DA neurons in the initiation of movement.

Brain activation following peripheral administration of the GLP-1 receptor agonist exendin-4

2011 ◽  
Vol 301 (4) ◽  
pp. R1011-R1024 ◽  
Author(s):  
Elena-Dana Baraboi ◽  
David H. St-Pierre ◽  
Julie Shooner ◽  
Elena Timofeeva ◽  
Denis Richard
Keyword(s):  
Vagus Nerve ◽  
Mrna Expression ◽  
Supraoptic Nucleus ◽  
Brain Activation ◽  
Brain Regions ◽  
Nodose Ganglion ◽  
Central Regions ◽  
The Brain ◽  
Pituitary Adrenal Axis

The aim of our study was to investigate the anorectic and brain stimulatory effects of various doses of exendin-4 (Ex-4) and to investigate the role of the vagus nerve in Ex-4-induced brain activation. A dose-related increase in c- fos mRNA expression was observed following Ex-4 administration (0.155–15.5 μg/kg). Doses of Ex-4 that caused anorexia without aversive effects (0.155, 0.775 μg/kg) induced c- fos expression in the hypothalamic arcuate and paraventricular (PVH; parvocellular) nuclei as well as in the limbic and brainstem structures. Doses of Ex-4 that caused aversion (1.55, 15.5 μg/kg) stimulated the same regions (in a more intense way) and additionally activated the magnocellular hypothalamic structures (supraoptic nucleus and PVH magnocellular). The brain c- fos pattern induced by Ex-4 showed both similarities and differences with that induced by refeeding. Subdiaphragmatic vagotomy significantly blunted the stimulation of c- fos mRNA expression induced by Ex-4 in the nodose ganglion, the medial part of nucleus of the solitary tract, and the parvocellular division of the PVH. Pretreatment with Ex-9-39 (330 μg/kg ip) impaired the neuronal activation evoked by Ex-4 in all brain regions and in the nodose ganglion. Effects of Ex-4 on hypothalamic-pituitary-adrenal axis activity were not altered by vagotomy. Results of this study demonstrate and relate the anorectic and brain stimulatory effects of aversive and nonaversive doses of Ex-4 and indicate that the activation of specific central regions induced by the peripheral administration of Ex-4 is, at least in part, dependent on the integrity of the vagus nerve.

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