scholarly journals AQP1 and AQP4 Contribution to Cerebrospinal Fluid Homeostasis

Cells ◽  
2019 ◽  
Vol 8 (2) ◽  
pp. 197 ◽  
Author(s):  
José Trillo-Contreras ◽  
Juan Toledo-Aral ◽  
Miriam Echevarría ◽  
Javier Villadiego
Keyword(s):  
Cerebrospinal Fluid ◽  
Water Channel ◽  
Ventricular Volume ◽  
Ependymal Cells ◽  
Brain Capillaries ◽  
Knock Out ◽  
Structural Functions ◽  
Ventricular Compliance ◽  
Specific Contribution ◽  
Csf Production

Aquaporin 1 (AQP1), expressed in epithelial cells of the choroid plexus, and aquaporin 4 (AQP4) present in ependymal cells and glia limitants have been proposed to play a significant role in cerebrospinal fluid (CSF) production and homeostasis. However, the specific contribution of each water channel to these functions remains unknown, being a subject of debate during the last years. Here, we analyzed in detail how AQP1 and AQP4 participate in different aspects of the CSF homeostasis such as the load and drainage of ventricles, and further explored if these proteins play a role in the ventricular compliance. To do that, we carried out records of intraventricular pressure and CSF outflow, and evaluated ventricular volume by magnetic resonance imaging in AQP1−/−, AQP4−/−, double AQP1−/−-AQP4−/− knock out and wild type mice controls. The analysis performed clearly showed that both AQPs have a significant participation in the CSF production, and additionally revealed that the double AQP1-AQP4 mutation alters the CSF drainage and the ventricular compliance. The data reported here indicate a significant extra-choroidal CSF formation mediated by AQP4, supporting the idea of an important and constant CSF production/absorption process, sustained by efflux/influx of water between brain capillaries and interstitial fluid. Moreover, our results suggest the participation of AQPs in structural functions also related with CSF homeostasis such as the distensibility capacity of the ventricular system.

Surgical removal of bilateral papillomas of the choroid plexus of the lateral ventricles with resolution of hydrocephalus

1979 ◽  
Vol 50 (5) ◽  
pp. 677-681 ◽  
Author(s):  
Steven K. Gudeman ◽  
Humbert G. Sullivan ◽  
Michael J. Rosner ◽  
Donald P. Becker
Keyword(s):  
Cerebrospinal Fluid ◽  
Choroid Plexus ◽  
Large Volume ◽  
Surgical Removal ◽  
Tumor Removal ◽  
Content Type ◽  
Lateral Ventricles ◽  
Csf Diversion ◽  
Csf Production ◽  
Fine Print

✓ The authors report a patient with bilateral papillomas of the choroid plexus of the lateral ventricles with documentation of cerebrospinal fluid (CSF) hypersecretion causing hydrocephalus. Special attention is given to the large volume of CSF produced by these tumors (removal of one tumor reduced CSF outflow by one-half) and to the fact that CSF diversion was not required after both tumors were removed. Since tumor removal alone was sufficient to stop the progression of hydrocephalus, we feel that this case supports the concept that elevated CSF production by itself is sufficient to cause hydrocephalus in patients with papillomas of the choroid plexus.

scholarly journals Increased Cerebrospinal Fluid Production as a Possible Mechanism Underlying Caffeine's Protective Effect against Alzheimer's Disease

2011 ◽  
Vol 2011 ◽  
pp. 1-6 ◽  
Author(s):  
Peter Wostyn ◽  
Debby Van Dam ◽  
Kurt Audenaert ◽  
Peter Paul De Deyn
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Cerebrospinal Fluid ◽  
Late Onset ◽  
Senile Plaques ◽  
Protective Effects ◽  
Caffeine Consumption ◽  
Neuroprotective Effects ◽  
Csf Production

Alzheimer's disease (AD), the most common type of dementia among older people, is characterized by the accumulation of β-amyloid (Aβ) senile plaques and neurofibrillary tangles composed of hyperphosphorylated tau in the brain. Despite major advances in understanding the molecular etiology of the disease, progress in the clinical treatment of AD patients has been extremely limited. Therefore, new and more effective therapeutic approaches are needed. Accumulating evidence from human and animal studies suggests that the long-term consumption of caffeine, the most commonly used psychoactive drug in the world, may be protective against AD. The mechanisms underlying the suggested beneficial effect of caffeine against AD remain to be elucidated. In recent studies, several potential neuroprotective effects of caffeine have been proposed. Interestingly, a recent study in rats showed that the long-term consumption of caffeine increased cerebrospinal fluid (CSF) production, associated with the increased expression of Na+-K+ATPase and increased cerebral blood flow. Compromised function of the choroid plexus and defective CSF production and turnover, with diminished clearance of Aβ, may be one mechanism implicated in the pathogenesis of late-onset AD. If reduced CSF turnover is a risk factor for AD, then therapeutic strategies to improve CSF flow are reasonable. In this paper, we hypothesize that long-term caffeine consumption could exert protective effects against AD at least in part by facilitating CSF production, turnover, and clearance. Further, we propose a preclinical experimental design allowing evaluation of this hypothesis.

Absence of orthogonal arrays in kidney, brain and muscle from transgenic knockout mice lacking water channel aquaporin-4

1997 ◽  
Vol 110 (22) ◽  
pp. 2855-2860 ◽  
Author(s):  
J.M. Verbavatz ◽  
T. Ma ◽  
R. Gobin ◽  
A.S. Verkman
Keyword(s):  
Cho Cells ◽  
Collecting Duct ◽  
Water Channel ◽  
Freeze Fracture ◽  
Orthogonal Arrays ◽  
Knock Out ◽  
Orthogonal Arrays Of Particles ◽  
Freeze Fracture Electron Microscopy ◽  
Knock Out Mice ◽  
And Function

Freeze-fracture electron microscopy (FFEM) of kidney collecting duct, muscle, astrocytes in brain, and other mammalian tissues has revealed regular square arrays of intramembrane particles called orthogonal arrays of particles (OAPs). Their possible role in membrane structure and transport have been proposed, and their absence or decrease has been noted in a variety of hereditary and acquired diseases. A transgenic mouse lacking water channel AQP4 was used to show that AQP4 is the OAP protein. FFEM was done on kidney, skeletal muscle, and brain from AQP4 wild-type [+/+], heterozygous [+/−] and knock-out [-/-] mice. The [-/-] mice did not express detectable AQP4 protein, but were grossly indistinguishable from [+/+] mice. FFEM was done on blinded samples of kidney, brain and muscle from 9 mice. In all 6 kidney samples from [+/+] and [+/−] mice, OAPs similar to those in AQP4-transfected CHO cells were found in basolateral membranes of collecting duct principal cells. In all muscle and brain samples from [+/+] and [+/−] mice, OAPs of identical ultrastructure to those in kidney were seen, but in smaller patch sizes. OAPs were not seen in any sample from [-/-] mice. Label-fracture analysis using a peptide-derived AQP4 polyclonal antibody showed immunogold labeling of OAPs in AQP4-expressing CHO cells. These studies provide direct evidence that AQP4 is required for formation of OAPs and is a component of OAPs, thus establishing the identity and function of OAPs.

scholarly journals Mechanism of Coup and Contrecoup Injuries Induced by a Knock-Out Punch

2020 ◽  
Vol 25 (2) ◽  
pp. 22 ◽  
Author(s):  
Milan Toma ◽  
Rosalyn Chan-Akeley ◽  
Christopher Lipari ◽  
Sheng-Han Kuo
Keyword(s):  
Cerebrospinal Fluid ◽  
Interaction Model ◽  
Brain Parenchyma ◽  
Primary Objective ◽  
Element Analysis ◽  
Knock Out ◽  
Particle Hydrodynamics ◽  
Smoothed Particle ◽  
The Impact ◽  
The Brain

Primary Objective: The interaction of cerebrospinal fluid with the brain parenchyma in an impact scenario is studied. Research Design: A computational fluid-structure interaction model is used to simulate the interaction of cerebrospinal fluid with a comprehensive brain model. Methods and Procedures: The method of smoothed particle hydrodynamics is used to simulate the fluid flow, induced by the impact, simultaneously with finite element analysis to solve the large deformations in the brain model. Main Outcomes and Results: Mechanism of injury resulting in concussion is demonstrated. The locations with the highest stress values on the brain parenchyma are shown. Conclusions: Our simulations found that the damage to the brain resulting from the contrecoup injury is more severe than that resulting from the coup injury. Additionally, we show that the contrecoup injury does not always appear on the side opposite from where impact occurs.

Cerebrospinal fluid formation and absorption in dehydrated sheep

1998 ◽  
Vol 275 (2) ◽  
pp. F235-F238 ◽  
Author(s):  
Adam Chodobski ◽  
Joanna Szmydynger-Chodobska ◽  
Michael J. McKinley
Keyword(s):  
Cerebrospinal Fluid ◽  
Adaptive Response ◽  
Venous Pressure ◽  
Extracellular Fluid ◽  
Cerebral Ventricles ◽  
Central Venous ◽  
Ventriculocisternal Perfusion ◽  
Fluid Formation ◽  
The Brain ◽  
Csf Production

Cerebrospinal fluid (CSF) plays an important role in the brain’s adaptive response to acute osmotic disturbances. In the present experiments, the effect of 48-h dehydration on CSF formation and absorption rates was studied in conscious adult sheep. Animals had cannulas chronically implanted into the lateral cerebral ventricles and cisterna magna to enable the ventriculocisternal perfusion. A 48-h water deprivation altered neither CSF production nor resistance to CSF absorption. However, in the water-depleted sheep, intraventricular pressure tended to be lower than that found under control conditions. This likely resulted from decreased extracellular fluid volume and a subsequent drop in central venous pressure occurring in dehydrated animals. In conclusion, our findings provide evidence for the maintenance of CSF production during mild dehydration, which may play a role in the regulation of fluid balance in the brain during chronic hyperosmotic stress.

Contribution of collagen matrix to passive left ventricular mechanics in isolated rat hearts

1994 ◽  
Vol 266 (3) ◽  
pp. H1007-H1018 ◽  
Author(s):  
D. A. MacKenna ◽  
J. H. Omens ◽  
A. D. McCulloch ◽  
J. W. Covell
Keyword(s):  
Extracellular Matrix ◽  
Dry Weight ◽  
Collagen Matrix ◽  
Ventricular Volume ◽  
Left Ventricular ◽  
Structural Protein ◽  
Ventricular Mechanics ◽  
Rat Hearts ◽  
Ventricular Compliance ◽  
Treated State

Although it makes up only 2-6% of left ventricular dry weight, collagen is thought to be the major structural protein determining passive ventricular stiffness. However, the relationship between structure of the extracellular matrix and passive mechanics is not understood. Hence, to deplete the collagen matrix, 16 rat hearts were perfused with bacterial collagenase for 60 min. Quantitative morphology using picrosirius red revealed a 36% decrease in collagen area fraction predominantly in the medium-sized fibers. Scanning electron microscopy revealed damage to the endomysial struts. Passive pressure-volume curves showed increases in left ventricular volume at all pressures (from 0.203 +/- 0.061 to 0.265 +/- 0.061 ml at 5 mmHg, P < 0.0001). Strain during loading, calculated from lengths obtained from a triplet of piezoelectric crystals, was unchanged with collagen depletion. However, remodeling strain computed from the collagenase-treated state referred to the Krebs solution-treated state at the same ventricular pressure showed both circumferential (0.145 +/- 0.166 to 0.170 +/- 0.158) and longitudinal (0.070 +/- 0.120 to 0.068 +/- 0.069) stretching. Sarcomere lengths increased at all depths (5.2% at midwall). Thus alterations in the extracellular matrix lead to increased ventricular volume and sarcomere lengths without altering ventricular compliance.

scholarly journals Alzheimer’s Disease-Associated Cerebrospinal Fluid (CSF) Biomarkers do not Correlate with CSF Volumes or CSF Production Rate

2017 ◽  
Vol 58 (3) ◽  
pp. 821-828 ◽  
Author(s):  
Mikael Edsbagge ◽  
Ulf Andreasson ◽  
Khalid Ambarki ◽  
Carsten Wikkelsø ◽  
Anders Eklund ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Cerebrospinal Fluid ◽  
Production Rate ◽  
Csf Biomarkers ◽  
Csf Production

Alterations in left ventricular compliance due to changes in right ventricular volume, pressure and compliance

1988 ◽  
Vol 22 (11) ◽  
pp. 768-776 ◽  
Author(s):  
W. P SANTAMORE ◽  
M. CONSTANTINESCU ◽  
J. VINTEN-JOHANSEN ◽  
W. E JOHNSTON ◽  
W. C LITTLE
Keyword(s):  
Right Ventricular ◽  
Ventricular Volume ◽  
Left Ventricular ◽  
Right Ventricular Volume ◽  
Ventricular Compliance ◽  
Left Ventricular Compliance

The effect of dexamethasone phosphate on the production rate of cerebrospinal fluid in the spinal subarachnoid space of dogs

1973 ◽  
Vol 39 (4) ◽  
pp. 480-484 ◽  
Author(s):  
Osamu Sato ◽  
Makoto Hara ◽  
Takehiko Asai ◽  
Ryuichi Tsugane ◽  
Naoki Kageyama
Keyword(s):  
Cerebrospinal Fluid ◽  
Production Rate ◽  
Subarachnoid Space ◽  
Content Type ◽  
Spinal Subarachnoid Space ◽  
Dexamethasone Phosphate ◽  
Maximal Reduction ◽  
Csf Production ◽  
Fine Print

✓ The effect of intravenous dexamethasone on cerebrospinal fluid (CSF) production was studied in dogs by a method of caudocephalad perfusion of the spinal subarachnoid space with an inulin-containing buffer. The CSF production rate began to reduce immediately after the injection of 0.15 mg/kg and attained a maximal reduction of 50% in 50 minutes.

Circadian variation in human cerebrospinal fluid production measured by magnetic resonance imaging

1992 ◽  
Vol 262 (1) ◽  
pp. R20-R24 ◽  
Author(s):  
C. Nilsson ◽  
F. Stahlberg ◽  
C. Thomsen ◽  
O. Henriksen ◽  
M. Herning ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Cerebrospinal Fluid ◽  
Magnetic Resonance ◽  
Circadian Variation ◽  
Repeated Measurements ◽  
Cerebral Aqueduct ◽  
Time Interval ◽  
Resonance Imaging ◽  
Fluid Production ◽  
Csf Production

Recent advances in magnetic resonance imaging have made it possible to visualize and quantify flow of cerebrospinal fluid (CSF) in the brain. The net flow of CSF through the cerebral aqueduct was used to measure CSF production in six normal volunteers at different times during a 24-h period. CSF production varied greatly both intra- and interindividually. The average CSF production in each time interval showed a clear tendency to circadian variation, with a minimum production 30% of maximum values (12 +/- 7 ml/h) approximately 1800 h and a nightly peak production approximately 0200 h of 42 +/- 2 ml/h. The total CSF production during the whole 24-h period, calculated as an average of all measurements, was 650 ml for the whole group and 630 ml for repeated measurements in each time interval in one of the volunteers.

Sign in / Sign up

Export Citation Format

Share Document