Cerebrospinal fluid transients induced by hypercapnia

1983 ◽  
Vol 245 (5) ◽  
pp. R701-R705
Author(s):  
M. J. Fisher ◽  
S. R. Heisey ◽  
T. Adams ◽  
D. L. Traxinger
Keyword(s):  
Cerebrospinal Fluid ◽  
Formation Rate ◽  
Tracer Concentration ◽  
Perfusion Studies ◽  
Fluid Redistribution ◽  
Ventriculocisternal Perfusion ◽  
Before And After ◽  
Outflow Rate ◽  
The Times ◽  
Stop Flow

Ventriculocisternal perfusion studies using tracers have shown that hypercapnia causes a transient increase in cerebrospinal fluid (CSF) outflow rate (displaced CSF volume, Vd) and a decrease in CSF effluent tracer concentration (tracer-free CSF, CSFtf). This dilution could be due to an increase in CSF formation rate (Vf) and/or to displacement of unequilibrated CSFtf sequestered in poorly mixed compartments. To facilitate convection in the subarachnoid spaces, we used a “stop-flow” procedure (by clamping the cisternal outflow tube while infusion was constant) in anesthetized cats during ventriculocisternal perfusion with mock CSF containing [14C]dextran. Each animal spontaneously breathed air, then 5% CO2 both before and after stopflow. Although Vd and the times over which Vd and CSFtf were defined were unaffected, CSFtf was decreased by 50% after stop-flow. We conclude that during ventriculocisternal perfusion, mixing is incomplete in CSF spaces, and that unequilibrated CSF contributes significantly to the reduced tracer concentration in Vd during acute hypercapnia. To determine whether Vf transiently increases in response to CO2 breathing, or to any perturbation causing craniospinal fluid redistribution, homogeneity in CSF spaces must be verified.

Central role for angiotensin in control of adrenal catecholamine secretion

1985 ◽  
Vol 248 (3) ◽  
pp. R363-R370 ◽  
Author(s):  
E. J. Corwin ◽  
J. F. Seaton ◽  
M. Hamaji ◽  
T. S. Harrison
Keyword(s):  
Cerebrospinal Fluid ◽  
Catecholamine Secretion ◽  
Ang Ii ◽  
Artificial Cerebrospinal Fluid ◽  
Ventriculocisternal Perfusion ◽  
Before And After ◽  
Adrenal Response ◽  
Adrenal Secretion ◽  
Lateral Cerebral Ventricle

Angiotensin II (ANG II) is required for unimpaired adrenal reflex secretion of catecholamines after hemorrhage in the dog. To test if ANG II acts centrally, experiments were performed under general anesthesia on bilaterally or sham-nephrectomized dogs hemorrhaged at 25 ml/kg. Ventriculocisternal perfusion of ANG II or its antagonist saralasin was accomplished via needles inserted in the left lateral cerebral ventricle and cisterna magna. Mean arterial pressure and adrenal secretion of catecholamines were measured before and after hemorrhage. Nephrectomized dogs receiving only artificial cerebrospinal fluid (CSF) by ventriculocisternal perfusion had a very small adrenal response to hemorrhage compared with animals receiving ANG II intraventricularly (IVT) (at 10 and 100 pg . kg-1 . min-1). This effect of ANG II IVT also depended on the rate of IVT infusion. Peripheral infusion of ANG II (10 pg . kg-1 . min-1) had no effect on adrenal catecholamine secretion. Animals with intact kidneys given saralasin IVT (0.06 ng/min) responded similarly to nephrectomized dogs receiving only CSF IVT. Intravenous saralasin did not blunt the response to hemorrhage. Thus ANG II appears to support catecholamine secretion via a central mechanism. This mechanism is physiologically significant because either nephrectomy or functional elimination of ANG II by saralasin greatly attenuates the adrenal medullary response to hemorrhage in vivo.

The effect of cold-induced brain edema on cerebrospinal fluid formation rate

1980 ◽  
Vol 53 (5) ◽  
pp. 652-655 ◽  
Author(s):  
K. Gwan Go ◽  
Gerald M. Hochwald ◽  
Lenie Koster-Otte ◽  
Annie K. van Zanten ◽  
Mysore Gandhi
Keyword(s):  
Cerebrospinal Fluid ◽  
Brain Edema ◽  
Cerebral Perfusion ◽  
Perfusion Pressure ◽  
Formation Rate ◽  
Content Type ◽  
Ventriculocisternal Perfusion ◽  
Fluid Formation ◽  
Csf Formation Rate ◽  
Fine Print

✓ The net contribution of vasogenic brain edema to cerebrospinal fluid (CSF) formation was studied by ventriculocisternal perfusion. Individual cats were perfused both before and 2 ½ hours after a severe cold-induced injury to the cerebral cortex, and the results were compared. Although the edema had occupied the larger part of the hemispheric white matter and bordered the lateral ventricle, a decrease rather than an increase in CSF formation rate was observed. This decrease was related to a decrease in the cerebral perfusion pressure by a regression equation that was not affected by the cold injury.

The effect of intraventricular air on the rate of cerebrospinal fluid formation in dogs

1972 ◽  
Vol 37 (2) ◽  
pp. 177-181 ◽  
Author(s):  
Michael D. F. Deck ◽  
V. Deonarine ◽  
D. Gordon Potts
Keyword(s):  
Cerebrospinal Fluid ◽  
Statistical Analysis ◽  
Beagle Dogs ◽  
Content Type ◽  
Artificial Cerebrospinal Fluid ◽  
Ventriculocisternal Perfusion ◽  
Before And After ◽  
Fluid Formation ◽  
Fine Print

✓ Experiments were performed on dogs to estimate the effect of intraventricular air on the rate of cerebrospinal fluid formation. The rate of formation was measured satisfactorily in eight beagle dogs before and after the introduction of air using ventriculocisternal perfusion of artificial cerebrospinal fluid containing 14C-labelled inulin. Statistical analysis of rates of cerebrospinal fluid formation estimated half hourly indicated that there was little or no change after the introduction of air.

PCO(2) and rate of formation of cerebrospinal fluid in the monkey

1976 ◽  
Vol 231 (1) ◽  
pp. 127-131 ◽  
Author(s):  
AN Martins ◽  
TF Doyle ◽  
N Newby
Keyword(s):  
Blood Flow ◽  
Cerebrospinal Fluid ◽  
Nitrous Oxide ◽  
Cerebral Blood Flow ◽  
Rhesus Monkeys ◽  
Formation Rate ◽  
Perfusion Technique ◽  
Ventriculocisternal Perfusion ◽  
Fluid Formation ◽  
The Difference

Changes in cerebrospinal fluid formation rate (VF) with hypocapnia were measured by the ventriculocisternal perfusion technique in 24 rhesus monkeys anesthetized with nitrous oxide. In addition cerebral blood flow (CBF) was measured by the hydrogen clearence methods, Vf in control animals declined at a mean rate of 2.3 mul/min each hour during the last 4.5 h of a 7-h perfusion although variables known to effect Vf remained stable. Three hours after perfusion began, Vf of normocapnic controls was 41.4 mul/min +/- 5.4; CBF, 59P ML/100 G PER MIN. When Pco(2) was reduced to half of control, Vf fell to 35.6 mul/min +/- 6.3 and CBF fell by 27%. When Pco(2) was doubled, Vf fell to 33.1 mul/min +/- 5.3 and CBF increased threefold. The difference in Vf id significant only for the hypercapnic group (p=0.01). When animals were used as their own controls, three were no significant differences in Vf with hypercapnia compared to normocapnia. These results indicated that in the monkey variations of Pco(2) within broad physiologic limits, which are sufficient to cause large changes in CBF, have little effect of Vf.

Making Americans Feel Great Again? Personal Significance Predicts Political Intentions of Losers and Winners of the 2016 US Election

2017 ◽  
Author(s):  
Katarzyna Jasko ◽  
Joanna Grzymala-Moszczynska ◽  
Marta Maj ◽  
Marta Szastok ◽  
Arie W. Kruglanski
Keyword(s):  
Political System ◽  
Presidential Elections ◽  
The Political ◽  
Power Transition ◽  
Hillary Clinton ◽  
Donald Trump ◽  
Electoral Success ◽  
Personal Significance ◽  
Before And After ◽  
The Times

Reactions of losers and winners of political elections have important consequences for the political system during the times of power transition. In four studies conducted immediately before and after the 2016 US presidential elections we investigated how personal significance induced by success or failure of one’s candidate is related to hostile vs. benevolent intentions toward political adversaries. We found that the less significant supporters of Hillary Clinton and supporters of Donald Trump felt after an imagined (Study 1A) or actual (Study 2) electoral failure the more they were willing to engage in peaceful actions against the elected president and the less they were willing to accept the results of the elections. However, while significance gain due to an imagined or actual electoral success was related to more benevolent intentions among Clinton supporters (Study 1B), it was related to more hostile intentions among Trump supporters (Studies 1B, 2, and 3).

Simulation of Cerebrospinal Fluid Leak Repair Using a 3-Dimensional Printed Model

2021 ◽  
pp. 194589242110035
Author(s):  
Muhamed A. Masalha ◽  
Kyle K. VanKoevering ◽  
Omar S. Latif ◽  
Allison R. Powell ◽  
Ashley Zhang ◽  
...  
Keyword(s):  
Cerebrospinal Fluid ◽  
Great Part ◽  
Cerebrospinal Fluid Leak ◽  
Csf Leak ◽  
Clinical Environment ◽  
Training Tool ◽  
3 Dimensional ◽  
Clinical Scenarios ◽  
Before And After ◽  
3D Printed

Background Acquiring proficiency for the repair of a cerebrospinal fluid (CSF) leak is challenging in great part due to its relative rarity, which offers a finite number of training opportunities. Objective The purpose of this study was to evaluates the use of a 3-dimensional (3D) printed, anatomically accurate model to simulate CSF leak closure. Methods Volunteer participants completed two simulation sessions. Questionnaires to assess their professional qualifications and a standardized 5-point Likert scale to estimate the level of confidence, were completed before and after each session. Participants were also queried on the overall educational utility of the simulation. Results Thirteen otolaryngologists and 11 neurosurgeons, met the inclusion criteria. A successful repair of the CSF leak was achieved by 20/24 (83.33%), and 24/24 (100%) during the first and second simulation sessions respectively (average time 04:04 ± 1.39 and 02:10 ± 01:11). Time-to-close-the-CSF-leak during the second session was significantly shorter than the first (p < 0.001). Confidence scores increased across the training sessions (3.3 ± 1.0, before the simulation, 3.7 ± 0.6 after the first simulation, and 4.2 ± 0.4 after the second simulation; p < 0.001). All participants reported an increase in confidence and believed that the model represented a valuable training tool. Conclusions Despite significant differences with varying clinical scenarios, 3D printed models for cerebrospinal leak repair offer a feasible simulation for the training of residents and novice surgeons outside the constrictions of a clinical environment.

Evaluation of endorphin content in the CSF of patients with trigeminal neuralgia before and after Gasserian ganglion thermocoagulation

1981 ◽  
Vol 55 (6) ◽  
pp. 935-937 ◽  
Author(s):  
Giuseppe Salar ◽  
Salvatore Mingrino ◽  
Marco Trabucchi ◽  
Angelo Bosio ◽  
Carlo Semenza
Keyword(s):  
Cerebrospinal Fluid ◽  
Trigeminal Neuralgia ◽  
Control Group ◽  
Gasserian Ganglion ◽  
Content Type ◽  
Group Of Seven ◽  
Idiopathic Trigeminal Neuralgia ◽  
Significant Difference ◽  
Before And After ◽  
Fine Print

✓ The β-endorphin content in cerebrospinal fluid (CSF) was evaluated in 10 patients with idiopathic trigeminal neuralgia during medical treatment (with or without carbamazepine) and after selective thermocoagulation of the Gasserian ganglion. These values were compared with those obtained in a control group of seven patients without pain problems. No statistically significant difference was found between patients suffering from trigeminal neuralgia and those without pain. Furthermore, neither pharmacological treatment nor surgery changed CSF endorphin values. It is concluded that there is no pathogenetic relationship between trigeminal neuralgia and endorphins.

Changes on recovery in the concentrations of tryptophan and the biogenic amine metabolites in the cerebrospinal fluid of patients with affective illness

1973 ◽  
Vol 3 (3) ◽  
pp. 319-325 ◽  
Author(s):  
G. W. Ashcroft ◽  
Ivy M. Blackburn ◽  
D. Eccleston ◽  
A. I. M. Glen ◽  
W. Hartley ◽  
...  
Keyword(s):  
Cerebrospinal Fluid ◽  
Homovanillic Acid ◽  
Affective Illness ◽  
Normal Limits ◽  
Low Concentrations ◽  
Depressed Group ◽  
Before And After ◽  
Acid Metabolites ◽  
Bipolar Patients ◽  
Manic Patients

SYNOPSISThe concentration of the acid metabolites of dopamine, and 5-hydroxytryptamine (5-HT), homovanillic acid (HVA), and 5-hydroxyindolacetic acid (5-HIAA) respectively, were estimated in the cerebrospinal fluid of patients suffering from either unipolar or bipolar affective illness, both before and after recovery. Significantly low concentrations of HVA and 5-HIAA (P<0·01 and 0·05 respectively) were found in the unipolar depressed group and these did not return to normal on recovery. Depressed bipolar patients had levels within normal limits. In bipolar manic patients the HVA concentration fell on recovery to a level significantly lower (P<0·05) than controls. There was no difference in the levels of tryptophan in the CSF of any of the groups of patients nor was there any alteration on recovery. There was a high correlation between 5-HIAA and HVA in the same CSF. These findings are against the amine hypothesis which postulated in depression a lowered concentration of transmitter amine at synaptic junction.

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