Effect of noradrenalin on regional cerebral blood flow depending on initial state of the mean arterial pressure

1970 ◽  
Vol 69 (6) ◽  
pp. 608-610
Author(s):  
É. S. Gabrielyan ◽  
A. M. Harper
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Mean Arterial Pressure ◽  
Arterial Pressure ◽  
Regional Cerebral Blood Flow ◽  
Regional Cerebral Blood ◽  
Initial State ◽  
The Mean

The Effects of Paco2 on Regional Cerebral Blood Flow and Internal Carotid Arterial Pressure during Carotid Clamping

1971 ◽  
Vol 35 (3) ◽  
pp. 286-300 ◽  
Author(s):  
Gudru n ◽  
H. J. Ladegaard-Pedersen ◽  
H. Henriksen ◽  
L. Olesen ◽  
O. B. Paulson ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Arterial Pressure ◽  
Regional Cerebral Blood Flow ◽  
Internal Carotid ◽  
Regional Cerebral Blood ◽  
Carotid Arterial

Regional Cerebral Blood Flow in Patients with Affective Disorders

1990 ◽  
Vol 157 (3) ◽  
pp. 359-365 ◽  
Author(s):  
V. Delvenne ◽  
F. Delecluse ◽  
Ph. P. Hubain ◽  
A. Schoutens ◽  
V. De Maertelaer ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Regional Cerebral Blood Flow ◽  
Depressive Disorders ◽  
Endogenous Depression ◽  
Regional Cerebral Blood ◽  
Major Depressive Disorders ◽  
The Mean ◽  
Bipolar Patients ◽  
Tomographic Slice

Regional cerebral blood flow at rest was measured in 38 patients with major depressive disorders and 16 controls by SPECT with inhalation of xenon-133. All subjects had been withdrawn from medication. The mean hemispheric cerebral blood flow was not statistically different between the controls and the different subgroups of depressed patients defined either by biological markers or clinical characteristics. However, the predominantly cortical blood flow, measured on the outer cerebral rim of the third tomographic slice, was significantly lower on the left hemisphere in bipolar patients when compared with normals and unipolar patients. The same lateralisation was observed in patients with an endogenous depression according to the Newcastle scale.

Aging and Recognition Memory: Changes in Regional Cerebral Blood Flow Associated with Components of Reaction Time Distributions

1999 ◽  
Vol 11 (5) ◽  
pp. 511-520 ◽  
Author(s):  
David J. Madden ◽  
Lawrence R. Gottlob ◽  
Laura L. Denny ◽  
Timothy G. Turkington ◽  
James M. Provenzale ◽  
...  
Keyword(s):  
Older Adults ◽  
Blood Flow ◽  
Young Adults ◽  
Cerebral Blood Flow ◽  
Reaction Time ◽  
Task Performance ◽  
Regional Cerebral Blood Flow ◽  
Regional Cerebral Blood ◽  
Age Related ◽  
The Mean

We used H215O positron emission tomography (PET) to measure age-related changes in regional cerebral blood flow (rCBF) during a verbal recognition memory task. Twelve young adults (20 to 29 years) and 12 older adults (62 to 79 years) participated. Separate PET scans were conducted during Encoding, Baseline, and Retrieval conditions. Each of the conditions involved viewing a series of 64 words and making a two-choice response manually. The complete reaction time (RT) distributions in each task condition were characterized in terms of an ex-Gaussian model (convolution of exponential and Gaussian functions). Parameter estimates were obtained for the mean of the exponential component (τ), representing a task-specific decision process and the mean of the Gaussian component (μ), representing residual sensory coding and response processes. Independently of age group, both μ and τ were higher in the Encoding and Retrieval conditions than in the Baseline condition, and τ was higher during Retrieval than during Encoding. Age-related slowing in task performance was evident primarily in μ. For young adults, rCBF activation in the right prefrontal cortex, in the Retrieval condition, was correlated positively with μ but not with τ. For older adults, rCBF changes (both increases and decreases) in several cortical regions were correlated with both μ and τ. The data suggest that the attentional demands of this task are relatively greater for older adults and consequently lead to the recruitment of additional neural systems during task performance.

scholarly journals Regional Cerebral Blood Flow in Conscious Stroke-Prone Spontaneously Hypertensive Rats

1984 ◽  
Vol 4 (1) ◽  
pp. 103-106 ◽  
Author(s):  
Kent Fredriksson ◽  
Martin Ingvar ◽  
Barbro B. Johansson
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Arterial Pressure ◽  
Regional Cerebral Blood Flow ◽  
Brain Structures ◽  
Regional Cerebral Blood ◽  
Hypertensive Rats ◽  
Spontaneously Hypertensive ◽  
Cerebrovascular Resistance ◽  
Wistar Kyoto

Regional cerebral blood flow (rCBF) was measured autoradiographically with [14C]iodoantipyrine as a diffusible tracer in two strains of conscious normotensive rats (Wistar Kyoto and local Wistar) and in two groups of spontaneously hypertensive stroke-prone rats (SHRSP) with a mean arterial pressure (MAP) below or above 200 mm Hg. In spite of the large differences in arterial pressure, rCBF did not differ significantly between the hypertensive and the normotensive groups in any of the 14 specified brain structures measured. However, rCBF increased asymmetrically within part of the caudate-putamen in two of nine SHRSP with a MAP above 200 mm Hg, indicating a regional drop in the elevated cerebrovascular resistance.

Increase in regional cerebral blood flow following experimental arterial air embolism

1971 ◽  
Vol 34 (5) ◽  
pp. 665-671 ◽  
Author(s):  
Norval M. Simms ◽  
George S. Kush ◽  
Don M. Long ◽  
Merle K. Loken ◽  
Lyle A. French
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Regional Cerebral Blood Flow ◽  
Air Embolism ◽  
Regional Cerebral Blood ◽  
Pathogenetic Mechanism ◽  
Content Type ◽  
Flow Response ◽  
The Mean ◽  
The Right

✓ Acute intracranial hemodynamic alterations consequent to arterial air embolism were studied in the dog using the radioxenon clearance technique. In eight dogs, the mean pre-embolic (control) hemispheric flow was 28.3 ml/100 gm/min. Following the injection of varying amounts of air into the right vertebral artery, there was an augmentation in the measured cerebral blood flow in all animals. Statistical analysis revealed the flow response to be independent of the amounts of air used in these experiments. The mean post-embolic cerebral blood flow was 39.3 ml/100 gm/min, representing a statistically significant increase of 11.0 ml/100 gm/min. Although the post-embolic supernormal flow may be due to the interaction of multiple pathophysiologic factors, air-induced traumatic vasodilatation is advocated as the most important pathogenetic mechanism. Prolonged vasodilatation with loss of autoregulation results in physiological shunting of blood through the affected capillary beds. Alterations in the intracerebral vasculature due to arterial air embolism are compared with studies by other investigators who have observed the effects in extracerebral vessels.

Cerebral venous outflow and arterial microsphere flow with elevated venous pressure

1983 ◽  
Vol 244 (4) ◽  
pp. H505-H512
Author(s):  
E. M. Wagner ◽  
R. J. Traystman
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Mean Arterial Pressure ◽  
Cerebral Autoregulation ◽  
Regional Cerebral Blood Flow ◽  
Venous Pressure ◽  
Regional Cerebral Blood ◽  
Venous Outflow ◽  
Pressure Elevation ◽  
Cerebral Venous Pressure

The cerebral blood flow response to cerebral venous pressure elevation was studied in pentobarbital-anesthetized dogs using the cerebral venous outflow and radiolabeled microsphere techniques. Cerebral venous pressure elevation resulted in a significant reduction in cerebral venous outflow at a pressure of approximately 2.0 mmHg (referenced at the level of the external auditory meatus). At higher pressures, cerebral venous outflow decreased at a rate of 0.5 ml x min-1 x mmHg-1. Mean arterial pressure was 102.0 mmHg, and thus cerebral perfusion pressure (mean arterial pressure minus cerebral venous pressure) was well within the range for cerebral autoregulation. These results were obtained regardless of whether cerebrospinal fluid pressure was allowed to rise concomitantly with cerebral venous pressure (11 dogs) or was maintained at atmospheric pressure (7 dogs). However, simultaneous measurement of cerebral venous outflow and total and regional cerebral blood flow with the radiolabeled microsphere technique with venous pressure elevation (6 dogs) produced discrepant results. As cerebral venous pressure was elevated to approximately 16.0 mmHg, cerebral venous outflow decreased to 40% of control while total and regional cerebral blood flow values remained unchanged, so that regional and cerebral vascular resistances decreased. These results suggest that cerebral venous pressure elevation opens intracranial venous anastomotic channels and diverts blood flow from the measured venous drainage through other drainage sites. In addition, our results suggest that the dominant mechanism of cerebral autoregulation is metabolic, not myogenic.

Regional Cerebral Blood Flow (rCBF) in Migraine During the Interictal Period: Different rCBF Patterns in Patients With and Without Aura

Cephalalgia ◽  
1996 ◽  
Vol 16 (3) ◽  
pp. 161-168 ◽  
Author(s):  
E Facco ◽  
M Munari ◽  
F Baratto ◽  
AU Behr ◽  
A Dal Palu ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Regional Cerebral Blood Flow ◽  
Migraine Without Aura ◽  
Tension Type Headache ◽  
Regional Cerebral Blood ◽  
Healthy Control ◽  
The Mean ◽  
Type Headache ◽  
Age Range

The aim of this study was to evaluate the rCBF (133Xe clearance method) in migrainous patients free from attack. Fifty patients suffering from migraine without aura (group M) and 20 suffering from migraine with aura (group MA) (age range 20-50 years) were submitted to 32 channel rCBF mapping during the interictal period. The rCBF data of patients were compared with those obtained from 60 healthy control subjects (group C) and 21 patients suffering from tension-type headache (group TH). The mean (average of all channels) rCBF values were: group M=70.5 ± 13.7ml/100g/min; group MA=56.6 ± 11.4ml/100g/min; group C=62.3 ± 8.3ml/100g/min; group TH=62.1 ± 8.4ml/100g/min (F=11.93; p<0.001). As expected, patients belonging to group TH had a normal rCBF. The mean rCBF of group M was significantly higher than that of groups C and TH, while in group MA it was significantly lower than in groups C and TH. Group M showed a diffuse hyperemia, while group MA showed rCBF values significantly lower than normal in posterior regions, according to aura. Our results suggest that: (a) the rCBF pattern in migrainous patients is different from that in both controls and TH patients, even during the interictal period; (b) patients suffering from migraine with and without aura are two distinct subpopulations with opposite rCBF deviations.

Sign in / Sign up

Export Citation Format

Share Document