Sympathetic regulation of cerebral blood flow during reflex hypertension

1985 ◽  
Vol 249 (3) ◽  
pp. H672-H680
Author(s):  
P. Lacombe ◽  
M. C. Miller ◽  
J. Seylaz
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Brain Structures ◽  
Systemic Hypertension ◽  
Regional Cerebral Blood ◽  
Acute Hypertension ◽  
Cerebrovascular Autoregulation ◽  
Circulatory Effects ◽  
Sympathetic Regulation ◽  
The Brain

The cerebral circulatory effects of physiological stimulation of the sympathetic nervous system have been examined in the present study. In lightly anesthetized rabbits, reflex sympathetic activation was provoked by bilateral sinus deafferentation and vagotomy. Regional cerebral blood flow (CBF) was measured by the [14C]-ethanol technique and compared in paired brain structures following unilateral superior cervical ganglionectomy. Two subgroups of hypertensive rabbits were statistically distinguished. In the first (19 of 28 rabbits), CBF in the innervated hemisphere was little modified by hypertension but there was a significant side-to-side difference in CBF between the hemispheres. In the second group (9 rabbits) CBF was markedly increased by the systemic hypertension, and little difference was noted between innervated and denervated hemispheres. We demonstrate that, during acute hypertension, the superior cervical system contributes to cerebrovascular autoregulation; this contribution varies according to the brain region studied. In a subgroup of animals, little sympathetic activity could be evidenced, and it is hypothesized that in these rabbits a vasodilatory system was activated that counteracted the myogenic, autoregulatory responses.

Effects of striatal nitric oxide production on regional cerebral blood flow and seizure development in rats exposed to extreme hyperoxia

2015 ◽  
Vol 119 (11) ◽  
pp. 1282-1288 ◽  
Author(s):  
Heath G. Gasier ◽  
Ivan T. Demchenko ◽  
Barry W. Allen ◽  
Claude A. Piantadosi
Keyword(s):  
Nitric Oxide ◽  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Regional Cerebral Blood Flow ◽  
Brain Structures ◽  
Nitric Oxide Production ◽  
Regional Cerebral Blood ◽  
Oxide Production ◽  
Arterial Blood ◽  
The Brain

The endogenous vasodilator and signaling molecule nitric oxide has been implicated in cerebral hyperemia, sympathoexcitation, and seizures induced by hyperbaric oxygen (HBO2) at or above 3 atmospheres absolute (ATA). It is unknown whether these events in the onset of central nervous system oxygen toxicity originate within specific brain structures and whether blood flow is diverted to the brain from peripheral organs with high basal flow, such as the kidney. To explore these questions, total and regional cerebral blood flow (CBF) were measured in brain structures of the central autonomic network in anesthetized rats in HBO2at 6 ATA. Electroencephalogram (EEG) recordings, cardiovascular hemodynamics, and renal blood flow (RBF) were also monitored. As expected, mean arterial blood pressure and total and regional CBF increased preceding EEG spikes while RBF was unaltered. Of the brain structures examined, the earliest rise in CBF occurred in the striatum, suggesting increased neuronal activation. Continuous unilateral or bilateral striatal infusion of the nitric oxide synthase inhibitor Nω-nitro-l-arginine methyl ester attenuated CBF responses in that structure, but global EEG discharges persisted and did not differ from controls. Our novel findings indicate that: 1) cerebral hyperemia in extreme HBO2in rats does not occur at the expense of renal perfusion, highlighting the remarkable autoregulatory capability of the kidney, and 2) in spite of a sentinel increase in striatal blood flow, additional brain structure(s) likely govern the pathogenesis of HBO2-induced seizures because EEG discharge latency was unchanged by local blockade of striatal nitric oxide production and concomitant hyperemia.

Vorläufige Ergebnisse von 99mTc-HMPAO-SPECT-Untersuchungen bei endogenen Psychosen

1989 ◽  
Vol 28 (03) ◽  
pp. 88-91
Author(s):  
J. Schröder ◽  
H. Henningsen ◽  
H. Sauer ◽  
P. Georgi ◽  
K.-R. Wilhelm
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Regional Cerebral Blood Flow ◽  
Regions Of Interest ◽  
Post Mortem ◽  
Regional Cerebral Blood ◽  
Hmpao Spect ◽  
Endogenous Psychoses ◽  
The Brain ◽  
99Mtc Hmpao

18 psychopharmacologically treated patients (7 schizophrenics, 5 schizoaffectives, 6 depressives) were studied using 99mTc-HMPAO-SPECT of the brain. The regional cerebral blood flow was measured in three transversal sections (infra-/supraventricular, ventricular) within 6 regions of interest (ROI) respectively (one frontal, one parietal and one occipital in each hemisphere). Corresponding ROIs of the same section in each hemisphere were compared. In the schizophrenics there was a significantly reduced perfusion in the left frontal region of the infraventricular and ventricular section (p < 0.02) compared with the data of the depressives. The schizoaffectives took an intermediate place. Since the patients were treated with psychopharmaca, the result must be interpreted cautiously. However, our findings seem to be in accordance with post-mortem-, CT- and PET-studies presented in the literature. Our results suggest that 99mTc-HMPAO-SPECT may be helpful in finding cerebral abnormalities in endogenous psychoses.

scholarly journals Motor Improvement-Related Regional Cerebral Blood Flow Changes in Parkinson’s Disease in Response to Antiparkinsonian Drugs

2019 ◽  
Vol 2019 ◽  
pp. 1-8
Author(s):  
Soutarou Taguchi ◽  
Nachi Tanabe ◽  
Jun-ichi Niwa ◽  
Manabu Doyu
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Regional Cerebral Blood Flow ◽  
Brain Structures ◽  
Regional Cerebral Blood ◽  
Motor Improvement ◽  
Antiparkinsonian Drugs ◽  
Deep Brain

Little is known about the relationship between regional cerebral blood flow (rCBF) change and clinical improvement in patients with Parkinson’s disease (PD). Single-photon emission computed tomography (SPECT) measurement of cerebral blood flow allows evaluation of temporal changes in brain function, and using SPECT, we aimed to identify motor improvement-related rCBF changes in response to the administration of antiparkinsonian drugs. Thirty PD patients (16 without dementia; 14 with dementia) were scanned with technetium-99m labeled ethyl cysteinate dimer SPECT and were rated with the Movement Disorder Society-Unified Parkinson’s Disease Rating Scale part III, both before and after a single administration of antiparkinsonian drugs. The SPECT data were processed using Statistical Parametric Mapping 2, the easy Z-score Imaging System, and voxel-based Stereotactic Extraction Estimation. The rCBF responses in the deep brain structures after administration of antiparkinsonian drugs tended to be larger than those in cortical areas. Among these deep brain structures, the rCBF increases in the substantia nigra (SN), lateral geniculate (LG) body, and medial geniculate (MG) body correlated with drug efficacy (p<0.05, respectively). A subgroup analysis revealed that the motor improvement-related rCBF change in the MG was statistically significant, irrespective of cognitive function, but the significant changes in the LG and SN were not found in subjects with dementia. In conclusion, our SPECT study clearly exhibited drug-driven rCBF changes in PD patients, and we newly identified motor improvement-related rCBF changes in the LG and MG. These results suggest that rCBF changes in these regions could be considered as candidates for clinical indicators for objective evaluation of disease progression. Furthermore, functional studies focusing on the LG and MG, especially in relation to therapies using audio-visual stimuli, may bring some new clues to explain the pathophysiology of PD.

scholarly journals Improvement in Local Cerebral Blood Flow Measurement in Gerbil Brains by Prevention of Postmortem Diffusion of [14C]Iodoantipyrine

1992 ◽  
Vol 12 (2) ◽  
pp. 296-300 ◽  
Author(s):  
Takao Hatakeyama ◽  
Saburo Sakaki ◽  
Ko Nakamura ◽  
Shigeru Furuta ◽  
Kenzou Matsuoka
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Liquid Nitrogen ◽  
Brain Structures ◽  
Drying Time ◽  
Modified Method ◽  
Hot Air ◽  
Conventional Drying ◽  
Postmortem Brains ◽  
The Brain

Postmortem diffusion of [14C]iodoantipyrine, which distorts the image of cerebral blood flow, can occur in at least three steps; from decapitation until the brain is frozen, while frozen sections on coverslips are thawed, and when dried sections are applied to x-ray film. In the present study, the first two steps were modified to reduce the time during which brain tissue was wet. When the brains of gerbils were taken out of the skulls and immersed in chilled isopentane (–45°C), 90–95 s elapsed between decapitation until the brain tissues were frozen. However, immersion of whole heads in liquid nitrogen after decapitation decreased the time to 25 s. The autoradiograms had better contrast after the freezing procedure with liquid nitrogen than after that with chilled isopentane. The drying time of the thawed sections was markedly reduced by blowing hot air across the sections on a hot plate, and this resulted in clearer images on autoradiograms. In most of the tissues with values of cerebral blood flow over 100 ml 100 g−1 min−1 as measured using the conventional drying method, the corresponding values were higher if the modified method was used. In contrast, in tissues with values less than 100 ml 100 g−1 min−1, the corresponding values were lower. Moreover, the differences between flows in adjacent small brain structures were less clear if the sections were dried by the conventional method. Reducing the time during which postmortem brains or sections are wet can help prevent [14C]iodoantipyrine diffusion artifacts.

Personality and Regional Cerebral Blood Flow

1984 ◽  
Vol 144 (5) ◽  
pp. 529-532 ◽  
Author(s):  
Roy J. Mathew ◽  
Maxine L. Weinman ◽  
Deborah L. Barr
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Brain Function ◽  
Regional Cerebral Blood Flow ◽  
Cortical Arousal ◽  
Regional Cerebral Blood ◽  
Capillary Perfusion ◽  
Brain Capillary ◽  
Eysenck Personality Inventory ◽  
The Brain

SummaryThe extraversion–introversion dimension of personality is believed to have an inverse relationship with cortical arousal. Brain capillary perfusion is a well established index of brain function and arousal. Regional cerebral blood flow was measured in 51 right-handed females whose personality structure was examined with the Eysenck Personality Inventory (EPI). Significant inverse correlations were found between the brain blood flow and the extraversion–introversion score of EPI.

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.

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