Abstract TP275: Brain Cell Volume Reductions After Severe Ischemic and Hemorrhagic Strokes in Rat

Stroke ◽  
2020 ◽  
Vol 51 (Suppl_1) ◽  
Author(s):  
Anna C Kalisvaart ◽  
Cassandra M Wilkinson ◽  
Tiffany F Kung ◽  
Yonglie Ma ◽  
Ian R Winship ◽  
...  
Keyword(s):  
Cell Volume ◽  
Cortical Thickness ◽  
Brain Regions ◽  
Volume Density ◽  
Volume Reduction ◽  
Separate Experiment ◽  
Compensatory Mechanisms ◽  
Cellular Density ◽  
Sham Procedure ◽  
Cellular Volume

Background: Raised intracranial pressure (ICP) following severe strokes can impede blood flow to the brain, causing injury or death. There are compensatory mechanisms regulating ICP, but they are often inadequate. Interestingly, our recent observations in intracerebral hemorrhage (ICH) suggest that a volume reduction in remaining brain may serve a compensatory role after large strokes. We observed neurons well outside the hematoma reduce their volume and intercellular space 7 days after the bleed. Here, we tested the hypotheses that this volume reduction would occur sooner in both ischemic and hemorrhagic insults. Methods: Rats received either an ICH via stereotaxic infusion of collagenase or a sham procedure. Euthanasia and perfusion fixation occurred either 1 (N=12), 3 (N=12), or 7 (N=12) days following the ICH. Following histological processing, cellular volume, density, and cortical thickness were assessed with stereological techniques in representative brain regions such as hippocampus, striatum, and primary somatosensory cortex (S1). In a separate experiment, rats received either a middle cerebral artery occlusion (MCAO) via intraluminal suture occlusion (N=8), or a sham procedure (N=7). Rats were euthanized and perfusion fixed 1 day following the MCAO, with brains processed and assessed as described above. Results: After ICH, the decrease in neuronal volume (up to 60%) compared to shams had the largest effect one day following the insult in hippocampal layers CA1 and CA3 (p<0.0001), striatum (p<0.001), and S1 (p<0.05). The largest increase in cellular density occurred one day following the insult in CA1 and CA3 (p<0.0001), and striatum (p<0.001). Cortical thickness was significantly decreased on day 1 (p<0.0001). Following MCAO, cellular volume was significantly decreased compared to shams in areas CA1 (p<0.01) and S1 (p<0.05). Cellular density was significantly increased compared to shams in areas CA1 and S1 (p<0.01), and striatum (p<0.05). Discussion: Our data challenges the assumption that ‘healthy’ brain tissue outside the injured area maintains its volume after stroke. Given the magnitude of cell volume reductions, we posit that this is an important intracranial compliance mechanism invoked after severe strokes.

scholarly journals An update to the Monro–Kellie doctrine to reflect tissue compliance after severe ischemic and hemorrhagic stroke

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Anna C. J. Kalisvaart ◽  
Cassandra M. Wilkinson ◽  
Sherry Gu ◽  
Tiffany F. C. Kung ◽  
Jerome Yager ◽  
...  
Keyword(s):  
Brain Regions ◽  
Artery Occlusion ◽  
Density Increase ◽  
Volume Reduction ◽  
Compensatory Mechanisms ◽  
Severe Stroke ◽  
Injured Area ◽  
Tissue Compliance ◽  
Tissue Shrinkage ◽  
Cerebral Artery Occlusion

AbstractHigh intracranial pressure (ICP) can impede cerebral blood flow resulting in secondary injury or death following severe stroke. Compensatory mechanisms include reduced cerebral blood and cerebrospinal fluid volumes, but these often fail to prevent raised ICP. Serendipitous observations in intracerebral hemorrhage (ICH) suggest that neurons far removed from a hematoma may shrink as an ICP compliance mechanism. Here, we sought to critically test this observation. We tracked the timing of distal tissue shrinkage (e.g. CA1) after collagenase-induced striatal ICH in rat; cell volume and density alterations (42% volume reduction, 34% density increase; p < 0.0001) were highest day one post-stroke, and rebounded over a week across brain regions. Similar effects were seen in the filament model of middle cerebral artery occlusion (22% volume reduction, 22% density increase; p ≤ 0.007), but not with the Vannucci-Rice model of hypoxic-ischemic encephalopathy (2.5% volume increase, 14% density increase; p ≥ 0.05). Concerningly, this ‘tissue compliance’ appears to cause sub-lethal damage, as revealed by electron microscopy after ICH. Our data challenge the long-held assumption that ‘healthy’ brain tissue outside the injured area maintains its volume. Given the magnitude of these effects, we posit that ‘tissue compliance’ is an important mechanism invoked after severe strokes.

scholarly journals Testosterone level, nasal gland volume and Leydig cell morphometry in capybaras (Hydrochoerus hydrochaeris)

2006 ◽  
Vol 58 (6) ◽  
pp. 1086-1091 ◽  
Author(s):  
D.S. Costa ◽  
T.A.R. Paula
Keyword(s):  
Cell Volume ◽  
Leydig Cell ◽  
Gonadosomatic Index ◽  
Serum Testosterone ◽  
Volume Density ◽  
Testosterone Concentration ◽  
Gland Volume ◽  
Testicular Weight ◽  
Hydrochoerus Hydrochaeris ◽  
Proportional Increase

The testosterone levels with nasal gland volume and Leydig cell morphometry in sexually mature capybaras were compared using 10 adult capybaras, aging 28 months. Body and testicular weight were 50kg and 28g, respectively. The gonadosomatic index was 0.11±0.02%, while nasal gland volume was 34.12±13.04ml. Serum testosterone concentration was 25.07±14.73ng/ml. Leydig cell volume density and leydigosomatic index were, respectively, 28.8±8.3% and 0.030±0.007%. Total and individual Leydig cell volumes were 6.88±1.92ml and 2,228.14±272.59x10-12ml, respectively. Leydig cell numbers per testis and per gram of testis were, respectively, 3,079.4±719.9x10(6) and 115.09±31.78x10(6) cells. These results show that increase in serum testosterone concentration is correlated to a proportional increase of nasal gland and Leydig cell volume in capybaras.

scholarly journals Cortical thickness and surface area correlates with cognitive dysfunction among first-episode psychosis patients

2016 ◽  
Vol 46 (10) ◽  
pp. 2145-2155 ◽  
Author(s):  
L. Haring ◽  
A. Müürsepp ◽  
R. Mõttus ◽  
P. Ilves ◽  
K. Koch ◽  
...  
Keyword(s):  
Structure Function ◽  
Surface Area ◽  
Cortical Thickness ◽  
Brain Structure ◽  
Brain Mri ◽  
Brain Regions ◽  
First Episode Psychosis ◽  
First Episode ◽  
Neurocognitive Performance ◽  
Episode Psychosis

BackgroundIn studies using magnetic resonance imaging (MRI), some have reported specific brain structure–function relationships among first-episode psychosis (FEP) patients, but findings are inconsistent. We aimed to localize the brain regions where cortical thickness (CTh) and surface area (cortical area; CA) relate to neurocognition, by performing an MRI on participants and measuring their neurocognitive performance using the Cambridge Neuropsychological Test Automated Battery (CANTAB), in order to investigate any significant differences between FEP patients and control subjects (CS).MethodExploration of potential correlations between specific cognitive functions and brain structure was performed using CANTAB computer-based neurocognitive testing and a vertex-by-vertex whole-brain MRI analysis of 63 FEP patients and 30 CS.ResultsSignificant correlations were found between cortical parameters in the frontal, temporal, cingular and occipital brain regions and performance in set-shifting, working memory manipulation, strategy usage and sustained attention tests. These correlations were significantly dissimilar between FEP patients and CS.ConclusionsSignificant correlations between CTh and CA with neurocognitive performance were localized in brain areas known to be involved in cognition. The results also suggested a disrupted structure–function relationship in FEP patients compared with CS.

scholarly journals Nucleus accumbens cytoarchitecture predicts weight gain in children

2020 ◽  
Vol 117 (43) ◽  
pp. 26977-26984 ◽  
Author(s):  
Kristina M. Rapuano ◽  
Jennifer S. Laurent ◽  
Donald J. Hagler ◽  
Sean N. Hatton ◽  
Wesley K. Thompson ◽  
...  
Keyword(s):  
Weight Gain ◽  
Nucleus Accumbens ◽  
Waist Circumference ◽  
Eating Behaviors ◽  
Saturated Fat ◽  
Brain Regions ◽  
Cellular Density ◽  
Unhealthy Eating ◽  
Early Weight Gain ◽  
Prevalence Of Obesity

The prevalence of obesity in children and adolescents worldwide has quadrupled since 1975 and is a key predictor of obesity later in life. Previous work has consistently observed relationships between macroscale measures of reward-related brain regions (e.g., the nucleus accumbens [NAcc]) and unhealthy eating behaviors and outcomes; however, the mechanisms underlying these associations remain unclear. Recent work has highlighted a potential role of neuroinflammation in the NAcc in animal models of diet-induced obesity. Here, we leverage a diffusion MRI technique, restriction spectrum imaging, to probe the microstructure (cellular density) of subcortical brain regions. More specifically, we test the hypothesis that the cell density of reward-related regions is associated with obesity-related metrics and early weight gain. In a large cohort of nine- and ten-year-olds enrolled in the Adolescent Brain Cognitive Development (ABCD) study, we demonstrate that cellular density in the NAcc is related to individual differences in waist circumference at baseline and is predictive of increases in waist circumference after 1 y. These findings suggest a neurobiological mechanism for pediatric obesity consistent with rodent work showing that high saturated fat diets increase gliosis and neuroinflammation in reward-related brain regions, which in turn lead to further unhealthy eating and obesity.

Effect of isosmotic removal of extracellular Ca2+ and of membrane potential on cell volume in muscle cells

1994 ◽  
Vol 267 (3) ◽  
pp. C768-C775 ◽  
Author(s):  
C. Pena-Rasgado ◽  
K. D. McGruder ◽  
J. C. Summers ◽  
H. Rasgado-Flores
Keyword(s):  
Membrane Potential ◽  
Sarcoplasmic Reticulum ◽  
Cell Volume ◽  
Muscle Cells ◽  
Membrane Depolarization ◽  
Volume Reduction ◽  
Sensitive Volume ◽  
Volume Increase ◽  
Dependent Cell ◽  
In Cells

Isosmotic removal of extracellular Ca2+ (Cao) and changes in membrane potential (Vm) are frequently performed manipulations. Using isolated voltage-clamped barnacle muscle cells, we studied the effect of these manipulations on isosmotic cell volume. Replacing Cao by Mg2+ induced 1) verapamil-sensitive extracellular Na(+)-dependent membrane depolarization, 2) membrane depolarization-dependent cell volume reduction in cells whose sarcoplasmic reticulum (SR) was presumably loaded with Ca2+ [intracellular Ca2+ (Cai)-loaded cells], and 3) cell volume increase in cells whose SR was presumably depleted of Ca2+ (Cai-depleted cells) or in Cai-loaded cells whose Vm was held constant. Membrane depolarization induced 1) volume reduction in Cai-loaded cells or 2) verapamil-sensitive volume increase in Cai-depleted cells. This suggests tha, in Cai-loaded cells, membrane depolarization induces SR Ca2+ release, which in turn promotes volume reduction. Conversely, in Cai-depleted cells, the depolarization activates Na+ influx through a verapamil-sensitive pathway leading to the volume increase. This pathway is also revealed when Cao is removed in either Cai-depleted cells or in cells whose Vm is held constant.

scholarly journals Beyond the average brain: individual differences in social brain development are associated with friendship quality

2020 ◽  
Author(s):  
Andrik I Becht ◽  
Lara M Wierenga ◽  
Kathryn L Mills ◽  
Rosa Meuwese ◽  
Anna van Duijvenvoorde ◽  
...  
Keyword(s):  
Individual Differences ◽  
Brain Development ◽  
Surface Area ◽  
Cortical Thickness ◽  
Friendship Quality ◽  
Brain Regions ◽  
Structural Development ◽  
Quality Development ◽  
Social Brain ◽  
Temporoparietal Junction

Abstract We tested whether adolescents differ from each other in the structural development of the social brain and whether individual differences in social brain development predicted variability in friendship quality development. Adolescents (N = 299, Mage T1 = 13.98 years) were followed across three biannual waves. We analysed self-reported friendship quality with the best friend at T1 and T3, and bilateral measures of surface area and cortical thickness of the medial prefrontal cortex (mPFC), posterior superior temporal sulcus (pSTS), temporoparietal junction (TPJ) and precuneus across all waves. At the group level, growth curve models confirmed non-linear decreases of surface area and cortical thickness in social brain regions. We identified substantial individual differences in levels and change rates of social brain regions, especially for surface area of the mPFC, pSTS and TPJ. Change rates of cortical thickness varied less between persons. Higher levels of mPFC surface area and cortical thickness predicted stronger increases in friendship quality over time. Moreover, faster cortical thinning of mPFC surface area predicted a stronger increase in friendship quality. Higher levels of TPJ cortical thickness predicted lower friendship quality. Together, our results indicate heterogeneity in social brain development and how this variability uniquely predicts friendship quality development.

Sequestration and Possible Maturation of Reticulocytes in the Normal Spleen

1972 ◽  
Vol 50 (5) ◽  
pp. 400-406 ◽  
Author(s):  
S. H. Song ◽  
A. C. Groom
Keyword(s):  
Bone Marrow ◽  
Ringer Solution ◽  
Red Cell ◽  
Cell Compartment ◽  
Daily Production ◽  
Physiological Conditions ◽  
Cellular Density ◽  
Cellular Volume ◽  
Normal Spleen ◽  
Red Pulp

The presence, in the feline spleen, of a slowly exchanging red cell 'compartment' ([Formula: see text] 54 min) has been demonstrated previously. These red cells adhere to reticulum cells and sinus walls in the red pulp and have been shown to be larger in cellular volume and lighter in cellular density than the rest. This suggested that they might be younger cells and we have reported briefly that they contain a high proportion of reticulocytes. Using supravital stains we have measured the percentage of reticulocytes in the outflow from isolated spleens of cats and dogs, perfused with oxygenated Ringer solution. Reticulocyte counts increased from 0.4% to 99% as the perfusion progressed. The results show that the slow compartment consists entirely of reticulocytes. The ratio of reticulocytes to rubricytes in the spleen was found to be 75:1. Therefore the reticulocytes were not produced in the spleen but were accumulated from the circulating blood. The total number of reticulocytes so stored is 1.2 × 1010 cells, equivalent to 1.5 times the daily production in the whole animal. From these data we conclude that reticulocytes released from the bone marrow under physiological conditions are sequestered and matured in the spleen.

scholarly journals “No Pain No Gain”: Evidence from a Parcel-Wise Brain Morphometry Study on the Volitional Quality of Elite Athletes

2020 ◽  
Vol 10 (7) ◽  
pp. 459 ◽  
Author(s):  
Gaoxia Wei ◽  
Ruoguang Si ◽  
Youfa Li ◽  
Ying Yao ◽  
Lizhen Chen ◽  
...  
Keyword(s):  
Cortical Thickness ◽  
Parietal Lobe ◽  
Elite Athletes ◽  
National Level ◽  
Brain Regions ◽  
Sense Of Agency ◽  
Healthy Controls ◽  
Inferior Parietal Lobe ◽  
Brain Morphometry ◽  
Volitional Behavior

Volition is described as a psychological construct with great emphasis on the sense of agency. During volitional behavior, an individual always presents a volitional quality, an intrapersonal trait for dealing with adverse circumstances, which determines the individual’s persistence of action toward their intentions or goals. Elite athletes are a group of experts with superior volitional quality and, thereby, could be regarded as the natural subject pool to investigate this mental trait. The purpose of this study was to examine brain morphometric characteristics associated with volitional quality by using magnetic resonance imaging (MRI) and the Scale of Volitional Quality. We recruited 16 national-level athletes engaged in short track speed skating and 18 healthy controls matched with age and gender. A comparison of a parcel-wise brain anatomical characteristics of the healthy controls with those of the elite athletes revealed three regions with significantly increased cortical thickness in the athlete group. These regions included the left precuneus, the left inferior parietal lobe, and the right superior frontal lobe, which are the core brain regions involved in the sense of agency. The mean cortical thickness of the left inferior parietal lobe was significantly correlated with the independence of volitional quality (a mental trait that characterizes one’s intendency to control his/her own behavior and make decisions by applying internal standards and/or objective criteria). These findings suggest that sports training is an ideal model for better understanding the neural mechanisms of volitional behavior in the human brain.

Isotonic volume reduction associated with cAMP stimulation of 36Cl efflux from jejunal crypt epithelial cells

1994 ◽  
Vol 267 (3) ◽  
pp. G387-G392 ◽  
Author(s):  
R. J. MacLeod ◽  
P. Lembessis ◽  
J. R. Hamilton
Keyword(s):  
Epithelial Cells ◽  
Cell Volume ◽  
Channel Blocker ◽  
Volume Reduction ◽  
K Channel ◽  
Sensitive Volume ◽  
Conductive Pathway ◽  
Camp Stimulation ◽  
Intestinal Crypt Cell ◽  
Crypt Cells

To determine the effect of 8-bromoadenosine 3',5'-cyclic monophosphate (8-BrcAMP) on the isotonic volume of jejunal crypt epithelial cells, we isolated these cells by sequential perfusion using a hyperosmolar Ca(2+)-free solution and measured cell volume electronically. 8-BrcAMP caused rapid shrinkage to a reduced but stable cell volume; this isotonic volume reduction was prevented by either a Cl(-)-channel blocker, anthracene-9-carboxylate (A-9C), or Ba2+, a K(+)-channel blocker. 8-BrcAMP substantially increased the rate of A-9C-sensitive 36Cl efflux from crypt cells; this increased rate of efflux was not influenced by Ba2+ but was abolished by alterations in membrane potential. Following 8-BrcAMP-stimulated isotonic volume reduction, addition of either Ba2+ or A-9C caused the crypt cells to reswell. In contrast, 8-BrcAMP added to enterocytes isolated from the villus compartment did not result in A-9C-sensitive volume reduction or in an increased rate of 36Cl efflux. Our data demonstrate that epithelial cells isolated from jejunal crypt compartments respond directly to cAMP with a rapid volume reduction that is paralleled by an increase in 36Cl efflux through a conductive pathway. Unlike other Cl- secretory epithelial cells, the intestinal crypt cell does not appear to regulate its volume in an isotonic medium after cAMP-induced shrinkage.

scholarly journals Cortical Microstructural Alterations in Mild Cognitive Impairment and Alzheimer’s Disease Dementia

2020 ◽  
Vol 30 (5) ◽  
pp. 2948-2960 ◽  
Author(s):  
Nicholas M Vogt ◽  
Jack F Hunt ◽  
Nagesh Adluru ◽  
Douglas C Dean ◽  
Sterling C Johnson ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Cognitive Impairment ◽  
Mild Cognitive Impairment ◽  
Cortical Thickness ◽  
Gray Matter ◽  
Brain Regions ◽  
Cortical Atrophy ◽  
Microstructural Alterations ◽  
Additional Information

Abstract In Alzheimer’s disease (AD), neurodegenerative processes are ongoing for years prior to the time that cortical atrophy can be reliably detected using conventional neuroimaging techniques. Recent advances in diffusion-weighted imaging have provided new techniques to study neural microstructure, which may provide additional information regarding neurodegeneration. In this study, we used neurite orientation dispersion and density imaging (NODDI), a multi-compartment diffusion model, in order to investigate cortical microstructure along the clinical continuum of mild cognitive impairment (MCI) and AD dementia. Using gray matter-based spatial statistics (GBSS), we demonstrated that neurite density index (NDI) was significantly lower throughout temporal and parietal cortical regions in MCI, while both NDI and orientation dispersion index (ODI) were lower throughout parietal, temporal, and frontal regions in AD dementia. In follow-up ROI analyses comparing microstructure and cortical thickness (derived from T1-weighted MRI) within the same brain regions, differences in NODDI metrics remained, even after controlling for cortical thickness. Moreover, for participants with MCI, gray matter NDI—but not cortical thickness—was lower in temporal, parietal, and posterior cingulate regions. Taken together, our results highlight the utility of NODDI metrics in detecting cortical microstructural degeneration that occurs prior to measurable macrostructural changes and overt clinical dementia.

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