scholarly journals In vivo Binding of Nimodipine in the Brain: I. The Effect of Focal Cerebral Ischemia

1991 ◽  
Vol 11 (5) ◽  
pp. 762-770 ◽  
Author(s):  
Antoine M. Hakim ◽  
Matthew J. Hogan
Keyword(s):  
Cerebral Ischemia ◽  
Striate Cortex ◽  
Focal Cerebral Ischemia ◽  
Brain Structures ◽  
Significant Rise ◽  
Secular Equilibrium ◽  
Control Right ◽  
And Control ◽  
The Brain

We report the regional variation in [3H]nimodipine binding in vivo during focal cerebral ischemia. After intravenous injection, 30 min of circulation of [3H]nimodipine was sufficient to establish a secular equilibrium of distribution in the brain. Rats sustained left middle cerebral and common carotid artery occlusions for 5 min, and 4, 24, and 48 h (n ≥ 6 per group). They were decapitated 30 min after injection of 250 μCi of [3H]nimodipine and their brains were submitted to autoradiography. The concentrations of [3H]nimodipine in plasma and brain structures, corrected for metabolism of nimodipine, were used to calculate the regional volumes of distribution ( V) in the ischemic left (L) and control right (R) hemispheres. Log (VL/VR) was then defined as the group mean of the logarithms of the left-to-right ratio of V of [3H]nimodipine. In the lateral caudate, binding of [3H]nimodipine on the ischemic side was highest within 5 min of occlusion. Log ( VL/ VR) in this region for the combined sham-operated and normal control rats and those after 5 min and 4 and 24 h of ischemia were −0.014 ± 0.025, 0.137 ± 0.056*, −0.201 ± 0.367, and −0.049 ± 0.370 (mean ± SD, *represents p < 0.01 compared with controls). By contrast, in the superior frontal cortex, values for log ( VL/ VR) in the same sequence were −0.016 ± 0.025, 0.028 ± 0.056, 0.284 ± 0.228*, and 0.224 ± 0.069*, thus showing a significant rise in [3H]nimodipine binding only at 4 h. Structures such as the cingulate and striate cortex, sufficiently removed from the ischemic core, showed only small changes in log ( VL/ VR) at all times. Correlating these data with CBF and histologic determinations performed in separate groups of rats, we conclude that [3H]nimodipine binding increases earlier in the more severely ischemic structures than in those with more moderate reductions in perfusion. Furthermore, when binding declines in a region where it was previously increased, infarction is likely. These studies afford new insight into the concept of ischemic penumbra and suggest that this model may allow testing for therapeutic effectiveness.

In vivo Binding of Nimodipine in the Brain: II. Binding Kinetics in Focal Cerebral Ischemia

1991 ◽  
Vol 11 (5) ◽  
pp. 771-778 ◽  
Author(s):  
Matthew J. Hogan ◽  
Albert Gjedde ◽  
Antoine M. Hakim
Keyword(s):  
Cerebral Ischemia ◽  
Calcium Channel ◽  
Focal Cerebral Ischemia ◽  
Binding Capacity ◽  
Affinity Constant ◽  
Binding Characteristics ◽  
In Vivo Binding ◽  
Ischemic Tissue ◽  
The Brain

We report the binding characteristics of [3H]nimodipine to normal and ischemic brain in vivo. We used the 1,4-dihydropyridine, nimodipine, to label the L-type voltage-sensitive calcium channel in focal cerebral ischemia after occlusion of both the middle cerebral and ipsilateral common carotid arteries in rats. Varying concentrations of [3H]nimodipine were infused 3.5 h after the onset of ischemia and circulated for 30 min before the brain was obtained for autoradiography and determination of regional nimodipine content. In separate sets of experiments, the metabolites of nimodipine were determined and the conditions for equilibrium of nimodipine distribution were established. Increased nimodipine uptake was observed in ischemic regions. This increased binding was saturable and specific with an affinity constant, KD, of 0.45 n M and a maximal regional binding capacity, Bmax, ranging from 3.1 to 10.9 pmol/g. Only binding to ischemic tissue was specific and saturable whereas that in nonischemic tissue was nonspecific. In vivo binding of nimodipine may be used to identify cell membrane depolarization and calcium channel activation in focal cerebral ischemia.

scholarly journals Zingiber officinaleMitigates Brain Damage and Improves Memory Impairment in Focal Cerebral Ischemic Rat

2011 ◽  
Vol 2011 ◽  
pp. 1-8 ◽  
Author(s):  
Jintanaporn Wattanathorn ◽  
Jinatta Jittiwat ◽  
Terdthai Tongun ◽  
Supaporn Muchimapura ◽  
Kornkanok Ingkaninan
Keyword(s):  
Cognitive Function ◽  
Cerebral Ischemia ◽  
Brain Damage ◽  
Focal Cerebral Ischemia ◽  
Infarct Volume ◽  
Neuroprotective Effect ◽  
Morris Water Maze Test ◽  
Brain Infarct ◽  
Ginger Rhizome ◽  
The Brain

Cerebral ischemia is known to produce brain damage and related behavioral deficits including memory. Recently, accumulating lines of evidence showed that dietary enrichment with nutritional antioxidants could reduce brain damage and improve cognitive function. In this study, possible protective effect ofZingiber officinale, a medicinal plant reputed for neuroprotective effect against oxidative stress-related brain damage, on brain damage and memory deficit induced by focal cerebral ischemia was elucidated. Male adult Wistar rats were administrated an alcoholic extract of ginger rhizome orally 14 days before and 21 days after the permanent occlusion of right middle cerebral artery (MCAO). Cognitive function assessment was performed at 7, 14, and 21 days after MCAO using the Morris water maze test. The brain infarct volume and density of neurons in hippocampus were also determined. Furthermore, the level of malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) in cerebral cortex, striatum, and hippocampus was also quantified at the end of experiment. The results showed that cognitive function and neurons density in hippocampus of rats receiving ginger rhizome extract were improved while the brain infarct volume was decreased. The cognitive enhancing effect and neuroprotective effect occurred partly via the antioxidant activity of the extract. In conclusion, our study demonstrated the beneficial effect of ginger rhizome to protect against focal cerebral ischemia.

Intact Priming for Novel Perceptual Representations in Amnesia

1997 ◽  
Vol 9 (6) ◽  
pp. 699-713 ◽  
Author(s):  
Stephan B. Hamann ◽  
Larry R. Squire
Keyword(s):  
Recognition Memory ◽  
Declarative Memory ◽  
Brain Structures ◽  
Perceptual Identification ◽  
Single Exposure ◽  
Memory Representations ◽  
Perceptual Representations ◽  
The Creation ◽  
And Control ◽  
The Brain

Recent studies have challenged the notion that priming for ostensibly novel stimuli such as pseudowords (REAB) reflects the creation of new representations. Priming for such stimuli could instead reflect the activation of familiar memory representations that are orthographically similar (READ) and/or the activation of subparts of stimuli (RE, EX, AR), which are familar because they occur commonly in English. We addressed this issue in three experiments that assessed perceptual identification priming and recognition memory for novel and familiar letter strings in amnesic patients and control subjects. Priming for words, pseudowords, and orthographically illegal nonwords was fully intact in the amnesic patients following a single exposure, whereas recognition memory was impaired for the same items. Thus, priming can occur for stimuli that are unlikely to have preexisting representations. Words and pseudowords exhibited twice as much priming as illegal nonwords, suggesting that activation may contribute to priming for words and wordlike stimuli. Additional results showed that priming for illegal nonwords resulted from the formation of new perceptual associations among the component letters of each nonword rather than the activation of individual letter representations. In summary, the results demonstrate that priming following a single exposure can depend on the creation of new perceptual representations and that such priming is independent of the brain structures essential for declarative memory.

scholarly journals Neuroprotection by Brazilian Green Propolis againstIn vitroandIn vivoIschemic Neuronal Damage

2005 ◽  
Vol 2 (2) ◽  
pp. 201-207 ◽  
Author(s):  
Masamitsu Shimazawa ◽  
Satomi Chikamatsu ◽  
Nobutaka Morimoto ◽  
Satoshi Mishima ◽  
Hiroichi Nagai ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Cerebral Ischemia ◽  
Neuronal Damage ◽  
Focal Cerebral Ischemia ◽  
Brain Infarction ◽  
Folk Medicine ◽  
Neuroprotective Function ◽  
Brazilian Green Propolis

We examined whether Brazilian green propolis, a widely used folk medicine, has a neuroprotective functionin vitroand/orin vivo.In vitro, propolis significantly inhibited neurotoxicity induced in neuronally differentiated PC12 cell cultures by either 24 h hydrogen peroxide (H2O2) exposure or 48 h serum deprivation. Regarding the possible underlying mechanism, propolis protected against oxidative stress (lipid peroxidation) in mouse forebrain homogenates and scavenged free radicals [induced by diphenyl-p-picrylhydrazyl (DPPH). In micein vivo, propolis [30 or 100 mg/kg; intraperitoneally administered four times (at 2 days, 1 day and 60 min before, and at 4 h after induction of focal cerebral ischemia by permanent middle cerebral artery occlusion)] reduced brain infarction at 24 h after the occlusion. Thus, a propolis-induced inhibition of oxidative stress may be partly responsible for its neuroprotective function againstin vitrocell death andin vivofocal cerebral ischemia.

scholarly journals Leukocyte-Endothelium Interactions during Permanent Focal Cerebral Ischemia in Mice

2004 ◽  
Vol 24 (6) ◽  
pp. 668-676 ◽  
Author(s):  
Hiroharu Kataoka ◽  
Seong-Woong Kim ◽  
Nikolaus Plesnila
Keyword(s):  
Cerebral Ischemia ◽  
Brain Damage ◽  
Molecular Mechanisms ◽  
Focal Cerebral Ischemia ◽  
Fluorescent Microscopy ◽  
Capillary Density ◽  
Artery Occlusion ◽  
Cerebral Artery Occlusion ◽  
Adherent Leukocytes

The contribution of leukocyte infiltration to brain damage after permanent focal cerebral ischemia and the underlying molecular mechanisms are still unclear. Therefore, the aim of this study was to establish a mouse model for the visualization of leukocytes in the cerebral microcirculation in vivo and to investigate leukocyte-endothelial interaction (LEI) after permanent middle cerebral artery occlusion (MCAO). Sham-operated 129/Sv mice showed physiologic LEI in pial venules as observed by intravital fluorescent microscopy. Permanent focal cerebral ischemia induced a significant increase of LEI predominantly in pial venules. The number of rolling and adherent leukocytes reached 36.5 ± 13.2/100 μm × min and 22.5 ± 7.9/100 μm × min, respectively at 120 minutes after MCAO ( P = 0.016 vs. control). Of note, rolling and adherent leukocytes were also observed in arterioles of ischemic animals (7.3 ± 3.0/100 μm × min rolling and 3.0 ± 3.6/100 μm × min adherent). Capillary density was not different between groups. These results demonstrate that leukocytes accumulate in the brain not only after transient but also after permanent focal cerebral ischemia and may therefore contribute to brain damage after stroke without reperfusion.

Biochemical Effects of Cerebral Ischemia: Relevance To Migraine

Cephalalgia ◽  
1985 ◽  
Vol 5 (2_suppl) ◽  
pp. 35-42 ◽  
Author(s):  
KMA Welch ◽  
JA Helpern ◽  
JR Ewing ◽  
WM Robertson ◽  
G D'Andrea
Keyword(s):  
Energy Metabolism ◽  
Cerebral Ischemia ◽  
Spreading Depression ◽  
Metabolic Depression ◽  
Ischemia And Reperfusion ◽  
Phosphate Metabolism ◽  
Biochemical Effects ◽  
The Brain ◽  
Intracranial Circulation

Although decreased CBF has now been reported during the prodrome of migraine, the cause of the decreased flow is still unknown. It is particularly unclear whether these phenomena are related to vasospasm and “steal” between the extracranial and intracranial circulation or to the spreading depression of Leao and the accompanying metabolic depression. In the present paper, metabolic changes in the brain during ischemia and reperfusion are reviewed and compared with CNS biochemical changes during migraine attack. In addition, the technique of Topical Magnetic Resonance (TMR) as applied to the in vivo study of energy phosphate metabolism in extracranial tissues and brain is described and the potential of this technique to evaluate shifts in energy metabolism and pH in stroke and migraine is discussed.

scholarly journals Increased Aluminum Content in Certain Brain Structures is Correlated with Higher Silicon Concentration in Alcoholic Use Disorder

Molecules ◽  
2019 ◽  
Vol 24 (9) ◽  
pp. 1721 ◽  
Author(s):  
Cezary Grochowski ◽  
Eliza Blicharska ◽  
Jacek Bogucki ◽  
Jędrzej Proch ◽  
Aleksandra Mierzwińska ◽  
...  
Keyword(s):  
Inductively Coupled Plasma ◽  
Optical Emission ◽  
Brain Structures ◽  
Brain Regions ◽  
Protective Role ◽  
Emission Spectrometry ◽  
Inductively Coupled ◽  
Al Content ◽  
And Control ◽  
The Brain

Introduction: Alcohol overuse may be related to increased aluminum (Al) exposure, the brain accumulation of which contributes to dementia. However, some reports indicate that silicon (Si) may have a protective role over Al-induced toxicity. Still, no study has ever explored the brain content of Al and Si in alcoholic use disorder (AUD). Materials and methods: To fill this gap, the present study employed inductively coupled plasma optical emission spectrometry to investigate levels of Al and Si in 10 brain regions and in the liver of AUD patients (n = 31) and control (n = 32) post-mortem. Results: Al content was detected only in AUD patients at mean ± SD total brain content of 1.59 ± 1.19 mg/kg, with the highest levels in the thalamus (4.05 ± 12.7 mg/kg, FTH), inferior longitudinal fasciculus (3.48 ± 9.67 mg/kg, ILF), insula (2.41 ± 4.10 mg/kg) and superior longitudinal fasciculus (1.08 ± 2.30 mg/kg). Si content displayed no difference between AUD and control, except for FTH. Positive inter-region correlations between the content of both elements were identified in the cingulate cortex, hippocampus, and ILF. Conclusions: The findings of this study suggest that AUD patients may potentially be prone to Al-induced neurodegeneration in their brain—although this hypothesis requires further exploration.

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