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Thumburu KK, Taneja S, Vasishta RK, Dhiman RK. Neuropathology of acute liver failure. Neurochem Int 2011; 60:672-5. [PMID: 22198438 DOI: 10.1016/j.neuint.2011.10.013] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2011] [Revised: 10/14/2011] [Accepted: 10/26/2011] [Indexed: 12/22/2022]
Abstract
Cerebral edema has been identified in all forms of liver disease and is closely related to the development of hepatic encephalopathy. Cerebral edema is most readily recognized in acute liver failure (ALF), while the main cause of death in patients with ALF is multi-organ failure; brain herniation as a result of intracranial hypertension does remain a major cause of mortality. The mechanisms responsible for cerebral edema in ALF suggest both cytotoxic and vasogenic injury. This article reviews the gross and ultrastructural changes associated with cerebral edema in ALF. The primary cause of cerebral edema is associated with astrocyte swelling, mainly perivascular edema and ammonia still remains the primary neurotoxin involved in its pathogenesis. The astrocytic changes were confined to the gray matter. The other organelles involved in the pathogenesis of ALF include mitochondria, basement membrane, pericytes, microglial cells, blood-brain barrier (BBB) etc. Discrete neuronal changes have recently been reported. Recent studies in animal and humans have demonstrated the microglial changes which have the potential to cause neuronal dysfunction in ALF. The alterations in BBB still remain unclear though few studies have showed disruption of tight junction proteins indicating the involvement of BBB in cellular swelling.
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Affiliation(s)
- Kiran K Thumburu
- Department of Hepatology, Postgraduate Institute of Medical Education & Research, Chandigarh 160012, India
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2
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Short Period of Early Reperfusion Aggravates Blood–Brain Barrier Dysfunction During Permanent Focal Ischemia in Rats. Transl Stroke Res 2010; 2:67-71. [DOI: 10.1007/s12975-010-0042-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2010] [Revised: 08/22/2010] [Accepted: 08/23/2010] [Indexed: 10/19/2022]
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3
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Xiao F, Pardue S, Nash T, Arnold TC, Alexander JS, Carden DL, Turnage R, Jawahar A, Conrad SA. Cell column chromatography: a new research tool to quantify cerebral cell volume changes following chemically-induced anoxia/re-oxygenation. ACTA NEUROCHIRURGICA. SUPPLEMENT 2005; 95:411-4. [PMID: 16463892 DOI: 10.1007/3-211-32318-x_84] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
OBJECTIVE The roles of individual types of cerebral cells in contributing to brain edema are undefined. The objective of this study was to determine the role of cerebral cell-column chromatography in quantifying cell volumes of individual cerebral cell lines, under chemically-induced anoxia/re-oxygenation (A/R). METHODS Cerebral endothelial cells (4 experiments) or type II astrocytes (4 experiments) were cultured to confluence on microcarrier beads. A chromatographic cell-column of 1.5 cm height was filled with non-treated cell-covered beads. The column was perfused at 1 ml/min with a balanced perfusate for one hour (Baseline). The perfusate was then switched to that containing 5 mM thioglycolic acid for one hour (Anoxia). Then the column was perfused with the normal perfusate for another two hours (Re-oxygenation). The total free space in the column, reversely reflecting cell volumes, was determined by averaged transit time (TTa) of a non-permeable flow tracer blue dextran. Decreased TTa means that cells swell, and vice versa. RESULTS TTa in endothelial cell columns increased with a peak at 60 minutes of re-oxygenation. TTa in astrocyte columns decreased with a nadir at 30 minutes of re-oxygenation. CONCLUSION Cell column chromatography can be used to determine the cerebral cell volume changes following chemically-induced anoxia/re-oxygenation.
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Affiliation(s)
- F Xiao
- Department of Emergency Medicine, Louisiana State University Health Science Center, Shreveport 71130, USA.
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4
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Hernández F, Martínez AM, Piedra D, Catalán RE. Endothelin inhibits histamine-induced cyclic AMP accumulation in bovine brain vessels. Microvasc Res 2000; 60:49-54. [PMID: 10873514 DOI: 10.1006/mvre.2000.2241] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We have studied whether endothelin isopeptides have any effects on histamine-induced cyclic AMP in [(3)H]adenine-prelabeled brain vessels isolated from bovine brain. Basal levels of [(3)H]cyclic AMP were enhanced by histamine in a concentration-dependent manner (EC(50) = 1.1 +/- 0.3 microM). Endothelin-1 inhibited histamine-elicited [(3)H]cyclic AMP generation with an IC(50) value of 3 +/- 2.5 nM. Sarafotoxin 6c, an ET-B receptor agonist, had no effect. ET-1 inhibition of histamine-induced [(3)H]cyclic AMP was reversed by the ET-A receptor antagonist BQ-123 while the ET-B receptor antagonist BQ-788 had no effect. The levels of [(3)H]cyclic AMP induced by isoprenaline were not altered by endothelin-1. Taken together, these results show that endothelins modulate the actions of histamine on the blood-brain barrier, probably by type A endothelin receptors.
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Affiliation(s)
- F Hernández
- Departamento de Biología Molecular, Universidad Autónoma de Madrid, Spain
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5
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Isaacks RE, Bender AS, Kim CY, Shi YF, Norenberg MD. Effect of ammonia and methionine sulfoximine on myo-inositol transport in cultured astrocytes. Neurochem Res 1999; 24:51-9. [PMID: 9973237 DOI: 10.1023/a:1020928029845] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Ammonia causes astrocyte swelling which is abrogated by methionine sulfoximine (MSO). Since myo-inositol is an important osmolyte, we investigated the effects of ammonia and MSO on myoinositol flux in cultured astrocytes for periods up to 72 hours. Uptake of myo-inositol was significantly decreased by 26.7 (P < 0.05) and 39.3 (P < 0.006) percent after 48 hours of exposure to 5 or 10 mM ammonia, respectively. The maximum rate of uptake was 14.0+/-0.5 nmol/hour/mg protein which was reduced to 7.45+/-0.27 and 7.02+/-0.57 nmoles/hour/mg protein by 5 or 10 mM ammonia, respectively. The Kms by Michaelis-Menten equation for the control, and in the presence of 5, or 10 mM ammonia were 32.5+/-4.52, 44.4+/-5.82, and 39.3+/-7.0 microM, respectively. Kms by Hanes-Woolf plot for the control, 5, or 10 mM ammonia were 25, 45, and 40 microM, respectively. Treatment of astrocytes with either 5 or 10 mM NH4Cl for 6 hours caused a decrease in myo-inositol content by 66% and 58%, respectively. MSO (3 mM) partially diminished the ammonia-induced inhibition of myo-inositol uptake and decreased myo-inositol content by 31% after 24 hours. Additionally, ammonia increased myo-inositol efflux briefly through the fast efflux component but had little effect on myo-inositol efflux through the slow efflux component of astrocytes exposed to ammonia for up to 72 hours. Predominantly decreased myo-inositol influx coupled with brief efflux through the fast component may represent an adaptive response to diminish the extent of ammonia-induced astrocyte swelling.
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Affiliation(s)
- R E Isaacks
- Research Laboratories, Veterans Affairs Medical Center, Miami, FL 33125, USA
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6
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Sharma HS, Westman J, Nyberg F. Pathophysiology of brain edema and cell changes following hyperthermic brain injury. PROGRESS IN BRAIN RESEARCH 1998; 115:351-412. [PMID: 9632943 DOI: 10.1016/s0079-6123(08)62043-9] [Citation(s) in RCA: 114] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- H S Sharma
- Department of Anatomy, Uppsala University, Sweden.
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7
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Schwab M, Bauer R, Zwiener U. Physiological effects and brain protection by hypothermia and cerebrolysin after moderate forebrain ischemia in rats. EXPERIMENTAL AND TOXICOLOGIC PATHOLOGY : OFFICIAL JOURNAL OF THE GESELLSCHAFT FUR TOXIKOLOGISCHE PATHOLOGIE 1997; 49:105-16. [PMID: 9085084 DOI: 10.1016/s0940-2993(97)80078-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The "therapeutic window" of neuroprotective intervention due to hypoxic-ischemic brain injuries are initial disturbances of the neuronal function in regions of only moderate decrease of local cerebral blood flow (ICBF). Because of limited effects of single therapeutic principles therapeutic combinations should be tested. Neuroprotective effects of mild hypothermia and the nootropic drug Cerebrolysin (Cerebrolysin, EBEWE, Austria) on ICBF and development of brain edema were used. Four groups of adult Wistar rats (untreated and Cerebrolysin treated animals with 35 degrees C and 37 degrees C rectal temperature) were subjected to moderate forebrain ischemia by permanent bilateral carotid artery ligation for 6 h. The ICBF was measured continuously in the frontal and the occipital cortex by a 2-channel Laser Doppler flowmeter. The ECoG was derived from 4 ECoG leads above the frontal and occipital cortex and quantified by spectral analysis. Six hours after the onset of ischemia, the function of the blood-brain barrier to proteins was determined by staining with Evans Blue, the animals were sacrificed and the brain water content was estimated by gravimetry. Permanent bilateral carotid artery ligation led to an abrupt ICBF reduction to between 40-50% of baseline levels. Within a few minutes, however, the ICBF increased again to 50-80% of the baseline. The reduced spectral band power of the ECoG was correlated with the decreased ICBF values (p < 0.05) that indirectly indicated changes in the energy state of the neurons (p < 0.05). Changes in the ECoG appeared only with a delay of approximately 4 sec after the onset of ICBF reduction. Six hours after the onset of ischemia, a cytotoxic brain edema was shown in the frontoparietal cortex and hippocampus. Reducing the temperature by 2 degrees C diminished the decrease in ICBF between 10 min and 2 h after the onset of ischemia (p < 0.05). This effect was noted in the frontal but not in the occipital cortex. Furthermore, mild hypothermia prevented the loss of ECoG spectral power in the beta, alpha and theta bands (p < 0.05) as well as the development of cytotoxic brain edema. Cerebrolysin prevented the development of brain edema, too, both under normo- and hypothermic conditions. The ICBF was restored to higher levels in the occipital cortex in comparison both to the normothermic Cerebrolysin treated and hypothermic untreated rats (p < 0.05). This effect of Cerebrolysin was associated with only slight changes in ECoG, indicating that the neuronal activity state and the energy supply was obviously not decisively influenced. In conclusion, moderate ICBF reduction in rats to about 50-80% of baseline values was detectable in the ECoG by using spectral analysis. This reduction led to the development of cytotoxic brain edema in rats within 6 h. Thus, hypothermia prevents the development of cytotoxic brain edema. Cerebrolysin enhanced the effects of hypothermia on ICBF reduction and on the development of brain edema.
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Affiliation(s)
- M Schwab
- Institute of Pathophysiology, Friedrich Schiller University Jena, Germany.
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8
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Huszti Z, Deli MA, Joó F. Carrier-mediated uptake and release of histamine by cultured rat cerebral endothelial cells. Neurosci Lett 1995; 184:185-8. [PMID: 7536316 DOI: 10.1016/0304-3940(94)11202-t] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The present study demonstrates that histamine could be taken up by and released from endothelial cells of brain capillaries. Incubation of cultured endothelial cells, with low (0.01-0.50 microM) concentrations of [3H]histamine, resulted in a rapid uptake of the amine. The uptake was saturable, Na(+)-dependent and yielded an apparent Km 0.3 +/- 0.02 microM and a Vmax 4.6 +/- 0.04 pmol/mg protein per min. After a 10-min incubation in a histamine-free medium, about 65% of [3H]histamine was released from the cells. Na(+)-deprivation and high K+, as well as the treatment of the cells with ouabain affected the release, resulting in significantly higher rates of the efflux. The ability of cerebral endothelial cells to take up histamine from both luminal and abluminal sides but to release it mainly luminally, may function as an important mechanism to protect the neural tissue from the harmful effects of this endogenous mediator of inflammation.
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Affiliation(s)
- Z Huszti
- Department of Pharmacodynamics, Semmelweis University of Medicine, Budapest, Hungary
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9
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Abstract
Astrocytes exposed to hypoosmotic stress swell and subsequently reduce their size to almost their original volume, a phenomenon called regulatory volume decrease (RVD). We found that during hypoosmotic swelling there was a twofold increase in phosphatidylinositol (PI) hydrolysis. This increase was inhibited by the phospholipase C inhibitor, U-73122 (10 microM). Inhibition of PI hydrolysis resulted in blockage of RVD. We also examined whether agents that stimulate PI hydrolysis would enhance RVD. These agents significantly accelerated RVD. The rank order of potency was endothelin (20 nM) > or = norepinephrine (100 microM) > endothelin-3 (7 nM) > thrombin (1 U/ml) > or = ATP (500 microM) > bradykinin (20 microM) > or = carbachol (500 microM), as indicated by RVD rate constants. The extent of PI hydrolysis induced by these agents at the beginning of RVD exhibited a logarithmic relationship with the magnitude of RVD enhancement. Also, there was a linear relationship between the rate of PI hydrolysis and RVD rate constants. Our results suggest that stimulated PI hydrolysis is involved in the regulation of cell volume in astrocytes.
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Affiliation(s)
- A S Bender
- Department of Pathology, University of Miami School of Medicine, FL 33101
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10
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Abstract
We report an infant with congenital nephrotic syndrome who showed clinical and radiological evidence of cerebral oedema, which resolved during prolonged intravenous albumin therapy. The cerebral oedema in this case can possibly be attributed to the relative immaturity of the blood-brain barrier in early infancy.
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Affiliation(s)
- M Weintraub
- Division of Paediatric Nephrology, Shaare Zedek Medical Centre, Hebrew University-Hadassah Medical School, Jerusalem, Israel
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11
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Kato M, Hughes RD, Keays RT, Williams R. Electron microscopic study of brain capillaries in cerebral edema from fulminant hepatic failure. Hepatology 1992; 15:1060-6. [PMID: 1592344 DOI: 10.1002/hep.1840150615] [Citation(s) in RCA: 150] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Cerebral edema is a serious complication of the encephalopathy in fulminant hepatic failure. It is a major cause of death. The mechanisms responsible for its formation are unclear, and the aim of this study was to investigate the ultrastructural appearance of brain capillaries by scanning electron microscopy. Samples of cerebral cortex were obtained immediately after death from nine patients with fulminant hepatic failure (seven cases due to acetaminophen overdose, one caused by hepatitis B and one caused by non-A, non-B hepatitis) by needle biopsy at the site of insertion of an extradural pressure transducer to monitor intracranial pressure. The intercellular tight junctions between capillary endothelial cells were intact. The endothelial cells were swollen, with increased numbers of vesicles and vacuoles. The basement membranes were enlarged and vacuolized and the pericytes had increased numbers of vesicles and vacuoles, indicative of passage of fluid by this route. Marked intracellular swelling of the perivascular astroglial foot processes was present. Thus mainly cytotoxic mechanisms, with cellular swelling, and to a lesser extent vasogenic mechanisms, with altered blood-brain barrier permeability, appear to be involved in the cerebral edema of fulminant hepatic failure.
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Affiliation(s)
- M Kato
- Institute of Liver Studies, King's College Hospital, London, United Kingdom
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12
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Kálmán J, Gecse A, Farkas T, Joó F, Telegdy G, Lajtha A. Dietary manipulation with high marine fish oil intake of fatty acid composition and arachidonic acid metabolism in rat cerebral microvessels. Neurochem Res 1992; 17:167-72. [PMID: 1531701 DOI: 10.1007/bf00966795] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Male weanling Wistar rats were maintained on one of two semisynthetic diets, differing only in the type of oil used: (i) 10% by weight marine fish oil (MFO group) containing 20% eicosapentaenoic acid (EPA) and 17% docosahexaenoic acid (DHA), or (ii) 10% by weight sunflower oil (SFO group). The control group was kept on standard diet for 4 weeks. Blood-free microvessels were isolated from brain cortex by a rapid micromethod, and their fatty acid composition was determined by gas chromatography. It was found that the proportion of n-3 fatty acids (including EPA and DHA) increased significantly in the microvessels of the MFO group, accompanied by a decrease of the n-6 fatty acid series. The changes in fatty acid composition of endothelial cells were not significant in the SFO group in comparison to the control. The amounts of lipoxygenase and cyclooxygenase metabolites were determined. Dietary fish oil decreased the percentage of total products of arachidonate by 50%, while the SFO diet had no effect on it. The amount of lipoxygenase products in the MFO group decreased significantly from 16931 +/- 3131 dpm to 6399 +/- 357 dpm/300 mg wet weight of brain. Significantly less PGF-1 alpha, PGF-2 alpha and 12-hydroxyheptadecatrienoic acid (HHT) were found in the capillaries of MFO treated animals, in comparison to the SFO group. The ratios of vasoconstrictor and vasodilator metabolites of arachidonate cascade were not modified by the diets. Our results suggest that fish oil diet reduces the arachidonate cascade in cerebral microvessels. This effect may explain for the efficiency of n-3 fatty acids in vascular diseases.
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Affiliation(s)
- J Kálmán
- Department of Neurology and Psychiatry, Albert Szent-Györgyi Medical University, Szeged, Hungary
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13
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Greenwood J. Astrocytes, cerebral endothelium, and cell culture. The pursuit of an in vitro blood-brain barrier. Ann N Y Acad Sci 1991; 633:426-31. [PMID: 1789564 DOI: 10.1111/j.1749-6632.1991.tb15632.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- J Greenwood
- Department of Clinical Science, Institute of Ophthalmology, London, UK
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14
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Abstract
The functional status of the blood-brain barrier (BBB) must be taken into account when designing and interpreting brain imaging techniques. The integrity of the BBB is affected in many diseases of the brain, with the potential involvement of a number of different but poorly understood cellular mechanisms. Factors known to disrupt the BBB experimentally include arachidonic acid and the eicosanoids, bradykinin, histamine and free radicals. These active compounds, released in pathological tissue, may alter cytosolic calcium levels and induce second messenger systems leading to an alteration in BBB permeability. Extravasation of plasma proteins may occur via disrupted tight junctions, stimulation of fluid-phase vesicular transport or the formation of transcellular pores or channels.
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Affiliation(s)
- J Greenwood
- Department of Clinical Science, Institute of Ophthalmology, London, UK
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15
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Sharma HS, Olsson Y, Dey PK. Changes in blood-brain barrier and cerebral blood flow following elevation of circulating serotonin level in anesthetized rats. Brain Res 1990; 517:215-23. [PMID: 2375992 DOI: 10.1016/0006-8993(90)91029-g] [Citation(s) in RCA: 119] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Plasma serotonin (5-HT) was elevated by an intravenous infusion of this amine into urethane-anaesthetized rats and the concentration approximated that present in various neurological diseases and mental abnormalities. An infusion of 10 micrograms per kg body weight for 10 min significantly increased blood-brain barrier (BBB) permeability to Evans blue and 131I-sodium measured in whole brain. Regional BBB determinations with labelled 131I-sodium showed that the permeability to this compound was increased in the cerebral cortex, hippocampus, caudate nucleus, hypothalamus, colliculus and the cerebellum but not in the pons and the medulla oblongata. Regional blood flow was reduced in the same parts which showed BBB abnormality tested with 125I-labeled microspheres. Pretreatment with cyproheptadine, a 5-HT2 receptor antagonist, prevented the BBB increase and the regional blood flow was near normal values. Similar effects were obtained with indomethacin, a prostaglandin synthesis inhibitor. Vinblastine, known to influence vesicular transport, eliminated extravasation of the tracers but the regional blood flow remained depressed. A hypothesis is put forward that serotonin after binding to its receptor in the cerebral vessels stimulates prostaglandin which either directly or by means of cyclic adenosine monophosphate causes an increased vesicular transport across the endothelial cells and thus an extravasation of tracer substances in the brain. Obviously, this form of exudation can be influenced by pharmacological means.
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Affiliation(s)
- H S Sharma
- Laboratory of Neuropathology, Institute of Pathology, University Hospital, Uppsala, Sweden
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16
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Olsson Y, Sharma HS, Pettersson CA. Effects of p-chlorophenylalanine on microvascular permeability changes in spinal cord trauma. An experimental study in the rat using 131I-sodium and lanthanum tracers. Acta Neuropathol 1990; 79:595-603. [PMID: 2141746 DOI: 10.1007/bf00294236] [Citation(s) in RCA: 63] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The possibility that serotonin can take part in the initiation of the increased microvascular permeability occurring in a spinal cord trauma was investigated in a rat model with 131I-sodium and lanthanum as tracers. We influenced the serotonin content in the tissue pharmacologically by treating animals with a serotonin synthesis inhibitor, p-chlorophenylalanine (p-CPA), before the production of the injury and compared the results with injured, untreated controls. A small incision was made in the dorsal horn of the lower thoracic cord. It caused a progressive extravasation of 131I-sodium in the damaged segment, measured after 1, 2 and 5 h. Rostral and caudal segments also showed a significant but lower accumulation of 131I-sodium. Lanthanum added to the fixative was used as an ionic tracer detectable by electron microscopy. The endothelial cells of microvessels removed from the perifocal region after 5 h showed a marked increase in the number of lanthanum-filled vesicles. Many endothelial cells had a diffuse penetration of the tracer into the cytoplasm and the basement membrane. However, the tight junctions usually remained closed to lanthanum. Pretreatment with p-CPA markedly reduced the extravasation of 131I-sodium measured at 5 h in the traumatized cord. At the cellular level, the endothelial vesicles filled with lanthanum approached the condition of uninjured animals. The diffuse infiltration of lanthanum into endothelial cells and its spread into the basement membrane of the vascular wall were usually absent. Our results indicate that serotonin plays a role in the initiation of the increased microvascular permeability which occurs in spinal cord injuries.
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Affiliation(s)
- Y Olsson
- Institute of Pathology, University Hospital, Uppsala, Sweden
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Dux E, Ismail M, Szerdahelyi P, Joó F, Dux L, Koltai M, Draskóczy M. Dexamethasone treatment attenuates the development of ischaemic brain oedema in gerbils. Neuroscience 1990; 34:203-7. [PMID: 2158006 DOI: 10.1016/0306-4522(90)90313-s] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Transient global forebrain ischaemia was produced in Mongolian gerbils by occluding both common carotid arteries for 10 min followed by 48 h recirculation. Dexamethasone, 5 mg/kg i.p., was given 5 h before the occlusion and every 12 h thereafter. After occlusion an increase in water, sodium and calcium content was found in the parietal cortex and hippocampus, while the concentration of potassium decreased. Exudation of plasma albumin was not found in the brain. The activity of Na+, K(+)-ATPase decreased in the hippocampus. Morphological signs of cerebral oedema were also observed, both in the CA1 region of the hippocampus and in the cortex. Dexamethasone treatment prevented the accumulation of water, sodium and calcium in the ischaemic brain. It also attenuated the oedematous morphological changes of the blood-brain barrier. Thus dexamethasone treatment may also have therapeutic relevance in the acute, high-risk phase of patients suffering from repetitive, transitoric cerebral ischaemia.
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Affiliation(s)
- E Dux
- Institute of Biophysics, Hungarian Academy of Sciences, Szeged
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18
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Mohanty S, Dey PK, Sharma HS, Singh S, Chansouria JP, Olsson Y. Role of histamine in traumatic brain edema. An experimental study in the rat. J Neurol Sci 1989; 90:87-97. [PMID: 2723676 DOI: 10.1016/0022-510x(89)90048-8] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The possibility that histamine plays a role in the formation of traumatic brain edema was investigated in the rat. A 3 mm deep and 3 mm long stab injury was performed in the right parietal cortex under urethane anaesthesia. The brain water content and histamine levels in plasma and brain were measured at the end of 1, 2 and 5 h periods after trauma. There was a 3.46% increase in brain water content in the traumatized hemisphere from the value in the control group at 5 h. The histamine content was increased by 107% in plasma and 51% in the traumatized brain hemisphere from the control value at this time period. The increased brain water content as well as the elevated plasma and brain histamine levels were prevented by prior treatment with the histamine H2-receptor antagonist cimetidine. Mepyramine (a histamine H1-receptor antagonist) failed to reduce the increased brain water content and the histamine levels in plasma and brain remained high. The results strongly indicate that histamine has a role in the formation of early traumatic brain edema and that this reaction can be influenced by pharmacological procedures.
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Affiliation(s)
- S Mohanty
- Section of Neurosurgery, Banaras Hindu University, Varanasi, India
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19
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Temesvári P, Kovács J. Selective opening of the blood-brain barrier in newborn piglets with experimental pneumothorax. Neurosci Lett 1988; 93:38-43. [PMID: 3211368 DOI: 10.1016/0304-3940(88)90009-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Pial-arachnoidal microvessels (40-210 micron) were studied by fluorescent microscopy in anaesthetized, immobilized and ventilated newborn piglets in the course of bilateral experimental pneumothorax (BEP; n = 10) using the open cranial window technique. Na+-fluorescein and fluorescein isothiocyanate (FITC)-dextran (mol.wt. 40,000 and 70,000 Da) administered i.v. served as blood-brain barrier (BBB) indicators. After gradual exhaustion of compensatory mechanisms a critical phase, characterized by severe acidosis, bradycardia, arterial hypotension following hypertension and arterial hypoxaemia ensued, with vasoconstriction following vasodilation. Moreover, progressive circulation disturbances, sludging and microthrombi formation occurred in small venules. Concomitantly, diffuse BBB opening for Na+-fluorescein ensued in all piglets with BEP as shown by extended fluorescence in the brain tissue around the small venules (less than 80 micron); never observed for FITC-dextran and in the control animals (n = 4) without BEP. In the acute phase of pneumothorax a selective opening of the BBB should be considered.
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Affiliation(s)
- P Temesvári
- Department of Pediatrics, Szent-Györgyi Albert University Medical School, Szeged, Hungary
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20
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Vorbrodt AW. Ultrastructural cytochemistry of blood-brain barrier endothelia. PROGRESS IN HISTOCHEMISTRY AND CYTOCHEMISTRY 1988; 18:1-99. [PMID: 3055069 DOI: 10.1016/s0079-6336(88)80001-9] [Citation(s) in RCA: 73] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- A W Vorbrodt
- New York State Office of Mental Retardation and Developmental Disabilities, Department of Pathological Neurobiology, Staten Island 10314
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