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Mitochondrial function and brain Metabolic Score (BMS) in ischemic Stroke: Evaluation of "neuroprotectants" safety and efficacy. Mitochondrion 2019; 50:170-194. [PMID: 31790815 DOI: 10.1016/j.mito.2019.11.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Revised: 11/04/2019] [Accepted: 11/21/2019] [Indexed: 02/02/2023]
Abstract
The initial and significant event developed in ischemic stroke is the sudden decrease in blood flow and oxygen supply to brain tissue, leading to dysfunction of the mitochondria. Many attempts were and are being made to develop new drugs and treatments that will save the ischemic brain, but the efficacy is not optimal and in many patients, irreversible damage to the brain will persist. We review a unique approach to evaluate mitochondrial function and microcirculatory hemodynamic in real time in vivo. Three out of four monitored physiological parameters are integrated into a new Brain Metabolic Score (BMS) calculated in real time and is correlated to Brain Oxygen Balance. The technology was adapted to various experimental as well as clinical situations for monitoring the brain in real time. The developed protocols could be used in testing the efficacy and safety of new drugs in experimental animals. Few models of brain monitoring during partial or complete ischemia were developed and used in naive animals or under brain activation protocols. It was found that mitochondrial function/dysfunction is the major and dominant parameter affecting the calculated Brain Metabolic Score. Using our monitoring system and protocols will provide direct information regarding the ability of the tested brain to provide enough oxygen consumed by the mitochondria in the "resting" or in the "activated" brain in vivo and in real-time. Preliminary studies, indicated that testing the efficacy and safety of new neuroprotectant drugs provided significant results to the R&D studies of ischemic stroke related to mitochondrial function.
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Mayevsky A, Barbiro-Michaely E. Shedding light on mitochondrial function by real time monitoring of NADH fluorescence: I. Basic methodology and animal studies. J Clin Monit Comput 2012. [PMID: 23203204 DOI: 10.1007/s10877-012-9414-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Normal mitochondrial function in the process of metabolic energy production is a key factor in maintaining cellular activities. Many pathological conditions in animals, as well as in patients, are directly or indirectly related to dysfunction of the mitochondria. Monitoring the mitochondrial activity by measuring the autofluorescence of NADH has been the most practical approach since the 1950s. This review presents the principles and technological aspects, as well as typical results, accumulated in our laboratory since the early 1970s. We were able to apply the fiber-optic-based NADH fluorometry to many organs monitored in vivo under various pathophysiological conditions in animals. These studies were the basis for the development of clinical monitoring devices as presented in accompanying article. The encouraging experimental results in animals stimulated us to apply the same technology in patients after technological adaptations as described in the accompanying article. Our medical device was approved for clinical use by the FDA.
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Affiliation(s)
- Avraham Mayevsky
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, 52900, Ramat Gan, Israel.
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Mayevsky A, Rogatsky GG. Mitochondrial function in vivo evaluated by NADH fluorescence: from animal models to human studies. Am J Physiol Cell Physiol 2006; 292:C615-40. [PMID: 16943239 DOI: 10.1152/ajpcell.00249.2006] [Citation(s) in RCA: 263] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Normal mitochondrial function is a critical factor in maintaining cellular homeostasis in various organs of the body. Due to the involvement of mitochondrial dysfunction in many pathological states, the real-time in vivo monitoring of the mitochondrial metabolic state is crucially important. This type of monitoring in animal models as well as in patients provides real-time data that can help interpret experimental results or optimize patient treatment. The goals of the present review are the following: 1) to provide an historical overview of NADH fluorescence monitoring and its physiological significance; 2) to present the solid scientific ground underlying NADH fluorescence measurements based on published materials; 3) to provide the reader with basic information on the methodologies used in the past and the current state of the art fluorometers; and 4) to clarify the various factors affecting monitored signals, including artifacts. The large numbers of publications by different groups testify to the valuable information gathered in various experimental conditions. The monitoring of NADH levels in the tissue provides the most important information on the metabolic state of the mitochondria in terms of energy production and intracellular oxygen levels. Although NADH signals are not calibrated in absolute units, their trend monitoring is important for the interpretation of physiological or pathological situations. To understand tissue function better, the multiparametric approach has been developed where NADH serves as the key parameter. The development of new light sources in UV and visible spectra has led to the development of small compact units applicable in clinical conditions for better diagnosis of patients.
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Affiliation(s)
- Avraham Mayevsky
- The Mina & Everard Goodman Faculty of Life Sciences and The Leslie and Susan Gonda Multidisciplinary Brain Research Center, Bar-Ilan Univ., Ramat-Gan 52900, Israel.
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Vatov L, Kizner Z, Ruppin E, Meilin S, Manor T, Mayevsky A. Modeling brain energy metabolism and function: a multiparametric monitoring approach. Bull Math Biol 2006; 68:275-91. [PMID: 16794931 DOI: 10.1007/s11538-005-9008-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2004] [Accepted: 04/07/2005] [Indexed: 11/30/2022]
Abstract
Mathematical modeling of brain function is an important tool needed for a better understanding of experimental results and clinical situations. In the present study, we are constructing and testing a mathematical model capable of simulating changes in brain energy metabolism that develop in real time under various pathophysiological conditions. The model incorporates the following parameters: cerebral blood flow, partial oxygen pressure, mitochondrial NADH redox state, and extracellular potassium. Accordingly, all the model variables are only time dependent (;point-model' approach). Numerical runs demonstrate the ability of the model to mimic pathological conditions, such as complete and partial ischemia, cortical spreading depression under normoxic and partial ischemic conditions. They also show that, when properly tuned, a model of this type permits the monitoring of only one or two crucial variables and the computation of the remaining variables in real time during clinical or experimental procedures.
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Affiliation(s)
- Larisa Vatov
- Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, 52900, Israel
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Mayevsky A, Manor T, Pevzner E, Deutsch A, Etziony R, Dekel N, Jaronkin A. Tissue spectroscope: a novel in vivo approach to real time monitoring of tissue vitality. JOURNAL OF BIOMEDICAL OPTICS 2004; 9:1028-45. [PMID: 15447025 DOI: 10.1117/1.1780543] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Optical monitoring of various tissue physiological and biochemical parameters in real-time represents a significant new approach and a tool for better clinical diagnosis. The Tissue Spectroscope (TiSpec), developed and applied in experimental and clinical situations, is the first medical device that enables the real-time monitoring of three parameters representing the vitality of the tissue. Tissue vitality, which is correlated to the oxygen balance in the tissue, is defined as the ratio between O(2) supply and O(2) demand. The TiSpec enables the monitoring of microcirculatory blood flow (O(2) supply), mitochondrial NADH redox state (O(2) balance), and tissue reflectance, which correlates to blood volume. We describe in detail the theoretical basis for the monitoring of the three parameters and the technological aspects of the TiSpec. The comparison between the TiSpec and the existing single parameter monitoring instruments shows a statistically significant correlation as evaluated in vitro as well as in various in vivo animal models. The results presented originated in a pilot study performed in vivo in experimental animals. Further research is needed to apply this technology clinically. The clinical applications of the TiSpec include two situations where the knowledge of tissue vitality can improve clinical practice. The major application is the monitoring of "nonvital" organs of the body [i.e., the skin, gastrointestinal (G-I) tract, urethra] in emergency situations, such as in the operating rooms and intensive care units. Also, the monitoring of specific (vital) organs, such as the brain or the heart, during surgical procedure is of practical importance.
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Affiliation(s)
- Avraham Mayevsky
- Bar-Ilan University, Faculty of Life Sciences, Ramat Gan 52900, Israel.
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Simonovich M, Barbiro-Michaely E, Salame K, Mayevsky A. A new approach to monitor spinal cord vitality in real time. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2004; 540:125-32. [PMID: 15174611 DOI: 10.1007/978-1-4757-6125-2_18] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
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Shashoua VE, Adams DS, Boyer-Boiteau A, Cornell-Bell A, Li F, Fisher M. Neuroprotective effects of a new synthetic peptide, CMX-9236, in in vitro and in vivo models of cerebral ischemia. Brain Res 2003; 963:214-23. [PMID: 12560127 DOI: 10.1016/s0006-8993(02)04058-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
NGF (nerve growth factor) and BDNF (brain-derived neurotrophic factor) are protein molecules (MW 26 and 13.6 kDa, respectively) that are neuroprotective in the middle cerebral artery occlusion (MCAO) rat stroke model. Their mechanism of action involves the activation of transcription factor AP-1 that turns on neuronal growth genes. In our ongoing studies we are designing short peptides that mimic some of the properties of full-length neurotrophic factors. We have synthesized a neuroprotective 14-amino acid peptide (CMX-9236) with an N-terminal docosahexaenoic acid (DHA). DHA enhances entry through the blood-brain barrier. Using primary rat brain cortical cultures and a fluorescent assay we found that CMX-9236 can counteract the excitotoxic effects of glutamate or kainate, reversing the intracellular accumulation of Ca(2+) to normal levels. Administration (i.v.) of CMX-9236 post initiation of ischemia reduced the lesion volumes from 178+/-50 to 117+/-55 mm(3) in the temporary rat MCAO model (90 min), and from 216+/-58 to 127+/-57 mm(3) in the permanent (24 h) model for stroke, corresponding to 34+/-28% (P=0.01) and 41+/-19% (P=0.038) reductions of the infarct volumes. Neurological behavior scores showed 57 and 47% improvements for treated temporary and permanent models, respectively. Dose-response studies indicated a 60-fold activation of AP-1 transcription factor in cells treated with 100 ng/ml of the peptide. These studies illustrate that a small peptide can function as a neuroprotective agent and an activator of a beneficial signal transduction pathway.
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Affiliation(s)
- Victor E Shashoua
- CereMedix, Inc., 317 Egan Research Center, Northeastern University, 120 Forsyth Street, Boston, MA 02115, USA.
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Mayevsky A, Barbiro-Michaely E, Ligeti L, MacLaughlin AC. Effects of euthanasia on brain physiological activities monitored in real-time. Neurol Res 2002; 24:647-51. [PMID: 12392199 DOI: 10.1179/016164102101200690] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
Animal experimentation is terminated by the euthanasia procedure in order to avoid pain and minimize suffering. Very little is known about the real time physiological changes taking place in the brain of animals during the euthanasia. Since there is no way to evaluate the suffering of animals under euthanasia, it is assumed that objective physiological changes taking place could serve as a good way to compare various types of euthanasia procedures. In the present study we compared the effect of euthanasia induced by i. v. injection of concentrated KCL to that of Taxan T-61 (a standard mixture used by veterinarians). The responses of the cat brain were evaluated by monitoring the hemodynamic (CBF), metabolic (NADH redox state), electrical (EcoG) and extracellular ion levels, as an indicator to the ionic homeostasis.
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Affiliation(s)
- Avraham Mayevsky
- Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel.
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Tian GF, Baker AJ. Protective effect of high glucose against ischemia-induced synaptic transmission damage in rat hippocampal slices. J Neurophysiol 2002; 88:236-48. [PMID: 12091549 DOI: 10.1152/jn.00572.2001] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Cerebral ischemic damage is an important cause of morbidity and mortality. However, there is conflicting evidence regarding the effect of the extracellular glucose concentration in focal and global ischemic injury. This study was designed to investigate this effect in ischemia-induced synaptic transmission damage in rat hippocampal slices. Slices were superfused with artificial cerebrospinal fluid (ACSF) containing various concentrations of glucose before and after ischemia. The evoked somatic postsynaptic population spike (PS) and dendritic field excitatory postsynaptic potential (fEPSP) were extracellularly recorded in the CA1 stratum pyramidal cell layer and s. radiatum after stimulation of the Schaeffer collaterals, respectively. The glucose concentration in ACSF before and after ischemia determined the duration of ischemia tolerated by synaptic transmission as demonstrated by complete recovery of the somatic PS and dendritic fEPSP. Specifically, the somatic PS and dendritic fEPSP completely recovered following 3, 4, and 5 min of ischemia only when slices were superfused with ACSF containing 4, 10, and 20 mM glucose before and after ischemia, respectively. The latencies of the somatic and dendritic ischemic depolarization (ID) occurrence in the CA1 s. pyramidal cell layer and s. radiatum were significantly longer with 10 than 4 mM glucose in ACSF before ischemia and significantly longer with 20 than 10 mM glucose in ACSF before ischemia. Regardless of the glucose concentration in ACSF before and after ischemia, the somatic PS and dendritic fEPSP only partially recovered when ischemia was terminated at the occurrence of ID. These results indicate that high glucose in ACSF during the period before and after ischemia significantly protects CA1 synaptic transmission against in vitro ischemia-induced damage through postponing the occurrence of ID.
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Affiliation(s)
- Guo-Feng Tian
- Traumatic Brain Injury Laboratory, Cara Phelan Centre for Trauma Research and Department of Anaesthesia, St. Michael's Hospital, University of Toronto, Toronto, Ontario M5B 1W8 Canada.
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Mayevsky A, Rogatsky GG, Sonn J. New multiparametric monitoring approach for real-time evaluation of drug tissue interaction in vivo. Drug Dev Res 2000. [DOI: 10.1002/1098-2299(200007/08)50:3/4<457::aid-ddr29>3.0.co;2-p] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Zarchin N, Guggenheimer-Furman E, Meilin S, Ornstein E, Mayevsky A. Thiopental induced cerebral protection during ischemia in gerbils. Brain Res 1998; 780:230-6. [PMID: 9507147 DOI: 10.1016/s0006-8993(97)01188-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Temporary interruption or reduction of cerebral blood flow during cerebrovascular surgery may rapidly result in ischemia or cerebral infarction. Thiopental has been shown to have cerebroprotective effects. However, the cerebroprotective dose of thiopental causes burst suppression of the EEG, thus this parameter cannot be used continuously for the detection of metabolic changes in the brain during thiopental anaesthesia. This study was performed in order to examine whether the multiparametric assembly (MPA), which measures energy metabolism CBF and mitochondrial (NADH) as well as extracellular ion concentrations (K+), can shed light on the mechanism of the cerebroprotective effects of thiopental. The MPA was placed on the brain of Mongolian gerbils and burst suppression of the ECoG was induced by thiopental. Cerebral ischemia was induced by occlusion of carotid arteries after burst suppression. Burst suppression of the ECoG was accompanied by a significant decrease in cerebral blood flow. In animals that received thiopental prior to ischemia, NADH increased to a lesser degree and extracellular potassium ion concentration increased to a lesser degree than in the control animals, indicating that thiopental affords protection of the brain under ischemic conditions due to improved energy metabolism. This study also demonstrates that the MPA can monitor changes occurring in the cerebral cortex even after the ECoG can no longer be used. Those findings have a significant value in the development of a new clinical monitoring device.
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Affiliation(s)
- N Zarchin
- Department of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel
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12
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Ligeti L, Mayevsky A, Ruttner Z, Kovach AG, McLaughlin AC. Can the Indo-1 fluorescence approach measure brain intracellular calcium in vivo? A multiparametric study of cerebrocortical anoxia and ischemia. Cell Calcium 1997; 21:115-24. [PMID: 9132294 DOI: 10.1016/s0143-4160(97)90035-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Indo-1 fluorescence was used to monitor intracellular calcium levels in the cat brain in vivo, using the approach proposed by Uematsu et al. [Uematsu D., Greenberg J. H., Reivich M., Karp A. In vivo measurement of cytosolic free calcium during cerebral ischemia and reperfusion. Ann Neurol 1988; 24: 420-428]. In addition, extracellular calcium and potassium levels, NADH redox state, electrocorticogram (ECoG), DC potential and relative cerebral blood flow were monitored simultaneously. Changes in the Indo-1 fluorescence ratio F400/F506 were monitored during anoxia, reversible ischemia and irreversible ischemia. Although these perturbations resulted in the expected changes in extracellular calcium and potassium levels, NADH redox state, ECoG and other physiological parameters, they did not result in significant increases in the F400/F506 ratio. The apparent insensitivity of the in vivo Indo-1 approach is due to the difficulty in obtaining accurate fluorescence signals from Indo-1 in the brain. Two reasons for this difficulty appear to be problems in loading Indo-1 into the brain, and problems in correcting Indo-1 fluorescence signals for changes in NADH fluorescence and changes in absorption of intrinsic chromophores. Under the conditions of our in vivo cat experiments, Indo-1 fluorescence is not a viable approach for measuring changes in cerebral intracellular calcium levels.
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Affiliation(s)
- L Ligeti
- National Institute on Alcohol Abuse and Alcoholism, NIH, Rockville, Maryland 20892, USA
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13
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Osbakken M, Mayevsky A. Multiparameter monitoring and analysis of in vivo ischemic and hypoxic heart. J Basic Clin Physiol Pharmacol 1996; 7:97-113. [PMID: 8876429 DOI: 10.1515/jbcpp.1996.7.2.97] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
We describe a unique in vivo technique which addresses the multifactorial function of the heart, i.e., simultaneous measurement of myocardial ion transport (two mini-electrode systems to measure K+e and Ca2+e), energy metabolism (NADH fluorescence to measure NADH redox state), and coronary flow (laser-Doppler perfusion) using a multiprobe assembly (MPA) which contains transducers for all measurements. The MPA (which is 6 mm in diameter) was applied to the external surface of the heart in an open chest dog model. To test MPA function, myocardial ischemia was produced by application of a balloon occluder to the left anterior descending coronary (LAD) artery, and hypoxia was produced by changing the inspired O2-N2 ratio until the PaO2 was 20-30 torr. The MPA simultaneously monitored changes in ion flux, heart metabolism, and tissue perfusion during pathophysiological intervention.
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Affiliation(s)
- M Osbakken
- Department of Biochemistry/Biophysics, University of Pennsylvania, Philadelphia, USA
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14
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Watson GB, Lanthorn TH. Phenytoin delays ischemic depolarization, but cannot block its long-term consequences, in the rat hippocampal slice. Neuropharmacology 1995; 34:553-8. [PMID: 7566490 DOI: 10.1016/0028-3908(95)00005-q] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The anticonvulsant phenytoin has been reported to block anoxia-induced losses of synaptic activity in the rat hippocampal slice and experimental ischemia-induced losses of synaptic activity in the guinea pig hippocampal slice. We examined phenytoin in our rat hippocampal slice model of experimental ischemia (anoxia +2 mM D-glucose). In this model, ischemic depolarization (ID) occurs 4-5 min after the introduction of anoxic medium, and oxygen and D-glucose are restored 1 min after the onset of ID. In control slices, synaptic recovery is never observed following ID in 2 mM D-glucose. Phenytoin (30,100 and 300 microM), perfused for 20 min prior to, and for 10 min following anoxia, did not allow for synaptic recovery following ID. At the higher concentrations, however, it did increase the latency to ID. In addition, the presynaptic volley (PV), which normally disappears at the time of ID, was lost substantially earlier in the presence of phenytoin. These findings suggest that the anti-ischemic effects of phenytoin reported by others are due to delay of ID. This may suggest that phenytoin will be effective in preventing global ischemia-induced damage only when the ischemic insult is of short duration.
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Affiliation(s)
- G B Watson
- Neurological Diseases Research, Searle Research and Development, Skokie, IL 60077, USA
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Stittsworth JD, Lanthorn TH. Comparison of neuronal responses to experimental ischemia in gerbil and rat hippocampal slices. Brain Res 1994; 649:353-6. [PMID: 7953652 DOI: 10.1016/0006-8993(94)91087-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The present study utilized in vitro gerbil and rat hippocampal slices to compare responses to experimental ischemia without species differences in the cerebrovasculature as a variable. Ischemic depolarization occurred faster in the gerbil (2.53 +/- 0.05 min) than in the rat (4.59 +/- 1.1 min). These results indicate that the gerbil's greater propensity to neuronal damage following short ischemic periods may be due to greater sensitivity of the gerbil brain itself.
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Osbakken MD. Metabolic regulation of in vivo myocardial contractile function: multiparameter analysis. Mol Cell Biochem 1994; 133-134:13-37. [PMID: 7808451 DOI: 10.1007/bf01267945] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
To gain insight into the mechanisms of myocardial regulation as it relates to the interaction of mechanical and metabolic function and perfusion, intact animal models were instrumented for routine physiological measurements of mechanical function and for measurements of metabolism (31P NMR, NADH fluorescence (redox state)) and perfusion (2H NMR and Laser doppler techniques). These techniques were applied to canine and cat models of volume and/or pressure loading, hypoxia, ischemia and cardiomyopathic states. Data generated using these techniques indicate that myocardial bioenergetic function is quite stable under most loading conditions as long as the heart is not ischemic. In addition, these data indicate that there is no universal regulator and that different biochemical regulators appear to mediate stable function under different physiological and pathophysiological conditions: for example; during hypoxia, NADH redox state appears to play a regulatory role; and in pressure loading, ADP, phosphorylation potential and free energy of ATP hydrolysis as well as NADH redox state appear to be regulatory.
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Affiliation(s)
- M D Osbakken
- Department of Medicine, University of Pennsylvania, Philadelphia 19104
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17
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Stittsworth JD, Lanthorn TH. Resistance to epileptic, but not anoxic, depolarization in the gerbil hippocampal slice preparation. Neurosci Lett 1994; 168:8-10. [PMID: 8028797 DOI: 10.1016/0304-3940(94)90403-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The Mongolian gerbil displays spontaneous seizures and is used as a model for global ischemia. This study investigated the electrophysiological events associated with 0-Mg(2+)-induced seizures in gerbil hippocampal slices. In the rat hippocampal slice, 0-Mg2+ medium leads to rapid extracellular epileptic depolarization (ED) accompanied by long-term synaptic failure. Both evoked and spontaneous epileptiform activity was observed in the gerbil hippocampal slice after the introduction of the 0-Mg2+ aCSF. However, unlike the rat, ED was rarely observed in the gerbil hippocampal slice (2/17). When ED occurred, synaptic responses recovered (75%) within 20 min. This resistance to epileptic depolarization did not generalize to experimental ischemia-induced depolarization. Anoxia in 2 mM D-glucose produced anoxic depolarization in all gerbil hippocampal slices tested (6/6).
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Ishimaru H, Ikarashi Y, Takahashi A, Maruyama Y. Acute neurochemical changes in mouse brain following cerebral ischemia. Eur Neuropsychopharmacol 1993; 3:485-91. [PMID: 8111221 DOI: 10.1016/0924-977x(93)90273-o] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Acute changes in neurochemical levels induced by ischemia were studied in the mouse brain. Contents of neurochemicals in the frontal, parietal and occipital cortices and hippocampus were determined immediately after 15 min of ischemia (0), and then at 15, 30, 90 and 180 min after recirculation following ischemia. These data were compared with those for sham-operated control mice. Choline (Ch) contents in ischemic animals increased by 530-630% from control levels immediately after ischemia, and returned to control levels by 90 min. Decreases in levels of norepinephrine (NE) and serotonin (5-HT) were observed during 30 min after recirculation. There were no significant changes in levels of acetylcholine (ACh) or dopamine (DA), throughout recirculation. On the other hand, DA and 5-HT metabolites (3,4-dihydroxyphenylacetic acid and 5-hydroxyindoleacetic acid) significantly increased. Thus, comprehensively investigating the various neurotransmitters will provide meaningful information regarding the disturbance of central nervous system induced by cerebrovascular disease.
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Affiliation(s)
- H Ishimaru
- Department of Neuropsychopharmacology (Tsumara), Gunma University, School of Medicine, Japan
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Mayevsky A, Frank K, Muck M, Nioka S, Kessler M, Chance B. Multiparametric evaluation of brain functions in the Mongolian gerbil in vivo. J Basic Clin Physiol Pharmacol 1992; 3:323-42. [PMID: 1339223 DOI: 10.1515/jbcpp.1992.3.4.323] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
We have developed the multiprobe assembly (MPA) by which metabolic, ionic and electrical activities can be monitored from the surface of the brain. In the present study we included optical fibers for the monitoring of intracapillary hemoglobin oxygenation by use of the Erlangen Microlight Guide Spectrophotometer (EMPHO-I) from the surface of the gerbil brain. The newly developed MPA provides simultaneous information about oxygen delivery (oxydeoxy Hb), tissue pO2 level, as well as the intracellular oxygen balance (intramitochondrial redox state). The ionic homeostasis was evaluated by monitoring extracellular K+ and Ca2+ activities reflecting the permeability changes of cation channels as well as the activities of Na+,K(+)-ATPase and other ion linked transport processes. The electrical activities were monitored by a bipolar electrocortical surface probe and DC steady potential. The subjects of the present study were Mongolian gerbils (Meriones unguiculatus) anesthetized and operated according to our routine techniques. After 30 min of recovery from the operation each gerbil was exposed to a short anoxia, graded hypoxia, ischemia as well as spreading depression. The results can be summarized as follows: 1. A clear correlation was recorded between the changes in oxydeoxy Hb spectra, tissue pO2 level and oxidation-reduction state of intramitochondrial NADH under oxygen deficiency situations (hypoxia, ischemia). 2. Blood volume changes under various perturbations monitored by various probes (366 reflectance and EMPHO-I) correlated very well with each other. 3. The degree of inhibition of Na+,K(+)-ATPase induced by oxygen deficiency could be interpreted by changes in extracellular levels of K+ measured by the surface mini-electrode. 4. Brain stimulation induced by spreading depression mechanism led to transient changes in ionic homeostasis and increase in energy requirements. The major HbO2 response was an increase in oxygenation due to the large CBF increase as monitored by the laser Doppler flowmeter. 5. Changes in oxy-deoxy Hb under fast scanning of 500-600 nm during 2-3 seconds of bilateral carotid arterial occlusion provided an indirect index for tissue O2 consumption.
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Affiliation(s)
- A Mayevsky
- Department of Life Sciences, Bar-Ilan University, Ramat Gan, Israel
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Mayevsky A. Cerebral blood flow and brain mitochondrial redox state responses to various perturbations in gerbils. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1992; 317:707-16. [PMID: 1288193 DOI: 10.1007/978-1-4615-3428-0_85] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- A Mayevsky
- Department of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel
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