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1.
J Neurol Sci ; 279(1-2): 118-20, 2009 Apr 15.
Article in English | MEDLINE | ID: mdl-19185318

ABSTRACT

We report on a 27-year-old man with Fabry disease who had widespread white-matter lesions (WMLs) despite the absence of renal or cardiac manifestations. Genomic analysis revealed a novel mutation: a GAT deletion at nucleotide position 234-236 in exon 5 of the coding region. After 12 months of enzyme replacement therapy (ERT), most of the WMLs had disappeared. Cell counts and protein levels in the cerebrospinal fluid also decreased. These findings suggest that ERT may play a role in the recovery of WMLs.


Subject(s)
Brain/drug effects , Fabry Disease/drug therapy , Nerve Fibers, Myelinated/drug effects , alpha-Galactosidase/therapeutic use , Adult , Brain/pathology , Fabry Disease/genetics , Fabry Disease/pathology , Humans , Magnetic Resonance Imaging , Male , Nerve Fibers, Myelinated/pathology , Sequence Deletion , Treatment Outcome , alpha-Galactosidase/genetics
2.
Heart ; 94(3): 316-21, 2008 Mar.
Article in English | MEDLINE | ID: mdl-17591648

ABSTRACT

BACKGROUND: Arachidonic acid (ARA) and docosahexaenoic acid (DHA) are important components of phospholipids and cell membranes. There has, however, been no clinical report on the direct effects of ARA and DHA on coronary circulation. OBJECTIVE: To evaluate the effects of ARA and DHA on coronary circulation using the measurement of coronary flow velocity reserve (CFVR) by transthoracic Doppler echocardiography (TTDE). METHODS: A double-blind, placebo-matched study of 28 Japanese elderly individuals (19 men, mean age 65 years) conducted to compare the effects of polyunsaturated fatty acids (PUFA; ARA 240 mg/day, DHA 240 mg/day) and placebo on CFVR. Coronary flow velocity (CFV) of the left anterior descending coronary artery was measured at rest and during hyperaemia by TTDE to determine CFVR. RESULTS: There were no significant differences in CFV at rest or during hyperaemia in CFVR at baseline in the two groups (PUFA versus placebo 17 (7 SD) versus 16 (6), 62 (20) versus 59 (12), and 3.85 (1.04) versus 3.98 (0.83) cm/s, respectively). After three months' supplementation, CFV during hyperaemia was significantly higher in the PUFA than in the placebo group (73 (19) versus 64 (12) cm/s, p<0.01) although no significant difference was found between the two groups in CFV at rest (17 (7) versus 16 (4) cm/s). CFVR thus significantly increased after PUFA consumption (3.85 (1.04) versus 4.46 (0.95), p = 0.0023). CONCLUSION: Three months' supplementation of PUFA increased CFVR in Japanese elderly individuals, which suggests beneficial effects of PUFA on the coronary microcirculation.


Subject(s)
Arachidonic Acid/pharmacology , Blood Flow Velocity/drug effects , Coronary Circulation/drug effects , Coronary Vessels/drug effects , Docosahexaenoic Acids/pharmacology , Aged , Blood Flow Velocity/physiology , Coronary Circulation/physiology , Coronary Vessels/diagnostic imaging , Coronary Vessels/physiology , Echocardiography/methods , Echocardiography, Doppler, Color/methods , Epidemiologic Methods , Erythrocyte Membrane/diagnostic imaging , Erythrocyte Membrane/drug effects , Erythrocyte Membrane/physiology , Female , Humans , Male
4.
Neurol Clin Neurophysiol ; 2004: 76, 2004 Nov 30.
Article in English | MEDLINE | ID: mdl-16012622

ABSTRACT

Recent development of auditory-evoked magnetoencephalography (A-MEG) made it possible to measure interhemispheric neural conduction time (INCT) of auditory impulses. We estimated INCT with A-MEG and cognitive function with mini-mental state examination (MMSE) in 85 elderly patients with chronic dizziness (CD) and found that INCT was negatively correlated with MMSE scores (p<0.001). In 11 of 85 patients whose MMSE scores were within the normal range, A-MEG and MMSE were repeated for the subsequent 4 years to find longitudinal changes in INCT and cognitive function. The 11 patients were divided into two groups according to the baseline INCT values, such as Group A with normal INCT (n=7) and Group B with abnormally prolonged INCT (n=4). In Group A, INCT and MMSE scores remained within the normal range throughout the 4-year period. In Group B, INCT showed the tendency towards progressive prolongation during the follow-up period, and MMSE scores decreased to abnormally low levels at the third or fourth follow-up year in all the patients. The present results suggest that rapid neural interaction of both cerebral hemispheres is needed to maintain normal cognitive function. Abnormal INCT prolongation in elderly subjects suggests subclinical cortical network dysfunction and may predict the future development of cognitive deterioration.


Subject(s)
Cognition Disorders/diagnosis , Cognition Disorders/physiopathology , Evoked Potentials, Auditory/physiology , Magnetoencephalography/methods , Acoustic Stimulation/methods , Adult , Aged , Follow-Up Studies , Humans , Middle Aged , Neural Conduction/physiology , Neuropsychological Tests , Predictive Value of Tests
6.
Med Biol Eng Comput ; 40(3): 327-31, 2002 May.
Article in English | MEDLINE | ID: mdl-12195980

ABSTRACT

The aim of the study was to develop a method for investigating how interictal epileptic discharges in temporal epilepsy patients are activated spatially. The activity was measured using magneto-encephalography (MEG). The MEG data were used to produce a current-arrow map that reflected the topographic distribution of the electrical current for each peak epileptic waveform. A large current distribution was obtained that appeared to be contained in the limbic structure, in each temporal lobe. The large current orientation indicated two opposite directions. Furthermore, the decrease in the maximum strength of the current-arrow, depending on the medication (e.g. the decrease from 11 to 6 pT m-1 in the left temporal lobe (contralateral stimuli)), suggested that the discharge distributions could be used to verify the efficacy of medication. Thus the topographical visualisation method could be a new strategy for diagnosis in temporal epilepsy patients.


Subject(s)
Epilepsy, Temporal Lobe/diagnosis , Magnetoencephalography/methods , Aged , Aged, 80 and over , Female , Humans , Kindling, Neurologic , Male , Middle Aged , Signal Processing, Computer-Assisted
7.
Proc Natl Acad Sci U S A ; 98(17): 10017-22, 2001 Aug 14.
Article in English | MEDLINE | ID: mdl-11481450

ABSTRACT

Human craniofacial data were used to assess the similarities and differences between recent and prehistoric Old World samples, and between these samples and a similar representation of samples from the New World. The data were analyzed by the neighbor-joining clustering procedure, assisted by bootstrapping and by canonical discriminant analysis score plots. The first entrants to the Western Hemisphere of maybe 15,000 years ago gave rise to the continuing native inhabitants south of the U.S.-Canadian border. These show no close association with any known mainland Asian population. Instead they show ties to the Ainu of Hokkaido and their Jomon predecessors in prehistoric Japan and to the Polynesians of remote Oceania. All of these also have ties to the Pleistocene and recent inhabitants of Europe and may represent an extension from a Late Pleistocene continuum of people across the northern fringe of the Old World. With roots in both the northwest and the northeast, these people can be described as Eurasian. The route of entry to the New World was at the northwestern edge. In contrast, the Inuit (Eskimo), the Aleut, and the Na-Dene speakers who had penetrated as far as the American Southwest within the last 1,000 years show more similarities to the mainland populations of East Asia. Although both the earlier and later arrivals in the New World show a mixture of traits characteristic of the northern edge of Old World occupation and the Chinese core of mainland Asia, the proportion of the latter is greater for the more recent entrants.


Subject(s)
Asian People/history , Cephalometry , Emigration and Immigration/history , Ethnicity/history , Facial Bones/anatomy & histology , Americas , Animals , Anthropology, Physical , Asia , Australia , Cluster Analysis , Europe , Fossils , History, Ancient , History, Medieval , Hominidae/anatomy & histology , Humans , Phylogeny , Polynesia
8.
J Psychiatr Res ; 34(3): 227-38, 2000.
Article in English | MEDLINE | ID: mdl-10867118

ABSTRACT

This study examined changes in directed attention and short-term memory in depression using a newly constructed battery of computerized measures. A repeated measures design was used with two sample groups; 25 individuals meeting DSM-IV criteria for Major Depression and a group-matched comparison sample of 27. Both groups were tested at three points in time over a 10-week period. Test-retest reliability of the measures was examined. Profile analysis demonstrated that there were differences between the depressed and comparison groups in both directed attention and short-term memory. Recommendations for specific improvements in the testing battery are discussed. The ability to detect changes in directed attention and short-term memory may have clinical utility in early detection of impending onset of depression or subtle residual symptoms of an acute episode that may impair functioning or signal a relapse.


Subject(s)
Attention , Depressive Disorder, Major/diagnosis , Depressive Disorder, Major/psychology , Memory, Short-Term , Adult , Case-Control Studies , Depression/diagnosis , Depression/psychology , Female , Humans , Male , Neuropsychological Tests , Prospective Studies , Psychiatric Status Rating Scales , Reproducibility of Results , Time Factors
9.
Rinsho Shinkeigaku ; 39(4): 485-8, 1999 Apr.
Article in Japanese | MEDLINE | ID: mdl-10391981

ABSTRACT

A 32-year-old man with hemiconvulsions, hemiplegia, epilepsy (HHE) syndrome is described. He was well developed with a normal pregnancy and delivery, but at age 10 months, he had status epilepticus during a febrile illness. Thereafter, he was noted to have left hemiparesis and mental retardation with recurrent hemiconvulsions. Magnetic resonance (MR) images showed atrophy and degeneration of the right cerebral cortex and white matter, homolateral thalamus, caudate nucleus, and hippocampus, with hyperintensities in both T2-weighted (TR/2200, TE/90) and proton (TR/2200, TE/30) images. There were also slight bilateral cerebellar atrophies. Quantitative single photon emission computed tomographic (SPECT) images using technetium-99m-ethyl cysteinate dimer (99mTc-ECD) revealed markedly reduced cerebral blood flow (CBF) in the right cerebral hemisphere, homolateral thalamus, caudate nucleus and bilateral cerebellum. Bilateral putamen and the medial occipital lobe showed normal findings on MR images and normal regional CBF in SPECT images. We suppose these selective neuronal injures in this case of HHE syndrome will be mainly due to histotoxic factors in epileptic brain damage.


Subject(s)
Epilepsy/diagnosis , Hemiplegia/diagnosis , Seizures/diagnosis , Adult , Atrophy , Brain/pathology , Cerebrovascular Circulation , Humans , Magnetic Resonance Imaging , Male , Nerve Degeneration , Syndrome , Tomography, Emission-Computed, Single-Photon
10.
Jpn Circ J ; 62(1): 72-6, 1998 Jan.
Article in English | MEDLINE | ID: mdl-9559422

ABSTRACT

We report here on a 73-year-old woman who ingested 3.6 g (40 mg x 90 tablets) of verapamil in a suicide attempt. On arrival, the patient was awake and well oriented. Two and a half hours after ingestion, she lost consciousness, as her heart rate and blood pressure began to decrease. Cardiac monitoring showed atrioventricular dissociation. Although she suffered from extreme hypotension, an echocardiogram revealed that the wall motion of the heart was almost normal, and cardiac output measured with a Swan-Ganz catheter was well preserved. The plasma verapamil concentration in this patient was 1499 ng/ml 4 h after ingestion. Hyperglycemia and hypokalemia, laboratory data revealed, continued for 18 h after admission. The patient was successfully resuscitated with intravenous saline, dopamine, and norepinephrine. Besides reporting on this case, we also report on a treatment for severe verapamil overdose.


Subject(s)
Calcium Channel Blockers/poisoning , Verapamil/poisoning , Aged , Drug Overdose/therapy , Female , Humans , Japan/epidemiology , Suicide, Attempted
11.
Rinsho Shinkeigaku ; 36(10): 1166-71, 1996 Oct.
Article in Japanese | MEDLINE | ID: mdl-8997142

ABSTRACT

We described a 60-year-old man with 5-year history of insulin dependent diabetes mellitus who developed continuous rigidity of truncal muscle and painless, rhythmic muscular spasm of trunk and proximal lower and upper extremities. The rigidity continued even in sleep. The painless muscle spasm was often precipitated by volitional movement and emotional stimuli. Intravenous administration of diazepam strongly attenuated the muscle spasm as well as truncal rigidity. Surface electromyography showed the continuous contraction of abdominal and paraspinal muscles. The rhythmic, clonic spasm of shoulder, triceps brachii, intercostal, abdominal, paraspinal and quadriceps femoris muscle induced by voluntary neck flexion was not compatible with typical stiff-man syndrome. Antibody against glutamic acid decarboxylase (GAD) was detected in the serum and cerebrospinal fluid of this patient. His condition was getting well with oral intake of sodium valproate. While painless, rhythmic spasm and persistent rigidity during sleep ruled out the patient from typical stiff-man syndrome, he was supposed to have the same pathophysiological mechanism as the anti-GAD autoantibody positive stiff-man syndrome.


Subject(s)
Autoantibodies/blood , Glutamate Decarboxylase/immunology , Muscle Rigidity/complications , Spasm/complications , Analgesia , Diabetes Mellitus, Type 1/complications , Electromyography , Humans , Male , Middle Aged , Muscle Rigidity/immunology , Muscle Rigidity/physiopathology , Spasm/immunology , Spasm/physiopathology
12.
Nihon Kyobu Shikkan Gakkai Zasshi ; 34(4): 459-64, 1996 Apr.
Article in Japanese | MEDLINE | ID: mdl-8691669

ABSTRACT

A 47-year-old man complaining of common cold-like symptoms was admitted to our hospital. Acute myelogenous leukemia was diagnosed and the patient was treated with induction chemotherapy. During granulocytopenia caused by induction chemotherapy, a nodular lesion appeared in the right upper lobe. The nodular lesion changed to a cavitary lesion after the recovery of peripheral white blood cell counts. A transbronchial biopsy specimen obtained from the right B3b showed Aspergillus. Oral itraconozole, flucytosine, and intravenous amphotericin B were given. The cavitary lesion in the right upper lobe regressed after anti-fungal therapy was started. During granulocytopenia caused by consolidation chemotherapy, the nodular lesion enlarged again. Thereafter, as bone marrow recovered, it changed to a cavitary lesion with a lung ball inside. In both episodes, a nodular lesion appeared during granulocytopenia, and changed to a cavitary lesion after bone marrow recovery. In addition, the level of neutrophil elastase reached its maximum at the time of the bone marrow recovery. These findings suggest that white blood cells of the host as well as neutrophil elastase play an important role in cavitation in pulmonary aspergillosis.


Subject(s)
Aspergillosis/complications , Leukemia, Myeloid, Acute/complications , Leukocyte Elastase/physiology , Lung Diseases, Fungal/complications , Lung/pathology , Neutrophils/enzymology , Pancreatic Elastase/physiology , Aspergillosis/enzymology , Humans , Lung Diseases, Fungal/enzymology , Male , Middle Aged
13.
Am J Physiol ; 267(4 Pt 2): H1396-402, 1994 Oct.
Article in English | MEDLINE | ID: mdl-7943384

ABSTRACT

The accumulation of arachidonic acid and lipoxygenase metabolites of arachidonate occurs in ischemic-reperfused myocardium. Although lipoxygenase inhibitors have been shown to attenuate myocardial infarct size after ischemia-reperfusion, the relationship between arachidonate lipoxygenation and myocardial injury remains unclear. To investigate the direct effect of arachidonate lipoxygenation on cardiac myocytes, isolated rat cardiac myocytes loaded with indo 1 were superfused with Tyrode solution containing arachidonic acid mixed with soybean lipoxygenase. Although neither arachidonic acid nor lipoxygenase alone had any effects, arachidonic acid plus lipoxygenase induced an increase in the twitch amplitude associated with an increased intracellular Ca2+ concentration ([Ca2+]i) and irreversible hypercontracture. Nordihydroguaiaretic acid, a lipoxygenase inhibitor, blocked these effects. Linolenic acid, which is also a lipoxygenase substrate, caused the same effects as arachidonic acid in the presence of lipoxygenase, whereas oleic and stearic acid, which do not function as lipoxygenase substrates, did not. Both ascorbic acid and alpha-tocopherol attenuated an increase in [Ca2+]i and the cellular damage, whereas nicardipine and superoxide dismutase had no effects. These results suggest that lipoxygenase metabolites of arachidonic acid cause intracellular Ca2+ overload and cellular damage to cardiomyocytes, probably through augmentation of lipid peroxidation of the cell membranes by free radicals.


Subject(s)
Arachidonic Acid/metabolism , Calcium/metabolism , Heart/physiology , Lipid Peroxidation , Myocardium/metabolism , Myocardium/pathology , Animals , Arachidonic Acid/pharmacology , Cells, Cultured , Electric Stimulation , Fluorescent Dyes , Free Radical Scavengers , Heart/drug effects , Heart Ventricles , Indoles , Lipoxygenase/metabolism , Lipoxygenase/pharmacology , Myocardial Contraction/drug effects , Myocardial Contraction/physiology , Oleic Acid , Oleic Acids/metabolism , Oleic Acids/pharmacology , Rats , Rats, Wistar , Stearic Acids/metabolism , Stearic Acids/pharmacology , alpha-Linolenic Acid/metabolism , alpha-Linolenic Acid/pharmacology
14.
Cardiovasc Res ; 28(7): 1083-8, 1994 Jul.
Article in English | MEDLINE | ID: mdl-7954595

ABSTRACT

OBJECTIVES: The aim was to investigate whether adenosine release after reperfusion contributes to infarct limitation by ischaemic preconditioning. METHODS: Dogs underwent preconditioning with four 5 min cycles of left anterior descending coronary artery (LAD) occlusion and reperfusion, followed by 90 min LAD occlusion and 5 h reperfusion with or without the non-specific adenosine receptor blocker, 8-phenyltheophylline (8-PT). Infarct size was assessed by a dual staining method with triphenyltetrazolium chloride and Evans blue. Blood flow measurements in the subendocardial region were made by infusion of coloured microspheres before occlusion and midway through the sustained occlusion. Transcardiac alteration of neutrophillic function was assessed by luminol-enhanced whole blood chemiluminescence induced by zymosan. RESULTS: Infarct size was significantly reduced in the preconditioned dogs [12.5(SEM 4.0)%, n = 10, p < 0.01] compared with the control dogs [40.5(6.1)%, n = 10], an effect significantly reduced by the 8-PT treatment [23.4(4.9)%, n = 8]. Treatment with 8-PT without ischaemic preconditioning had no effect on infarct size [42.8(6.3)%, n = 7]. There was no difference in myocardial blood flow in the ischaemic or non-ischaemic subendocardial tissue between any pair of the four groups. The ratio of whole blood chemiluminescence in the cardiac vein to that in the carotid artery was considerably reduced in preconditioned dogs compared with that in control dogs after reperfusion. Myeloperoxidase activity in the ischaemic myocardium and the peripheral neutrophil count at the end of the experiment were both also decreased compared with control dogs. In preconditioned dogs treated with 8-PT, neutrophillic function in the coronary circulation after reperfusion was increased compared with that in both controls and preconditioned dogs with no 8-PT treatment. There was no difference in neutrophillic function between the 8-PT-treated dogs with or without ischaemic preconditioning. Treatment with 8-PT increased myeloperoxidase activity in the ischaemic myocardium of the preconditioned dogs, and no difference was seen in activity between dogs treated with 8-PT with or without ischaemic preconditioning. CONCLUSIONS: An adenosine receptor blocker caused a moderate but significant reversal of infarct limitation by ischaemic preconditioning associated with a significant increase of neutrophillic function in the coronary circulation during early reperfusion.


Subject(s)
Myocardial Infarction/prevention & control , Myocardial Ischemia/metabolism , Purinergic P1 Receptor Antagonists , Theophylline/analogs & derivatives , Animals , Dogs , Female , Leukocyte Count , Male , Myocardial Infarction/pathology , Myocardium/pathology , Neutrophils/cytology , Neutrophils/physiology , Peroxidase/metabolism , Theophylline/pharmacology
15.
Jpn J Physiol ; 44 Suppl 2: S219-26, 1994.
Article in English | MEDLINE | ID: mdl-7752528

ABSTRACT

The inhibitory pathway of cardiac cAMP-dependent protein kinase regulated Cl- conductance was investigated using the whole-cell configuration of patch-clamp techniques in single guinea pig ventricular myocytes. Pertussis toxin-sensitive G proteins (Gi), mediating the signal transductions between muscarinic receptors and adenylate cyclase, have a substantial tonic activity even in the absence of muscarinic receptor modulators. Muscarinic agonists or antagonists (like atropine) either increase or decrease this basal activity of Gi by altering the proportion of active and inactive forms of the receptors. Similar to L-type Ca-channel currents, the Cl- conductance showed a transient over-recovery upon cessation of brief muscarinic receptor stimulation by carbachol (CCh) (rebound). Atropine alone enhanced the Cl- conductance elicited by low concentrations of Iso (reverse agonist). After washout of atropine, the over-suppression of the conductance was observed as a mirror image of CCh-induced rebound (reverse rebound). Both types of rebound became prominent when cell dialysis with pipette solutions containing 100 microM GTP was minimized with high-resistance pipettes. Endogenous GTP is therefore an intracellular modulator, and not simply a mediator, of Gi-dependent signal transduction.


Subject(s)
Adenylate Cyclase Toxin , Chloride Channels/physiology , Heart/drug effects , Pertussis Toxin , Virulence Factors, Bordetella/toxicity , Animals , Colforsin/pharmacology , Cyclic AMP-Dependent Protein Kinases/pharmacology , Dose-Response Relationship, Drug , GTP-Binding Proteins , Guinea Pigs , Isoproterenol/pharmacology , Patch-Clamp Techniques
16.
Circ Res ; 72(6): 1293-9, 1993 Jun.
Article in English | MEDLINE | ID: mdl-8495557

ABSTRACT

The infarct-limiting effect of ischemic preconditioning is believed to be a transient phenomenon. We examined the delayed effects of repetitive brief ischemia on limiting infarct size in an open-chest dog model by an occlusion (90 minutes) of the left anterior descending coronary artery (LAD) followed by reperfusion (5 hours). The dogs were preconditioned with four brief repeated ischemic episodes induced by 5-minute LAD occlusions with subsequent reperfusion. The size of infarcts initiated by a sustained occlusion immediately or 24 hours after preconditioning was significantly smaller when compared with infarcts in sham-operated dogs (for the immediate occlusion, 14.4 +/- 2.0% versus 39.0 +/- 3.7%, respectively [p < 0.01]; and for the delayed occlusion, 18.8 +/- 3.4% versus 35.1 +/- 4.6%, respectively [p < 0.05]); however, when the infarction was induced 3 hours (31.2 +/- 3.7% versus 37.5 +/- 4.2%, respectively) or 12 hours (25.4 +/- 4.8% versus 35.0 +/- 5.3%, respectively) after repetitive ischemia, the infarct size did not differ. No differences were seen in regional myocardial blood flow or rate-pressure products between the two groups. These results indicate that an infarct-limiting effect of brief repeated ischemia can be observed 24 hours after sublethal preconditioning.


Subject(s)
Myocardial Ischemia/physiopathology , Myocardial Reperfusion Injury/physiopathology , Animals , Coronary Circulation , Disease Models, Animal , Disease Susceptibility , Dogs , Female , Hemodynamics , Male , Myocardial Infarction/pathology , Myocardial Infarction/physiopathology , Time Factors
17.
Cardiovasc Res ; 27(6): 1056-60, 1993 Jun.
Article in English | MEDLINE | ID: mdl-8221764

ABSTRACT

OBJECTIVE: The role of arachidonate lipoxygenase activity in reoxygenation induced cell injury in adult canine cardiac myocytes was investigated. METHODS: The production of hydroxyeicosatetraenoic acids (HETEs), which are lipoxygenase metabolites, was measured with high pressure liquid chromatography in canine cardiac myocytes cultured under hypoxic conditions and then reoxygenated. Free radical generation was evaluated by electron paramagnetic resonance spectroscopy with a spin trapper, 5,5-dimethyl-1-pyrroline N-oxide (DMPO) and luminol enhanced chemiluminescence emission. Cell injury was estimated in terms of morphological changes and release of intracellular enzymes. Morphological damage to myocytes was quantified in terms of the percentage of hypercontracted "round" cells. The effects of nordihydroguaiaretic acid, AA-861, mepacrine, indomethacin, aspirin, alpha tocopherol, and 2-0-octadecylascorbic acid (CV-3611) on lipoxygenase metabolism, free radical generation and cell injury were also assessed. RESULTS: Cardiac myocytes produced 5-HETE and 12-HETE at less than 0.1 ng.mg-1 protein under normoxic conditions. Production of HETE was greatly increased at five hours of reoxygenation after 45 minutes of hypoxia [5-HETE = 12.0(SEM 0.5), 12-HETE = 23.6(1.1) ng.mg-1 protein]. Both DMPO-OH adduct generation and chemiluminescence emission were considerably increased after one to three hours of reoxygenation, although they increased only slightly after 45 minutes of hypoxia. After five hours of reoxygenation, long rod cells gradually became deformed; 92.0% of the cells were converted to hypercontracted "round" cells. Cell injury and HETE production were significantly suppressed by nordihydroguaiaretic acid (10 microM), AA-861 (2 microM), and mepacrine (10 microM). Indomethacin (10 microM) and aspirin (50 microM) enhanced cell injury and HETE production. alpha Tocopherol and CV-3611 greatly suppressed cell injury and free radical generation, but not HETE production. CONCLUSION: The arachidonate lipoxygenase metabolic pathway may have an important role in reoxygenation induced myocardial cell injury in adult cardiac myocytes, possibly because of the generation of free radicals.


Subject(s)
Arachidonate Lipoxygenases/metabolism , Hypoxia/metabolism , Myocardial Reperfusion Injury/metabolism , Myocardium/metabolism , Oxygen/physiology , Animals , Cells, Cultured , Cyclic N-Oxides/metabolism , Dogs , Free Radicals/metabolism , Hydroxyeicosatetraenoic Acids/biosynthesis , Hypoxia/pathology , Myocardium/pathology
18.
Cardiovasc Res ; 27(3): 377-83, 1993 Mar.
Article in English | MEDLINE | ID: mdl-8490937

ABSTRACT

OBJECTIVE: The aim was to define the relation between transcardiac changes in neutrophil function in myocardial ischaemia and the progression of myocardial necrosis. METHODS: Samples of blood from carotid artery, jugular vein, and cardiac vein streaming from the ischaemic area were taken simultaneously in a canine coronary occlusion-reperfusion model of myocardial infarction. Neutrophil function was evaluated by neutrophil count, whole blood chemiluminescence and leucocyte infiltration into the ischaemic myocardium. Myocardial necrosis was assessed by plasma creatine kinase and dual staining technique using Evans blue dye and triphenyltetrazolium chloride. Effects of a free radical scavenger, N-2-mercaptopropionyl glycine (MPG), initiated 15 min before reperfusion and continued during the reperfusion phase, were also examined. RESULTS: Whole blood chemiluminescence of the cardiac vein was reduced at 90 min after coronary artery occlusion as compared to carotid artery [5.8(SEM 0.5) v 7.5(0.7) count x 10(3) cell neutrophil-1 x 10 min-1, p < 0.05], and then increased abruptly after reperfusion to peak after 10 min of reperfusion [7.1(0.7) count x 10(3) cell neutrophil-1 x 10 min-1]. The neutrophil count in cardiac venous blood was significantly reduced within 5 min of reperfusion. MPG significantly attenuated the reperfusion associated increase in cardiac vein whole blood chemiluminescence and the decrease in the cardiac venous blood neutrophil count. The increase in myocardial free radical generation 1-3 h after reperfusion, as assessed by the electron paramagnetic resonance spin trapping technique, was reduced markedly, as was the extent of leucocyte infiltration into the ischaemic myocardium. Under these conditions, administration of MPG significantly reduced myocardial infarct size [40.3(4.5)% v 21.4(4.2)%, p < 0.05]. A marked increase in transcardiac creatine kinase release after reperfusion observed in control dogs was also reduced significantly. CONCLUSIONS: A transient alteration of neutrophil function occurs in the coronary circulation immediately after reperfusion, which may augment neutrophil infiltration and free radical generation in the ischaemic myocardium, leading to the propagation of myocardial ischaemia/reperfusion injury.


Subject(s)
Myocardial Ischemia/blood , Myocardial Reperfusion Injury/blood , Neutrophils/physiology , Animals , Blood Pressure , Carotid Arteries , Coronary Vessels , Creatine Kinase/blood , Dogs , Female , Free Radicals/metabolism , Heart Rate , Leukocyte Count , Luminescent Measurements , Male , Myocardial Ischemia/enzymology , Myocardial Reperfusion Injury/enzymology , Myocardium/metabolism , Time Factors , Tiopronin/pharmacology
19.
Heart Vessels ; 8(3): 115-20, 1993.
Article in English | MEDLINE | ID: mdl-8407720

ABSTRACT

This study examined whether brief repeated myocardial ischemia altered free radical generating and scavenging activity in a dog model. In dogs preconditioned with four 5-min left anterior descending coronary artery (LAD) occlusions and reperfusions, we examined transcardiac changes in both the function of neutrophils, cells which are major free radical generators, and in myocardial antioxidant enzyme activity, as an indication of free radical scavenging. Neutrophil function was assessed by determining luminol-enhanced whole blood chemiluminescence (CL) induced by zymosan. Blood was taken simultaneously from the carotid artery and the cardiac vein running along the occluded LAD. Preconditioning with sublethal ischemia significantly reduced whole blood CL in the cardiac vein compared with the carotid artery after the first and fourth 5-min reperfusions, while there was no difference in neutrophil count between these sampling sites. Immediately after brief repeated ischemia and reperfusion, manganese-superoxide dismutase (SOD) activity was significantly enhanced, and glutathione reductase activity was markedly reduced in the ischemic, compared with the non-ischemic, myocardium. There were no differences in the myocardial activities of copper, zinc-SOD, glutathione peroxidase, and glutathione S-transferase between the ischemic and non-ischemic regions. Also, no difference was observed between the reduced myocardial glutathione levels in these regions, although the oxidized glutathione level was significantly higher in the ischemic regions of the subepicardial and subendocardial areas. We demonstrated that brief repeated ischemia affects free radical generating and scavenging systems in the ischemic myocardium.


Subject(s)
Free Radical Scavengers , Myocardial Ischemia/physiopathology , Reactive Oxygen Species/metabolism , Animals , Dogs , Female , Free Radicals , Glutathione/metabolism , Glutathione Peroxidase/physiology , Glutathione Transferase/physiology , Luminescent Measurements , Male , Myocardial Infarction/physiopathology , Myocardium/enzymology , Neutrophils/physiology , Oxidation-Reduction , Superoxide Dismutase/physiology
20.
Am J Physiol ; 264(1 Pt 2): H33-9, 1993 Jan.
Article in English | MEDLINE | ID: mdl-8430858

ABSTRACT

We examined antioxidant activity in the pre-conditioned canine myocardium with four 5-min episodes of regional ischemia and reperfusion. Immediately after repetitive brief ischemia, mitochondrial Mn-superoxide dismutase (SOD) activity in the ischemic myocardium significantly increased compared with that in the nonischemic myocardium (18.7 +/- 2.1 vs. 14.9 +/- 1.0 U/mg protein, P < 0.05). Although no difference was seen in the activity between these regions after 3 h of the sublethal ischemia, a significant increase in the activity of the ischemic myocardium reappeared after 24 h compared with that of the nonischemic myocardium (26.7 +/- 0.9 vs. 20.8 +/- 0.9 U/mg protein, P < 0.05). Mn-SOD content increased gradually in the ischemic myocardium after sublethal ischemia, with a peak after 24 h (2.8 +/- 0.1 vs. 2.1 +/- 0.1 microgram/mg protein, P < 0.05). There were no differences in the activity and content of Cu, Zn-SOD between these regions after sublethal ischemia. Activities of glutathione peroxidase and reductase were significantly higher and lower, respectively, in the ischemic myocardium than those of the nonischemic myocardium immediately after repetitive brief ischemia, but no differences between these regions were seen in activities after 3 or 24 h. These results indicate that a brief ischemic insult alters myocardial antioxidant activity not only immediately after but also 24 h after sublethal ischemia.


Subject(s)
Coronary Disease/enzymology , Glutathione Peroxidase/metabolism , Glutathione Reductase/metabolism , Myocardium/enzymology , Superoxide Dismutase/metabolism , Animals , Dogs , Female , Male , Reference Values , Reperfusion , Time Factors
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