Neuronal Vacuolization and Necrosis Induced by the Noncompetitive N-methyl-d-aspartate (NMDA) Antagonist MK(+)801 (Dizocilpine Maleate): A Light and Electron Microscopic Evaluation of the Rat Retrosplenial Cortex

1993 ◽  
Vol 123 (2) ◽  
pp. 204-215 ◽  
Author(s):  
Andrew S. Fix ◽  
Jeffrey W. Horn ◽  
Karen A. Wightman ◽  
Charles A. Johnson ◽  
Gerald G. Long ◽  
...  
Keyword(s):  
Nmda Antagonist ◽  
Retrosplenial Cortex ◽  
Electron Microscopic ◽  
Mk 801 ◽  
Microscopic Evaluation

scholarly journals Isoflurane and Propofol Block Neurotoxicity Caused by MK-801 in the Rat Posterior Cingulate/Retrosplenial Cortex

1997 ◽  
Vol 17 (2) ◽  
pp. 168-174 ◽  
Author(s):  
Vesna Jevtović-Todorović ◽  
Charity O. Kirby ◽  
John W. Olney
Keyword(s):  
Brain Injury ◽  
Neuronal Degeneration ◽  
Nmda Antagonist ◽  
Retrosplenial Cortex ◽  
Acute Brain Injury ◽  
Nmda Antagonists ◽  
General Anesthetics ◽  
General Anesthetic ◽  
Mk 801 ◽  
Anesthetic Agents

In acute brain injury syndromes, the potent N-methyl-D-aspartate (NMDA) antagonist, MK-801, can prevent neuronal degeneration, and the general anesthetics, isoflurane and propofol, may also provide neuroprotective benefits. An obstacle to the use of NMDA antagonists for neuroprotective purposes is that they can cause a neurotoxic vacuole reaction in cerebrocortical neurons. This study demonstrates the ability of isoflurane and propofol to prevent the neurotoxic vacuole reaction induced by MK-801. Low sedative doses of inhaled isoflurane (1%) or intravenous (i.v.) propofol (7.5 mg/kg/h) were as effective as higher general anesthetic doses. Thus, in the clinical management of acute brain injury conditions such as stroke and brain trauma, administration of one of these anesthetic agents together with an NMDA antagonist may be an excellent formula for obtaining optimal neuroprotection while eliminating serious side effects.

TEM comparison of osmium vs osmium with potassium ferricyanide secondary fixatives and the impact of secondary fixative temperature on tissue preservation/contrast quality

1996 ◽  
Vol 54 ◽  
pp. 910-911
Author(s):  
J. W. Horn ◽  
B. J. Dovey-Hartman ◽  
V. P. Meador
Keyword(s):  
Osmium Tetroxide ◽  
Potassium Ferricyanide ◽  
Electron Microscopic ◽  
Transmission Electron ◽  
Microscopic Evaluation ◽  
Cacodylate Buffer ◽  
Transmission Electron Microscopic ◽  
Glutaraldehyde Solution ◽  
Temperature Impact ◽  
The Impact

Osmium tetroxide (OsO4) is a universally used secondary fixative for routine transmission electron microscopic evaluation of biological specimens. Use of OsO4 results in good ultrastructural preservation and electron density but several factors, such as concentration, length of exposure, and temperature, impact overall results. Potassium ferricyanide, an additive used primarily in combination with OsO4, has mainly been used to enhance the contrast of lipids, glycogen, cell membranes, and membranous organelles. The purpose of this project was to compare the secondary fixative solutions, OsO4 vs. OsO4 with potassium ferricyanide, and secondary fixative temperature for determining which combination gives optimal ultrastructural fixation and enhanced organelle staining/contrast.Fresh rat liver samples were diced to ∼1 mm3 blocks, placed into porous processing capsules/baskets, preserved in buffered 2% formaldehyde/2.5% glutaraldehyde solution, and rinsed with 0.12 M cacodylate buffer (pH 7.2). Tissue processing capsules were separated (3 capsules/secondary fixative.solution) and secondarily fixed (table) for 90 minutes. Tissues were buffer rinsed, dehydrated with ascending concentrations of ethanol solutions, infiltrated, and embedded in epoxy resin.

Evaluation of platelet dense granules for determining storage pool deficiencies by HVEM image and quantitative analysis

1996 ◽  
Vol 54 ◽  
pp. 770-771
Author(s):  
W.T. Gunning ◽  
J.N. Turner ◽  
K. Buttle ◽  
E.P. Calomeni ◽  
N.A. Lachant ◽  
...  
Keyword(s):  
Quantitative Analysis ◽  
Platelet Function ◽  
Electron Microscopic ◽  
Von Willebrand's Disease ◽  
Dense Granules ◽  
Storage Pool ◽  
Prolonged Bleeding ◽  
Microscopic Evaluation ◽  
Storage Pools ◽  
Electron Lucent

There are a variety of conditions which have been associated with prolonged bleeding times. If other etiologies including von Willebrand's disease have been ruled out, a platelet function disorder must be considered. The best, if not only, technique to make this diagnosis is the electron microscopic evaluation of whole air dried platelets. Bull first described the presence of dense granules in whole platelets in 1968 and the technique has been utilized extensively The electron dense or delta granules are easily distinguished from the larger more numerous alpha granules which are electron lucent. The significance of the dense granules is that they are known to be “storage pools” of serotonin, calcium, adenosine di- and triphosphate, and pyrophosphate. Prolonged bleeding times may be directly related to an insufficiency of these substances. The diagnosis of a storage pool deficiency is made when either the storage content of the dense granules is abnormal or their number is diminished. We observe normal platelets to have 4-6 dense granules, which agrees with the literature.

INTERACTION BETWEEN THE NONCOMPETITIVE NMDA ANTAGONIST MK-801 AND MORPHINE: EVALUATION BY AMBULATORY ACTIVITY IN MICE.

1992 ◽  
Vol 15 ◽  
pp. 635B
Author(s):  
Y. Iijima ◽  
T. Asami ◽  
H. Kuribara ◽  
I. Ida ◽  
T. Higuchi ◽  
...  
Keyword(s):  
Nmda Antagonist ◽  
Ambulatory Activity ◽  
Mk 801

scholarly journals Ketamine effects on anxiety and fear-related behaviors: current literature evidence and new findings

2019 ◽  
Author(s):  
Gabriela P. Silote ◽  
Sabrina F.S. de Oliveira ◽  
Deidiane E. Ribeiro ◽  
Mayara S. Machado ◽  
Roberto Andreatini ◽  
...  
Keyword(s):  
Nmda Antagonist ◽  
Inhibitory Avoidance ◽  
Nmda Receptor Antagonist ◽  
Mixed Effects ◽  
Antidepressant Effect ◽  
List Type ◽  
Mk 801 ◽  
New Findings ◽  
Male Wistar Rats ◽  
Animal Tests

AbstractKetamine, a non-competitive N-methyl-D-aspartate (NMDA) receptor antagonist, presents rapid and sustained antidepressant effect in clinical and preclinical studies. Regarding ketamine effects on anxiety, there is a widespread discordance among pre-clinical studies. To address this issue, the present study reviewed the literature (electronic database MEDLINE) to summarize the profile of ketamine effects in animal tests of anxiety/fear. We found that ketamine anxiety/fear-related effects may depend on the anxiety paradigm, schedule of ketamine administration and tested species. Moreover, there was no report of ketamine effects in animal tests of fear related to panic disorder (PD). Based on that finding, we evaluated if treatment with ketamine and another NMDA antagonist, MK-801, would induce acute and sustained (24 hours later) anxiolytic and/or panicolytic-like effects in animals exposed to the elevated T-maze (ETM). The ETM evaluates, in the same animal, conflict-evoked and fear behaviors, which are related, respectively, to generalized anxiety disorder and PD. Male Wistar rats were systemically treated with racemic ketamine (10, 30 and 80 mg/kg) or MK-801 (0.05 and 0.1 mg/kg) and tested in the ETM in the same day or 24 hours after their administration. Ketamine did not affect the behavioral tasks performed in the ETM acutely or 24 h later. MK-801 impaired inhibitory avoidance in the ETM only at 45 min post-injection, suggesting a rapid but not sustained anxiolytic-like effect. Altogether our results suggest that ketamine might have mixed effects in anxiety tests while it does not affect panic-related behaviors.HighlightsKetamine induces mixed effects in animal anxiety testsFew studies investigated the individual effects of S-ketamine in anxiety/fear testsNone study evaluated the effects of R-Ketamine on anxiety/fear-related behaviorsSystemic ketamine does not affect panic-like behaviors in the elevated T-maze

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