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Kenji Ogli - One of the best experts on this subject based on the ideXlab platform.

  • possible participation of nmda and glycine receptors but not gabaa receptors in enflurane induced Opisthotonus in mice
    Clinical and Experimental Pharmacology and Physiology, 1994
    Co-Authors: Hisao Komatsu, Satoshi Yokono, Junko Nogaya, Masaaki Ueki, Kenji Ogli
    Abstract:

    SUMMARY 1. We previously reported that volatile anaesthetics produce incidences of a transient Opisthotonus in mice, a sign of CNS stimulation. This study was performed to investigate mechanisms by which enflurane-induced Opisthotonus (EIO) occurs. 2. The effects of pretreatment of N-methyl-d-aspartate (NMDA) antagonists dizocilpine (MK-801; DIZ) and ketamine (KET), GABAA antagonists picrotoxin (PIC), pentylenetetrazol (PTZ) and glycine antagonist strychnine (STR) on the incidence of EIO were determined. Prior to exposure to 2.0% enflurane in air, male ddN mice were given intraperitoneal injections of 0.2 mL saline (control), 0.5–5.0 mg/kg DIZ, 20–80 mg/kg KET, 2.9 mg/kg PIC, 40.0 mg/kg PTZ and 0.75 mg/kg STR. After the injection, the behavioural state of the mice was observed for 20 min (the pre-enflurane period). During the exposure to enflurane the time for immobilization, that is, anaesthetic induction time (IT), and the incidence of EIO were measured. 3. Dizocilpine (1.0–5.0 mg/kg) and KET (80 mg/kg) significantly (P<0.01) reduced both the incidence of EIO and IT in a dose-dependent manner. During the pre-enflurane period DIZ produced incidences (5–40%) of transient seizures in a dose-dependent manner, while KET did not induce them at all. The two GABAa antagonists had no detectable effect on the EIO. Strychnine significantly enhanced the EIO. These CNS stimulants resulted in a 3–10% incidence of transient seizure and/or Opisthotonus during the pre-enflurane period, but there was no correlation between DIZ-induced seizure and EIO. 4. These results suggest that the EIO is mediated by the NMDA and the STR-sensitive glycine receptors, but not the GABAA receptor. We speculate that DIZ acts on the NMDA-receptor and/or disrupts the balance between the inhibitory and the excitatory systems.

  • Possible participation of NMDA and glycine receptors but not GABAA receptors in enflurane-induced Opisthotonus in mice
    Clinical and Experimental Pharmacology and Physiology, 1994
    Co-Authors: Hisao Komatsu, Satoshi Yokono, Junko Nogaya, Masaaki Ueki, Kenji Ogli
    Abstract:

    SUMMARY 1. We previously reported that volatile anaesthetics produce incidences of a transient Opisthotonus in mice, a sign of CNS stimulation. This study was performed to investigate mechanisms by which enflurane-induced Opisthotonus (EIO) occurs. 2. The effects of pretreatment of N-methyl-d-aspartate (NMDA) antagonists dizocilpine (MK-801; DIZ) and ketamine (KET), GABAA antagonists picrotoxin (PIC), pentylenetetrazol (PTZ) and glycine antagonist strychnine (STR) on the incidence of EIO were determined. Prior to exposure to 2.0% enflurane in air, male ddN mice were given intraperitoneal injections of 0.2 mL saline (control), 0.5–5.0 mg/kg DIZ, 20–80 mg/kg KET, 2.9 mg/kg PIC, 40.0 mg/kg PTZ and 0.75 mg/kg STR. After the injection, the behavioural state of the mice was observed for 20 min (the pre-enflurane period). During the exposure to enflurane the time for immobilization, that is, anaesthetic induction time (IT), and the incidence of EIO were measured. 3. Dizocilpine (1.0–5.0 mg/kg) and KET (80 mg/kg) significantly (P

  • the n methyl d aspartate nmda receptor antagonist dizocilpine mk 801 suppresses enflurane induced Opisthotonus in mice
    Journal of Anesthesia, 1993
    Co-Authors: Hisao Komatsu, Junko Nogaya, Daisuke Anabuki, Kenji Ogli
    Abstract:

    We determined whether enflurane-induced Opisthotonus in ddN mice is mediated by N-methyl-D-aspartate (NMDA) receptor using NMDA receptor antagonists dizocilpine (MK-801) and ketamine. Animals were given intraperitoneal injections of 0.2 ml saline (control), 2.5 or 5.0 mgkg−1 dizocilpine in saline, or 20 or 40 mgkg−1 ketamine in saline 20 min prior to exposure to 2.0% enflurane. Incidence of Opisthotonus measured during exposure to enflurane for 20 min was 49% (n=51) in saline (control) group, 6.7 (P < 0.01 vs control, n=30) and 15.0% (P < 0.01, n=40) in 2.5 and 5.0 mgkg−1 dizocilpine group, respectively, and 43.9 (NS, n=41) and 40.0% (NS, n=40) in 20 and 40 mgkg−1 ketamine group, respectively. These results strongly suggest that enflurane-induced Opisthotonus is mediated by NMDA receptor. Ketamine failed to suppress significantly due to possibly small dosages. Further, dizocilpine itself produced severe seizures during preenflurane period (30.0 and 40.0% in 2.5 and 5.0 mgkg−1 , respectively), which may be a novel finding.

  • The effects of age and anesthetic solubility on anesthetic-induced Opisthotonus in mice
    Journal of Anesthesia, 1991
    Co-Authors: Hisao Komatsu, Satoshi Yokono, Tomoko Ohara, Junko Nogaya, Ikuko Tsukamoto, Kenji Ogli
    Abstract:

    In our previous report which indicated volatile anesthetics-induced Opisthotonus in mice, we hypothesized that Opisthotonus might relate with the rapidity of anesthetic induction, i.e., the blood/gas partition coefficient of the agent. To confirm this, we determined the incidence of Opisthotonus induced by four different halogenated ethers (2.0% sevoflurane, 1.3% isoflurane, 2.0% enflurane, and 0.5% methoxyflurane) and 1.0% halothane, a haloalkane, in male ddN mice. The effect of age on Opisthotonus was also evaluated by using young (10±2 weeks), middle-aged (6±1 months), and elderly (12±1 months) groups of male ddN mice. In each age group, the incidence of Opisthotonus occurred in the following order: sevoflurane > isoflurane > enflurane > methoxyflurane > halothane. This partly supports our hypothesis as far as halogenated ethers are concerned. Halothane rarely produced Opisthotonus. In the sevoflurane, isoflurane, and methoxyflurane groups, incidence was lower in middle-aged than in young or elderly mice, while incidence increased with age in the enflurane group.

Hisao Komatsu - One of the best experts on this subject based on the ideXlab platform.

  • possible participation of nmda and glycine receptors but not gabaa receptors in enflurane induced Opisthotonus in mice
    Clinical and Experimental Pharmacology and Physiology, 1994
    Co-Authors: Hisao Komatsu, Satoshi Yokono, Junko Nogaya, Masaaki Ueki, Kenji Ogli
    Abstract:

    SUMMARY 1. We previously reported that volatile anaesthetics produce incidences of a transient Opisthotonus in mice, a sign of CNS stimulation. This study was performed to investigate mechanisms by which enflurane-induced Opisthotonus (EIO) occurs. 2. The effects of pretreatment of N-methyl-d-aspartate (NMDA) antagonists dizocilpine (MK-801; DIZ) and ketamine (KET), GABAA antagonists picrotoxin (PIC), pentylenetetrazol (PTZ) and glycine antagonist strychnine (STR) on the incidence of EIO were determined. Prior to exposure to 2.0% enflurane in air, male ddN mice were given intraperitoneal injections of 0.2 mL saline (control), 0.5–5.0 mg/kg DIZ, 20–80 mg/kg KET, 2.9 mg/kg PIC, 40.0 mg/kg PTZ and 0.75 mg/kg STR. After the injection, the behavioural state of the mice was observed for 20 min (the pre-enflurane period). During the exposure to enflurane the time for immobilization, that is, anaesthetic induction time (IT), and the incidence of EIO were measured. 3. Dizocilpine (1.0–5.0 mg/kg) and KET (80 mg/kg) significantly (P<0.01) reduced both the incidence of EIO and IT in a dose-dependent manner. During the pre-enflurane period DIZ produced incidences (5–40%) of transient seizures in a dose-dependent manner, while KET did not induce them at all. The two GABAa antagonists had no detectable effect on the EIO. Strychnine significantly enhanced the EIO. These CNS stimulants resulted in a 3–10% incidence of transient seizure and/or Opisthotonus during the pre-enflurane period, but there was no correlation between DIZ-induced seizure and EIO. 4. These results suggest that the EIO is mediated by the NMDA and the STR-sensitive glycine receptors, but not the GABAA receptor. We speculate that DIZ acts on the NMDA-receptor and/or disrupts the balance between the inhibitory and the excitatory systems.

  • Possible participation of NMDA and glycine receptors but not GABAA receptors in enflurane-induced Opisthotonus in mice
    Clinical and Experimental Pharmacology and Physiology, 1994
    Co-Authors: Hisao Komatsu, Satoshi Yokono, Junko Nogaya, Masaaki Ueki, Kenji Ogli
    Abstract:

    SUMMARY 1. We previously reported that volatile anaesthetics produce incidences of a transient Opisthotonus in mice, a sign of CNS stimulation. This study was performed to investigate mechanisms by which enflurane-induced Opisthotonus (EIO) occurs. 2. The effects of pretreatment of N-methyl-d-aspartate (NMDA) antagonists dizocilpine (MK-801; DIZ) and ketamine (KET), GABAA antagonists picrotoxin (PIC), pentylenetetrazol (PTZ) and glycine antagonist strychnine (STR) on the incidence of EIO were determined. Prior to exposure to 2.0% enflurane in air, male ddN mice were given intraperitoneal injections of 0.2 mL saline (control), 0.5–5.0 mg/kg DIZ, 20–80 mg/kg KET, 2.9 mg/kg PIC, 40.0 mg/kg PTZ and 0.75 mg/kg STR. After the injection, the behavioural state of the mice was observed for 20 min (the pre-enflurane period). During the exposure to enflurane the time for immobilization, that is, anaesthetic induction time (IT), and the incidence of EIO were measured. 3. Dizocilpine (1.0–5.0 mg/kg) and KET (80 mg/kg) significantly (P

  • the n methyl d aspartate nmda receptor antagonist dizocilpine mk 801 suppresses enflurane induced Opisthotonus in mice
    Journal of Anesthesia, 1993
    Co-Authors: Hisao Komatsu, Junko Nogaya, Daisuke Anabuki, Kenji Ogli
    Abstract:

    We determined whether enflurane-induced Opisthotonus in ddN mice is mediated by N-methyl-D-aspartate (NMDA) receptor using NMDA receptor antagonists dizocilpine (MK-801) and ketamine. Animals were given intraperitoneal injections of 0.2 ml saline (control), 2.5 or 5.0 mgkg−1 dizocilpine in saline, or 20 or 40 mgkg−1 ketamine in saline 20 min prior to exposure to 2.0% enflurane. Incidence of Opisthotonus measured during exposure to enflurane for 20 min was 49% (n=51) in saline (control) group, 6.7 (P < 0.01 vs control, n=30) and 15.0% (P < 0.01, n=40) in 2.5 and 5.0 mgkg−1 dizocilpine group, respectively, and 43.9 (NS, n=41) and 40.0% (NS, n=40) in 20 and 40 mgkg−1 ketamine group, respectively. These results strongly suggest that enflurane-induced Opisthotonus is mediated by NMDA receptor. Ketamine failed to suppress significantly due to possibly small dosages. Further, dizocilpine itself produced severe seizures during preenflurane period (30.0 and 40.0% in 2.5 and 5.0 mgkg−1 , respectively), which may be a novel finding.

  • The effects of age and anesthetic solubility on anesthetic-induced Opisthotonus in mice
    Journal of Anesthesia, 1991
    Co-Authors: Hisao Komatsu, Satoshi Yokono, Tomoko Ohara, Junko Nogaya, Ikuko Tsukamoto, Kenji Ogli
    Abstract:

    In our previous report which indicated volatile anesthetics-induced Opisthotonus in mice, we hypothesized that Opisthotonus might relate with the rapidity of anesthetic induction, i.e., the blood/gas partition coefficient of the agent. To confirm this, we determined the incidence of Opisthotonus induced by four different halogenated ethers (2.0% sevoflurane, 1.3% isoflurane, 2.0% enflurane, and 0.5% methoxyflurane) and 1.0% halothane, a haloalkane, in male ddN mice. The effect of age on Opisthotonus was also evaluated by using young (10±2 weeks), middle-aged (6±1 months), and elderly (12±1 months) groups of male ddN mice. In each age group, the incidence of Opisthotonus occurred in the following order: sevoflurane > isoflurane > enflurane > methoxyflurane > halothane. This partly supports our hypothesis as far as halogenated ethers are concerned. Halothane rarely produced Opisthotonus. In the sevoflurane, isoflurane, and methoxyflurane groups, incidence was lower in middle-aged than in young or elderly mice, while incidence increased with age in the enflurane group.

Kailash P Bhatia - One of the best experts on this subject based on the ideXlab platform.

  • dystonic Opisthotonus a red flag for neurodegeneration with brain iron accumulation syndromes
    Movement Disorders, 2013
    Co-Authors: Maria Stamelou, Annu Aggarwal, Susanne A Schneider, Henry Houlden, Amit Batla, Chin Song Lu, Mohit Bhatt, Kailash P Bhatia
    Abstract:

    Back arching was reported in one of the very first patients with neurodegeneration with brain iron accumulation syndrome (NBIAs) published in 1936. However, recent reports have mainly focused on the genetic and imaging aspects of these disorders, and the phenotypic characterization of the dystonia has been lost. In evaluating patients with NBIAs in our centers, we have observed that action-induced dystonic Opisthotonus is a common and characteristic feature of NBIAs. Here, we present a case series of patients with NBIAs presenting this feature demonstrated by videos. We suggest that dystonic Opisthotonus could be a useful “red flag” for clinicians to suspect NBIAs, and we discuss the differential diagnosis of this feature. This would be particularly useful in identifying patients with NBIAs and no iron accumulation as yet on brain imaging (for example, as in phospholipase A2, group IV (cytosolic, calcium-independent) [PLA2G6]-related disorders), and it has management implications. © 2013 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.

Susanne A Schneider - One of the best experts on this subject based on the ideXlab platform.

  • dystonic Opisthotonus a red flag for neurodegeneration with brain iron accumulation syndromes
    Movement Disorders, 2013
    Co-Authors: Maria Stamelou, Annu Aggarwal, Susanne A Schneider, Henry Houlden, Amit Batla, Chin Song Lu, Mohit Bhatt, Kailash P Bhatia
    Abstract:

    Back arching was reported in one of the very first patients with neurodegeneration with brain iron accumulation syndrome (NBIAs) published in 1936. However, recent reports have mainly focused on the genetic and imaging aspects of these disorders, and the phenotypic characterization of the dystonia has been lost. In evaluating patients with NBIAs in our centers, we have observed that action-induced dystonic Opisthotonus is a common and characteristic feature of NBIAs. Here, we present a case series of patients with NBIAs presenting this feature demonstrated by videos. We suggest that dystonic Opisthotonus could be a useful “red flag” for clinicians to suspect NBIAs, and we discuss the differential diagnosis of this feature. This would be particularly useful in identifying patients with NBIAs and no iron accumulation as yet on brain imaging (for example, as in phospholipase A2, group IV (cytosolic, calcium-independent) [PLA2G6]-related disorders), and it has management implications. © 2013 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.

Chin Song Lu - One of the best experts on this subject based on the ideXlab platform.

  • dystonic Opisthotonus a red flag for neurodegeneration with brain iron accumulation syndromes
    Movement Disorders, 2013
    Co-Authors: Maria Stamelou, Annu Aggarwal, Susanne A Schneider, Henry Houlden, Amit Batla, Chin Song Lu, Mohit Bhatt, Kailash P Bhatia
    Abstract:

    Back arching was reported in one of the very first patients with neurodegeneration with brain iron accumulation syndrome (NBIAs) published in 1936. However, recent reports have mainly focused on the genetic and imaging aspects of these disorders, and the phenotypic characterization of the dystonia has been lost. In evaluating patients with NBIAs in our centers, we have observed that action-induced dystonic Opisthotonus is a common and characteristic feature of NBIAs. Here, we present a case series of patients with NBIAs presenting this feature demonstrated by videos. We suggest that dystonic Opisthotonus could be a useful “red flag” for clinicians to suspect NBIAs, and we discuss the differential diagnosis of this feature. This would be particularly useful in identifying patients with NBIAs and no iron accumulation as yet on brain imaging (for example, as in phospholipase A2, group IV (cytosolic, calcium-independent) [PLA2G6]-related disorders), and it has management implications. © 2013 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.