The Experts below are selected from a list of 138 Experts worldwide ranked by ideXlab platform

N Iwata - One of the best experts on this subject based on the ideXlab platform.

  • The pharmacological properties of CS-722, a newly synthesized centrally acting muscle relaxant
    Neuropharmacology, 1992
    Co-Authors: M. Tanabe, T. Tonohiro, T Kaneko, N Iwata
    Abstract:

    The pharmacological properties of (R)-4-chloro-2-(2-hydroxy-3-morpholinopropyl)-5-phenyl-4-isoxazolin-3-one hydrochloride (CS-722), a newly synthesized, centrally acting muscle relaxant, were studied in rats. The drug CS-722 reduced the radio frequency decerebrate rigidity in a dose-dependent manner(25-100 mg/kg, p.o.); it inhibited the increase in discharges from Ia afferent fibers, γ-motor activity, which was induced by stimulation of the reticular formation. The compound, however, showed no effect on the basal discharge of Ia afferent fibers. The Polysynaptic Reflex was depressed by CS-722 with less influence on the monosynaptic Reflex in intact and spinal preparations and CS-722 did not prolong thiopental-induced sleeping time. In rats anesthetized with halothane, CS-722 did not affect the electroencephalogram (EEG) arousal response, which was elicited by stimulation of the reticular formation. The results of this study suggest that CS-722 can exert a muscle relaxant action, at a dose range at which depression of the ascending reticular activating system was negligible. The results also suggest that depressions of the γ-motor system and the Polysynaptic Reflex may contribute to the muscle relaxant action of CS-722. © 1992.

  • Mechanisms of spinal Reflex depressant effects of CS-722, a newly synthesized centrally acting muscle relaxant, in spinal rats
    Neuropharmacology, 1992
    Co-Authors: M. Tanabe, T. Tonohiro, T Kaneko, N Iwata
    Abstract:

    The mechanisms of the depressant action of (R)-4-chloro-2-(2-hydroxy-3-morpholinopropyl)-5-phenyl-4-isoxazolin-3-one hydrochloride (CS-722), a newly synthesized centrally acting muscle relaxant, on spinal Reflexes were investigated in spinal rats. The drug CS-722 (50 solmg/kg, i.v.) depressed the Polysynaptic Reflex but was less effective on the monosynaptic Reflex. Eperisone-HCl (10 solmg/kg, i.v.) and baclofen (2 solmg/kg, i.v.) markedly decreased the monosynaptic and Polysynaptic Reflexes, with longer durations than CS-722; CS-722, eperisone and baclofen depressed the dorsal root Reflex. The excitability of the motoneurone was reduced by CS-722 and eperisone. Excitability of the primary afferent fibres was reduced by CS-722, while eperisone and baclofen had no effect. Both CS-722 and eperisone did not have a depressant influence on the focal synaptic potential. These results suggest that CS-722 and eperisone but not baclofen, have a common motoneurone-membrane-stabilizing action and that this action may contribute, in part, to the spinal Reflex depressant effects of CS-722 and eperisone. ?? 1992.

Hideki Ono - One of the best experts on this subject based on the ideXlab platform.

  • Tricyclic analogs cyclobenzaprine, amitriptyline and cyproheptadine inhibit the spinal Reflex transmission through 5-HT2 receptors
    European Journal of Pharmacology, 2003
    Co-Authors: Motoko Honda, Takashi Nishida, Hideki Ono
    Abstract:

    The centrally acting muscle relaxant cyclobenzaprine decreases the amplitude of monosynaptic Reflex potentials by inhibiting the facilitatory descending serotonergic influences in the spinal cord. Interestingly, the structure of cyclobenzaprine is much similar to those of amitriptyline and cyproheptadine. In the present study, we attempted to elucidate the relationship between 5-HT2 receptor antagonistic and inhibitory effects of cyclobenzaprine, amitriptyline, cyproheptadine and ketanserin on the spinal Reflexes. Cyclobenzaprine, amitriptyline, cyproheptadine, and ketanserin significantly inhibited facilitatory effects of 1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI) on flexor Reflexes and mono- and Polysynaptic spinal Reflex potentials in spinalized rats. In intact rats, these drugs significantly reduced the mono- and Polysynaptic Reflex potentials. 5-HT depletion significantly prevented the depression of the spinal Reflex potentials induced by these drugs. These results suggest that the inhibitory effects of cyclobenzaprine, amitriptyline, and cyproheptadine on mono- and Polysynaptic Reflex potentials are due to the inhibition of descending serotonergic systems through 5-HT2 receptors in the spinal cord. ?? 2002 Elsevier Science B.V. All rights reserved.

  • Involvement of imidazoline receptors in the centrally acting muscle-relaxant effects of tizanidine
    European Journal of Pharmacology, 2002
    Co-Authors: Motoko Honda, Yuko Sekiguchi, Naoko Sato, Hideki Ono
    Abstract:

    The centrally acting muscle relaxant tizanidine has an imidazoline structure and binds not only to ??2-adrenoceptors but also to imidazoline receptors. The role of imidazoline receptors in the muscle-relaxant effect of tizanidine was studied using the ??2-adrenoceptor/imidazoline receptor antagonist idazoxan and the ??2-adrenoceptor antagonist yohimbine. Tizanidine decreased the spinal mono- and Polysynaptic Reflexes in intact rats, and the inhibitory effects were antagonized by idazoxan but not by yohimbine. After pretreatment with prazosin, tizanidine decreased the mono- and Polysynaptic Reflexes in spinalized rats. While yohimbine partly inhibited tizanidine-induced depression of the Polysynaptic Reflex, idazoxan completely abolished tizanidine-induced depression of spinal Reflexes. Furthermore, tizanidine-induced muscle relaxation in the traction test was significantly inhibited by idazoxan but not by yohimbine. From these results, it is suggested that imidazoline receptors, but not ??2-adrenoceptors, are involved in the supraspinal inhibitory effects of tizanidine on spinal Reflexes, and at the spinal level, ??2-adrenoceptors and imidazoline receptors are involved in the inhibitory effects of tizanidine. ?? 2002 Elsevier Science B.V. All rights reserved.

  • Method for recording spinal Reflexes in mice: effects of thyrotropin-releasing hormone, DOI, tolperisone and baclofen on monosynaptic spinal Reflex potentials.
    Japanese journal of pharmacology, 2001
    Co-Authors: H. Okada, M Honda, Hideki Ono
    Abstract:

    Mice were used to record the spinal Reflex potentials and to examine the effects of some drugs upon them. In anesthetized mice, laminectomy was performed in the lumbo-sacral region, and monosynaptic Reflex potential (MSR) and Polysynaptic Reflex potential were recorded from the L5 ventral root after stimulation of the L5 dorsal root. Thyrotropin-releasing hormone (TRH) and 1-(4-iodo-2,5-dimethoxyphenyl)-2-aminopropane hydrochloride (DOI) produced transient and long-lasting increases in the MSR amplitude, respectively. Tolperisone hydrochloride and baclofen produced transient and long-lasting MSR depressions, respectively. These results show that mice can be used to record spinal Reflex potentials, and that it may be possible to study the spinal cord function of mutant and knockout mice using this method.

M. Tanabe - One of the best experts on this subject based on the ideXlab platform.

  • The pharmacological properties of CS-722, a newly synthesized centrally acting muscle relaxant
    Neuropharmacology, 1992
    Co-Authors: M. Tanabe, T. Tonohiro, T Kaneko, N Iwata
    Abstract:

    The pharmacological properties of (R)-4-chloro-2-(2-hydroxy-3-morpholinopropyl)-5-phenyl-4-isoxazolin-3-one hydrochloride (CS-722), a newly synthesized, centrally acting muscle relaxant, were studied in rats. The drug CS-722 reduced the radio frequency decerebrate rigidity in a dose-dependent manner(25-100 mg/kg, p.o.); it inhibited the increase in discharges from Ia afferent fibers, γ-motor activity, which was induced by stimulation of the reticular formation. The compound, however, showed no effect on the basal discharge of Ia afferent fibers. The Polysynaptic Reflex was depressed by CS-722 with less influence on the monosynaptic Reflex in intact and spinal preparations and CS-722 did not prolong thiopental-induced sleeping time. In rats anesthetized with halothane, CS-722 did not affect the electroencephalogram (EEG) arousal response, which was elicited by stimulation of the reticular formation. The results of this study suggest that CS-722 can exert a muscle relaxant action, at a dose range at which depression of the ascending reticular activating system was negligible. The results also suggest that depressions of the γ-motor system and the Polysynaptic Reflex may contribute to the muscle relaxant action of CS-722. © 1992.

  • Mechanisms of spinal Reflex depressant effects of CS-722, a newly synthesized centrally acting muscle relaxant, in spinal rats
    Neuropharmacology, 1992
    Co-Authors: M. Tanabe, T. Tonohiro, T Kaneko, N Iwata
    Abstract:

    The mechanisms of the depressant action of (R)-4-chloro-2-(2-hydroxy-3-morpholinopropyl)-5-phenyl-4-isoxazolin-3-one hydrochloride (CS-722), a newly synthesized centrally acting muscle relaxant, on spinal Reflexes were investigated in spinal rats. The drug CS-722 (50 solmg/kg, i.v.) depressed the Polysynaptic Reflex but was less effective on the monosynaptic Reflex. Eperisone-HCl (10 solmg/kg, i.v.) and baclofen (2 solmg/kg, i.v.) markedly decreased the monosynaptic and Polysynaptic Reflexes, with longer durations than CS-722; CS-722, eperisone and baclofen depressed the dorsal root Reflex. The excitability of the motoneurone was reduced by CS-722 and eperisone. Excitability of the primary afferent fibres was reduced by CS-722, while eperisone and baclofen had no effect. Both CS-722 and eperisone did not have a depressant influence on the focal synaptic potential. These results suggest that CS-722 and eperisone but not baclofen, have a common motoneurone-membrane-stabilizing action and that this action may contribute, in part, to the spinal Reflex depressant effects of CS-722 and eperisone. ?? 1992.

Motoko Honda - One of the best experts on this subject based on the ideXlab platform.

  • Endogenous GABA does not mediate the inhibitory effects of gabapentin on spinal Reflexes in rats.
    Journal of Pharmacological Sciences, 2020
    Co-Authors: Shinobu Shimizu, Motoko Honda, Mitsuo Tanabe
    Abstract:

    Abstract The novel antiepileptic drug gabapentin was designed as a structural analog of γ -aminobutyric acid (GABA). However, its mechanism of action remains unclear. In the present study, we investigated the effect of gabapentin on spinal Reflexes in anesthetized rats. The mono- and Polysynaptic Reflex potentials were recorded from the ipsilateral L5 ventral root after stimulation of the L5 dorsal root. The dorsal root Reflex potential, an index of presynaptic inhibition, was recorded from the ipsilateral L4 dorsal root. In non-spinalized (intact) and spinalized rats, intravenously administered gabapentin reduced the mono- and Polysynaptic Reflex potentials in a dose-dependent manner. These inhibitory effects of gabapentin were not suppressed by the GABA A antagonist picrotoxin. Moreover, gabapentin also decreased spinal Reflexes in spinalized rats depleted of spinal GABA with semicarbazide, an inhibitor of the GABA-synthesizing enzyme. The dorsal root Reflex potentials were not affected by gabapentin. These results suggest that endogenous GABA does not mediate the inhibitory effects of gabapentin on spinal Reflexes.

  • Tricyclic analogs cyclobenzaprine, amitriptyline and cyproheptadine inhibit the spinal Reflex transmission through 5-HT2 receptors
    European Journal of Pharmacology, 2020
    Co-Authors: Motoko Honda, Takashi Nishida
    Abstract:

    Abstract The centrally acting muscle relaxant cyclobenzaprine decreases the amplitude of monosynaptic Reflex potentials by inhibiting the facilitatory descending serotonergic influences in the spinal cord. Interestingly, the structure of cyclobenzaprine is much similar to those of amitriptyline and cyproheptadine. In the present study, we attempted to elucidate the relationship between 5-HT2 receptor antagonistic and inhibitory effects of cyclobenzaprine, amitriptyline, cyproheptadine and ketanserin on the spinal Reflexes. Cyclobenzaprine, amitriptyline, cyproheptadine, and ketanserin significantly inhibited facilitatory effects of 1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI) on flexor Reflexes and mono- and Polysynaptic spinal Reflex potentials in spinalized rats. In intact rats, these drugs significantly reduced the mono- and Polysynaptic Reflex potentials. 5-HT depletion significantly prevented the depression of the spinal Reflex potentials induced by these drugs. These results suggest that the inhibitory effects of cyclobenzaprine, amitriptyline, and cyproheptadine on mono- and Polysynaptic Reflex potentials are due to the inhibition of descending serotonergic systems through 5-HT2 receptors in the spinal cord.

  • Tricyclic analogs cyclobenzaprine, amitriptyline and cyproheptadine inhibit the spinal Reflex transmission through 5-HT(2) receptors.
    European journal of pharmacology, 2003
    Co-Authors: Motoko Honda, Takashi Nishida
    Abstract:

    The centrally acting muscle relaxant cyclobenzaprine decreases the amplitude of monosynaptic Reflex potentials by inhibiting the facilitatory descending serotonergic influences in the spinal cord. Interestingly, the structure of cyclobenzaprine is much similar to those of amitriptyline and cyproheptadine. In the present study, we attempted to elucidate the relationship between 5-HT(2) receptor antagonistic and inhibitory effects of cyclobenzaprine, amitriptyline, cyproheptadine and ketanserin on the spinal Reflexes. Cyclobenzaprine, amitriptyline, cyproheptadine, and ketanserin significantly inhibited facilitatory effects of 1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI) on flexor Reflexes and mono- and Polysynaptic spinal Reflex potentials in spinalized rats. In intact rats, these drugs significantly reduced the mono- and Polysynaptic Reflex potentials. 5-HT depletion significantly prevented the depression of the spinal Reflex potentials induced by these drugs. These results suggest that the inhibitory effects of cyclobenzaprine, amitriptyline, and cyproheptadine on mono- and Polysynaptic Reflex potentials are due to the inhibition of descending serotonergic systems through 5-HT(2) receptors in the spinal cord.

  • Tricyclic analogs cyclobenzaprine, amitriptyline and cyproheptadine inhibit the spinal Reflex transmission through 5-HT2 receptors
    European Journal of Pharmacology, 2003
    Co-Authors: Motoko Honda, Takashi Nishida, Hideki Ono
    Abstract:

    The centrally acting muscle relaxant cyclobenzaprine decreases the amplitude of monosynaptic Reflex potentials by inhibiting the facilitatory descending serotonergic influences in the spinal cord. Interestingly, the structure of cyclobenzaprine is much similar to those of amitriptyline and cyproheptadine. In the present study, we attempted to elucidate the relationship between 5-HT2 receptor antagonistic and inhibitory effects of cyclobenzaprine, amitriptyline, cyproheptadine and ketanserin on the spinal Reflexes. Cyclobenzaprine, amitriptyline, cyproheptadine, and ketanserin significantly inhibited facilitatory effects of 1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI) on flexor Reflexes and mono- and Polysynaptic spinal Reflex potentials in spinalized rats. In intact rats, these drugs significantly reduced the mono- and Polysynaptic Reflex potentials. 5-HT depletion significantly prevented the depression of the spinal Reflex potentials induced by these drugs. These results suggest that the inhibitory effects of cyclobenzaprine, amitriptyline, and cyproheptadine on mono- and Polysynaptic Reflex potentials are due to the inhibition of descending serotonergic systems through 5-HT2 receptors in the spinal cord. ?? 2002 Elsevier Science B.V. All rights reserved.

  • Involvement of imidazoline receptors in the centrally acting muscle-relaxant effects of tizanidine
    European Journal of Pharmacology, 2002
    Co-Authors: Motoko Honda, Yuko Sekiguchi, Naoko Sato, Hideki Ono
    Abstract:

    The centrally acting muscle relaxant tizanidine has an imidazoline structure and binds not only to ??2-adrenoceptors but also to imidazoline receptors. The role of imidazoline receptors in the muscle-relaxant effect of tizanidine was studied using the ??2-adrenoceptor/imidazoline receptor antagonist idazoxan and the ??2-adrenoceptor antagonist yohimbine. Tizanidine decreased the spinal mono- and Polysynaptic Reflexes in intact rats, and the inhibitory effects were antagonized by idazoxan but not by yohimbine. After pretreatment with prazosin, tizanidine decreased the mono- and Polysynaptic Reflexes in spinalized rats. While yohimbine partly inhibited tizanidine-induced depression of the Polysynaptic Reflex, idazoxan completely abolished tizanidine-induced depression of spinal Reflexes. Furthermore, tizanidine-induced muscle relaxation in the traction test was significantly inhibited by idazoxan but not by yohimbine. From these results, it is suggested that imidazoline receptors, but not ??2-adrenoceptors, are involved in the supraspinal inhibitory effects of tizanidine on spinal Reflexes, and at the spinal level, ??2-adrenoceptors and imidazoline receptors are involved in the inhibitory effects of tizanidine. ?? 2002 Elsevier Science B.V. All rights reserved.

T. Tonohiro - One of the best experts on this subject based on the ideXlab platform.

  • The pharmacological properties of CS-722, a newly synthesized centrally acting muscle relaxant
    Neuropharmacology, 1992
    Co-Authors: M. Tanabe, T. Tonohiro, T Kaneko, N Iwata
    Abstract:

    The pharmacological properties of (R)-4-chloro-2-(2-hydroxy-3-morpholinopropyl)-5-phenyl-4-isoxazolin-3-one hydrochloride (CS-722), a newly synthesized, centrally acting muscle relaxant, were studied in rats. The drug CS-722 reduced the radio frequency decerebrate rigidity in a dose-dependent manner(25-100 mg/kg, p.o.); it inhibited the increase in discharges from Ia afferent fibers, γ-motor activity, which was induced by stimulation of the reticular formation. The compound, however, showed no effect on the basal discharge of Ia afferent fibers. The Polysynaptic Reflex was depressed by CS-722 with less influence on the monosynaptic Reflex in intact and spinal preparations and CS-722 did not prolong thiopental-induced sleeping time. In rats anesthetized with halothane, CS-722 did not affect the electroencephalogram (EEG) arousal response, which was elicited by stimulation of the reticular formation. The results of this study suggest that CS-722 can exert a muscle relaxant action, at a dose range at which depression of the ascending reticular activating system was negligible. The results also suggest that depressions of the γ-motor system and the Polysynaptic Reflex may contribute to the muscle relaxant action of CS-722. © 1992.

  • Mechanisms of spinal Reflex depressant effects of CS-722, a newly synthesized centrally acting muscle relaxant, in spinal rats
    Neuropharmacology, 1992
    Co-Authors: M. Tanabe, T. Tonohiro, T Kaneko, N Iwata
    Abstract:

    The mechanisms of the depressant action of (R)-4-chloro-2-(2-hydroxy-3-morpholinopropyl)-5-phenyl-4-isoxazolin-3-one hydrochloride (CS-722), a newly synthesized centrally acting muscle relaxant, on spinal Reflexes were investigated in spinal rats. The drug CS-722 (50 solmg/kg, i.v.) depressed the Polysynaptic Reflex but was less effective on the monosynaptic Reflex. Eperisone-HCl (10 solmg/kg, i.v.) and baclofen (2 solmg/kg, i.v.) markedly decreased the monosynaptic and Polysynaptic Reflexes, with longer durations than CS-722; CS-722, eperisone and baclofen depressed the dorsal root Reflex. The excitability of the motoneurone was reduced by CS-722 and eperisone. Excitability of the primary afferent fibres was reduced by CS-722, while eperisone and baclofen had no effect. Both CS-722 and eperisone did not have a depressant influence on the focal synaptic potential. These results suggest that CS-722 and eperisone but not baclofen, have a common motoneurone-membrane-stabilizing action and that this action may contribute, in part, to the spinal Reflex depressant effects of CS-722 and eperisone. ?? 1992.