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Thies Peters - One of the best experts on this subject based on the ideXlab platform.
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kavain inhibits veratridine activated voltage dependent na channels in synaptosomes prepared from rat cerebral cortex
Neuropharmacology, 1995Co-Authors: Johannes Gleitz, A. Beile, Thies PetersAbstract:Abstract Kava pyrones are pharmacologically active compounds extracted from Piper methysticum Forst. Because kava pyrones were characterized by their anticonvulsive, analgesic and centrally muscle relaxing action, we investigated the influence of (±)-kavain, a synthetic kava pyrone, on veratridine-stimulated increase in intrasynaptosomal Na + concentration ([Na + ] i ) of rat cerebrocortical synaptosomes. [Na + ] i was measured spectrofluorometrically employing SBFI as Na + sensitive fluorescence dye. Veratridine (5 μmol/l) enhanced basal [Na + ] i 6.6-fold from 11.3 to 74.1mmol/l Na + . Incubation of synaptosomes for 100 sec with (±)-kavain was sufficient to reduce dose dependently the stimulated increase of [Na + ] i with an IC 50 value of 86.0 μmol/l, and almost complete inhibition of Na + -channels was attained with 400 μmol/l (±)-kavain. The reference compounds, procain (400 μmol/l) and tetrodotoxin (TTX, 10 μmol/l) reduced veratridine-elevated [Na + ] i to 30.4% and 7.9% of control whereas the centrally acting muscle relaxant Mephenesin (400 μmol/l) was without any effect. Postapplication of 400 μmol/l (±)-kavain or 10 μmol/l TTX immediately diminished veratridine-elevated [Na + ] i to nearly basal levels with a half life time of 69.7 and 41.8 sec, respectively. To study the influence of (±)-kavain on non stimulated synaptosomes, an increase in [Na + ] i was induced by 200 μmol/l ouabain, which enhanced [Na + ] i hyperbolically with an initial rate of 18.4 mmol Na + /l min. Preincubation of synaptosomes with 400 μmol/l (±)-kavain or 10 μmol/l TTX partly prevented Na + -influx for both compounds to the same extent of about 57% of control. The presented data indicate a fast and specific inhibition of voltage-dependent Na + -channels by (±)-kavain.
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kavain inhibits veratridine activated voltage dependent na channels in synaptosomes prepared from rat cerebral cortex
Neuropharmacology, 1995Co-Authors: Johannes Gleitz, A. Beile, Thies PetersAbstract:Kava pyrones are pharmacologically active compounds extracted from Piper methysticum Forst. Because kava pyrones were characterized by their anticonvulsive, analgesic and centrally muscle relaxing action, we investigated the influence of (+/-)-kavain, a synthetic kava pyrone, on veratridine-stimulated increase in intrasynaptosomal Na+ concentration ([Na+]i) of rat cerebrocortical synaptosomes. [Na+]i was measured spectrofluorometrically employing SBFI as Na+ sensitive fluorescence dye. Veratridine (5 mumol/I) enhanced basal [Na+]i 6.6-fold from 11.3 to 74.1 mmol/l Na+. Incubation of synaptosomes for 100 sec with (+/-)-kavain was sufficient to reduce dose dependently the stimulated increase of [Na+]i with an IC50 value of 86.0 mumol/l, and almost complete inhibition of Na(+)-channels was attained with 400 mumol/l) reduced veratridine-elevated [Na+]i to 30.4% and 7.9% of control whereas the centrally acting muscle relaxant Mephenesin (400 mumol/l) was without any effect. Postapplication of 400 mumol/l (+/-)-kavain or 10 mumol/l TTX immediately diminished veratridine-elevated [Na+]i to nearly basal levels with a half life time of 69.7 and 41.8 sec, respectively. To study the influence of (+/-)-kavain on non stimulated synaptosomes, an increase in [Na+]i was induced by 200 mumol/l ouabain, which enhanced [Na+]i hyperbolically with an initial rate of 18.4 mmol Na+/l min. Preincubation of synaptosomes with 400 mumol/l (+/-)-kavain or 10 mumol/l TTX partly prevented Na(+)-influx for both compounds to the same extent of about 57% of control. The presented data indicate a fast and specific inhibition of voltage-dependent Na(+)-channels by (+/-)-kavain.
Johannes Gleitz - One of the best experts on this subject based on the ideXlab platform.
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kavain inhibits veratridine activated voltage dependent na channels in synaptosomes prepared from rat cerebral cortex
Neuropharmacology, 1995Co-Authors: Johannes Gleitz, A. Beile, Thies PetersAbstract:Abstract Kava pyrones are pharmacologically active compounds extracted from Piper methysticum Forst. Because kava pyrones were characterized by their anticonvulsive, analgesic and centrally muscle relaxing action, we investigated the influence of (±)-kavain, a synthetic kava pyrone, on veratridine-stimulated increase in intrasynaptosomal Na + concentration ([Na + ] i ) of rat cerebrocortical synaptosomes. [Na + ] i was measured spectrofluorometrically employing SBFI as Na + sensitive fluorescence dye. Veratridine (5 μmol/l) enhanced basal [Na + ] i 6.6-fold from 11.3 to 74.1mmol/l Na + . Incubation of synaptosomes for 100 sec with (±)-kavain was sufficient to reduce dose dependently the stimulated increase of [Na + ] i with an IC 50 value of 86.0 μmol/l, and almost complete inhibition of Na + -channels was attained with 400 μmol/l (±)-kavain. The reference compounds, procain (400 μmol/l) and tetrodotoxin (TTX, 10 μmol/l) reduced veratridine-elevated [Na + ] i to 30.4% and 7.9% of control whereas the centrally acting muscle relaxant Mephenesin (400 μmol/l) was without any effect. Postapplication of 400 μmol/l (±)-kavain or 10 μmol/l TTX immediately diminished veratridine-elevated [Na + ] i to nearly basal levels with a half life time of 69.7 and 41.8 sec, respectively. To study the influence of (±)-kavain on non stimulated synaptosomes, an increase in [Na + ] i was induced by 200 μmol/l ouabain, which enhanced [Na + ] i hyperbolically with an initial rate of 18.4 mmol Na + /l min. Preincubation of synaptosomes with 400 μmol/l (±)-kavain or 10 μmol/l TTX partly prevented Na + -influx for both compounds to the same extent of about 57% of control. The presented data indicate a fast and specific inhibition of voltage-dependent Na + -channels by (±)-kavain.
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kavain inhibits veratridine activated voltage dependent na channels in synaptosomes prepared from rat cerebral cortex
Neuropharmacology, 1995Co-Authors: Johannes Gleitz, A. Beile, Thies PetersAbstract:Kava pyrones are pharmacologically active compounds extracted from Piper methysticum Forst. Because kava pyrones were characterized by their anticonvulsive, analgesic and centrally muscle relaxing action, we investigated the influence of (+/-)-kavain, a synthetic kava pyrone, on veratridine-stimulated increase in intrasynaptosomal Na+ concentration ([Na+]i) of rat cerebrocortical synaptosomes. [Na+]i was measured spectrofluorometrically employing SBFI as Na+ sensitive fluorescence dye. Veratridine (5 mumol/I) enhanced basal [Na+]i 6.6-fold from 11.3 to 74.1 mmol/l Na+. Incubation of synaptosomes for 100 sec with (+/-)-kavain was sufficient to reduce dose dependently the stimulated increase of [Na+]i with an IC50 value of 86.0 mumol/l, and almost complete inhibition of Na(+)-channels was attained with 400 mumol/l) reduced veratridine-elevated [Na+]i to 30.4% and 7.9% of control whereas the centrally acting muscle relaxant Mephenesin (400 mumol/l) was without any effect. Postapplication of 400 mumol/l (+/-)-kavain or 10 mumol/l TTX immediately diminished veratridine-elevated [Na+]i to nearly basal levels with a half life time of 69.7 and 41.8 sec, respectively. To study the influence of (+/-)-kavain on non stimulated synaptosomes, an increase in [Na+]i was induced by 200 mumol/l ouabain, which enhanced [Na+]i hyperbolically with an initial rate of 18.4 mmol Na+/l min. Preincubation of synaptosomes with 400 mumol/l (+/-)-kavain or 10 mumol/l TTX partly prevented Na(+)-influx for both compounds to the same extent of about 57% of control. The presented data indicate a fast and specific inhibition of voltage-dependent Na(+)-channels by (+/-)-kavain.
Emilio J Cocinero - One of the best experts on this subject based on the ideXlab platform.
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conformational flexibility of Mephenesin
Journal of Physical Chemistry B, 2014Co-Authors: Patricia Ecija, Luca Evangelisti, Montserrat Vallejo, Francisco J Basterretxea, Alberto Lesarri, Fernando Castano, Walther Caminati, Emilio J CocineroAbstract:The Mephenesin molecule (3-(2-methylphenoxy)propane-1,2-diol) serves as a test bank to explore several structural and dynamical issues, such as conformational flexibility, the orientation of the carbon linear chain relative to the benzene plane, or the effect of substituent position on the rotational barrier of a methyl group. The molecule has been studied by rotational spectroscopy in the 4–18 GHz frequency range by Fourier-transform methods in a supersonic expansion. The experiment has been backed by a previous conformational search plus optimization of the lowest energy structures by ab initio and density functional quantum calculations. The three lowest-lying conformers that can interconvert to each other by simple bond rotations have been detected in the jet. Rotational parameters for all structures have been obtained, and methyl torsional barriers have been determined for the two lowest-lying rotamers. The lowest-lying structure of Mephenesin is highly planar, with all carbon atoms lying nearly in t...
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Conformational Flexibility of Mephenesin
2014Co-Authors: Patricia Écija, Luca Evangelisti, Montserrat Vallejo, Francisco J Basterretxea, Alberto Lesarri, Walther Caminati, Fernando Castaño, Emilio J CocineroAbstract:The Mephenesin molecule (3-(2-methylphenoxy)propane-1,2-diol) serves as a test bank to explore several structural and dynamical issues, such as conformational flexibility, the orientation of the carbon linear chain relative to the benzene plane, or the effect of substituent position on the rotational barrier of a methyl group. The molecule has been studied by rotational spectroscopy in the 4–18 GHz frequency range by Fourier-transform methods in a supersonic expansion. The experiment has been backed by a previous conformational search plus optimization of the lowest energy structures by ab initio and density functional quantum calculations. The three lowest-lying conformers that can interconvert to each other by simple bond rotations have been detected in the jet. Rotational parameters for all structures have been obtained, and methyl torsional barriers have been determined for the two lowest-lying rotamers. The lowest-lying structure of Mephenesin is highly planar, with all carbon atoms lying nearly in the benzene ring plane, and is stabilized by the formation of cooperative intramolecular hydrogen bonding. An estimation of the relative abundance of the detected conformers indicates that the energetically most stable conformer will have an abundance near 80% at temperatures relevant for biological activity
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conformational flexibility of Mephenesin b
The Journal of Physical Chemistry, 2014Co-Authors: Patricia Ecija, Luca Evangelisti, Montserrat Vallejo, Francisco J Basterretxea, Alberto Lesarri, Fernando Castano, Walther Caminati, Emilio J CocineroAbstract:The Mephenesin molecule (3-(2-methylphenoxy)propane-1,2-diol) serves as a test bank to explore several structural and dynamical issues, such as conformational flexibility, the orientation of the carbon linear chain relative to the benzene plane, or the effect of substituent position on the rotational barrier of a methyl group. The molecule has been studied by rotational spectroscopy in the 4–18 GHz frequency range by Fourier-transform methods in a supersonic expansion. The experiment has been backed by a previous conformational search plus optimization of the lowest energy structures by ab initio and density functional quantum calculations. The three lowest-lying conformers that can interconvert to each other by simple bond rotations have been detected in the jet. Rotational parameters for all structures have been obtained, and methyl torsional barriers have been determined for the two lowest-lying rotamers. The lowest-lying structure of Mephenesin is highly planar, with all carbon atoms lying nearly in the benzene ring plane, and is stabilized by the formation of cooperative intramolecular hydrogen bonding. An estimation of the relative abundance of the detected conformers indicates that the energetically most stable conformer will have an abundance near 80% at temperatures relevant for biological activity.
A. Beile - One of the best experts on this subject based on the ideXlab platform.
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kavain inhibits veratridine activated voltage dependent na channels in synaptosomes prepared from rat cerebral cortex
Neuropharmacology, 1995Co-Authors: Johannes Gleitz, A. Beile, Thies PetersAbstract:Abstract Kava pyrones are pharmacologically active compounds extracted from Piper methysticum Forst. Because kava pyrones were characterized by their anticonvulsive, analgesic and centrally muscle relaxing action, we investigated the influence of (±)-kavain, a synthetic kava pyrone, on veratridine-stimulated increase in intrasynaptosomal Na + concentration ([Na + ] i ) of rat cerebrocortical synaptosomes. [Na + ] i was measured spectrofluorometrically employing SBFI as Na + sensitive fluorescence dye. Veratridine (5 μmol/l) enhanced basal [Na + ] i 6.6-fold from 11.3 to 74.1mmol/l Na + . Incubation of synaptosomes for 100 sec with (±)-kavain was sufficient to reduce dose dependently the stimulated increase of [Na + ] i with an IC 50 value of 86.0 μmol/l, and almost complete inhibition of Na + -channels was attained with 400 μmol/l (±)-kavain. The reference compounds, procain (400 μmol/l) and tetrodotoxin (TTX, 10 μmol/l) reduced veratridine-elevated [Na + ] i to 30.4% and 7.9% of control whereas the centrally acting muscle relaxant Mephenesin (400 μmol/l) was without any effect. Postapplication of 400 μmol/l (±)-kavain or 10 μmol/l TTX immediately diminished veratridine-elevated [Na + ] i to nearly basal levels with a half life time of 69.7 and 41.8 sec, respectively. To study the influence of (±)-kavain on non stimulated synaptosomes, an increase in [Na + ] i was induced by 200 μmol/l ouabain, which enhanced [Na + ] i hyperbolically with an initial rate of 18.4 mmol Na + /l min. Preincubation of synaptosomes with 400 μmol/l (±)-kavain or 10 μmol/l TTX partly prevented Na + -influx for both compounds to the same extent of about 57% of control. The presented data indicate a fast and specific inhibition of voltage-dependent Na + -channels by (±)-kavain.
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kavain inhibits veratridine activated voltage dependent na channels in synaptosomes prepared from rat cerebral cortex
Neuropharmacology, 1995Co-Authors: Johannes Gleitz, A. Beile, Thies PetersAbstract:Kava pyrones are pharmacologically active compounds extracted from Piper methysticum Forst. Because kava pyrones were characterized by their anticonvulsive, analgesic and centrally muscle relaxing action, we investigated the influence of (+/-)-kavain, a synthetic kava pyrone, on veratridine-stimulated increase in intrasynaptosomal Na+ concentration ([Na+]i) of rat cerebrocortical synaptosomes. [Na+]i was measured spectrofluorometrically employing SBFI as Na+ sensitive fluorescence dye. Veratridine (5 mumol/I) enhanced basal [Na+]i 6.6-fold from 11.3 to 74.1 mmol/l Na+. Incubation of synaptosomes for 100 sec with (+/-)-kavain was sufficient to reduce dose dependently the stimulated increase of [Na+]i with an IC50 value of 86.0 mumol/l, and almost complete inhibition of Na(+)-channels was attained with 400 mumol/l) reduced veratridine-elevated [Na+]i to 30.4% and 7.9% of control whereas the centrally acting muscle relaxant Mephenesin (400 mumol/l) was without any effect. Postapplication of 400 mumol/l (+/-)-kavain or 10 mumol/l TTX immediately diminished veratridine-elevated [Na+]i to nearly basal levels with a half life time of 69.7 and 41.8 sec, respectively. To study the influence of (+/-)-kavain on non stimulated synaptosomes, an increase in [Na+]i was induced by 200 mumol/l ouabain, which enhanced [Na+]i hyperbolically with an initial rate of 18.4 mmol Na+/l min. Preincubation of synaptosomes with 400 mumol/l (+/-)-kavain or 10 mumol/l TTX partly prevented Na(+)-influx for both compounds to the same extent of about 57% of control. The presented data indicate a fast and specific inhibition of voltage-dependent Na(+)-channels by (+/-)-kavain.
Hans Schick - One of the best experts on this subject based on the ideXlab platform.
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kinetic resolution of rac 3 2 methylphenoxy propane 1 2 diol Mephenesin by sequential lipase catalyzed transesterification
Tetrahedron-asymmetry, 1991Co-Authors: Fritz Theil, Sibylle Ballschuh, A Kunath, Hans SchickAbstract:Abstract The kinetic resolution of rac-3-(2-methylphenoxy)propane-1,2-diol ( rac-1 , Mephenesin) by sequential lipase-catalyzed transesterification with vinyl acetate in tetrahydrofuran/triethylamine in the presence of lipase Amano PS is described.