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1.
Artículo en Ruso | MEDLINE | ID: mdl-22693734

RESUMEN

The objective of the present clinical and psychopathological study was to estimate the influence of high-intensity white and yellow phototherapy on the clinical condition of 41 and 18 patients respectively presenting with astheno-depressive syndrome. The control group was comprised of 42 patients who were treated by standard pharmacotherapy. Clinical observations of the patients were supplemented by the evaluation of their conditions and characteristics using the Symptom Checklist-90 questionnaire, the Bekhterev Depression Inventory, and the Beck Depression Inventory. The patients of the three groups were surveyed before and within 20 days after the initiation of the treatment. It was shown that white light phototherapy considerably reduced the severity of asthenia and depression. Yellow light phototherapy proved more efficacious in the patients with asthenia and somatovegetative dysfunctions.


Asunto(s)
Astenia/terapia , Cromoterapia/métodos , Depresión/terapia , Trastornos Neuróticos/terapia , Adolescente , Adulto , Anciano , Astenia/psicología , Depresión/psicología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Trastornos Neuróticos/psicología
2.
Br J Pharmacol ; 155(3): 424-33, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18604239

RESUMEN

BACKGROUND AND PURPOSE: Heterologous expression of alpha1, beta2 and gamma2S(gamma1) subunits produces a mixed population of GABA(A) receptors containing alpha1beta2 or alpha1beta2gamma2S(gamma1) subunits. GABA sensitivity (lower in receptors containing gamma1 or gamma2S subunits) and the potentiation of GABA-activated chloride currents (I(GABA)) by benzodiazepines (BZDs) are dependent on gamma2S(gamma1) incorporation. A variable gamma subunit incorporation may affect the estimation of I(GABA) potentiation by BZDs. We propose an approach for estimation of BZD efficiency that accounts for mixed population of alpha1beta2 and alpha1beta2gamma2S(gamma1) receptors. EXPERIMENTAL APPROACH: We investigated the relation between GABA sensitivity (EC50) and BZD modulation by analysing triazolam-, clotiazepam- and midazolam-induced potentiation of I(GABA) in Xenopus oocytes under two-microelectrode voltage clamp. KEY RESULTS: Plotting EC50 versus BZD-induced shifts of GABA concentration-response curves (DeltaEC50(BZD)) of oocytes injected with different amounts of alpha1, beta2 and gamma2S(gamma1) cRNA (1:1:1-1:1:10) revealed a linear regression between gamma2S(gamma1)-mediated reduction of GABA sensitivity (EC50) and DeltaEC50(BZD). The slope factors of the regression were always higher for oocytes expressing alpha1beta2gamma1 subunit receptors (1.8 +/- 0.1 (triazolam), 1.6 +/- 0.1 (clotiazepam), 2.3 +/- 0.2 (midazolam)) than for oocytes expressing alpha1beta2gamma2S receptors (1.4 +/- 0.1 (triazolam), 1.4 +/- 0.1 (clotiazepam), 1.3 +/- 0.1 (midazolam)). Mutant GABA(A) receptors (alpha1beta2-R207Cgamma2S) with lower GABA sensitivity showed higher drug efficiencies (slope factors=1.1 +/- 0.1 (triazolam), 1.1 +/- 0.1 (clotiazepam), 1.2 +/- 0.1 (midazolam)). CONCLUSIONS AND IMPLICATIONS: Regression analysis enabled the estimation of BZD efficiency when variable mixtures of alpha1beta2 and alpha1beta2gamma2S(gamma1) receptors are expressed and provided new insights into the gamma2S(gamma1) dependency of BZD action.


Asunto(s)
Benzodiazepinas/farmacología , Moduladores del GABA/farmacología , Receptores de GABA-A/efectos de los fármacos , Animales , Azepinas/administración & dosificación , Azepinas/farmacología , Benzodiazepinas/administración & dosificación , Relación Dosis-Respuesta a Droga , Femenino , Moduladores del GABA/administración & dosificación , Midazolam/administración & dosificación , Midazolam/farmacología , Oocitos , Técnicas de Placa-Clamp , Subunidades de Proteína , Receptores de GABA-A/metabolismo , Análisis de Regresión , Triazolam/administración & dosificación , Triazolam/farmacología , Xenopus laevis
3.
J Phys Chem B ; 112(31): 9437-43, 2008 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-18624423

RESUMEN

Twenty-one zeolitic imidazolate metal-organic frameworks based on Zn connectors (ZIFs) are derived and compared to known imidazolate networks. Not-yet-synthesized zinc imidazolates are identified on the basis of DFT total energy scoring. The structure with lowest energy is not porous and represents an unusual structure type with zni topology. Total energy scoring indicates the lcs and pcb networks as reliable ZIF candidates. The intrinsic channel chirality of the lcs network makes this rare topology an attractive target for the synthetic effort. Among the porous ZIFs candidates, the sodalite type, sod, is also found.

4.
Neuropharmacology ; 53(1): 178-87, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17585957

RESUMEN

Valerian is a commonly used herbal medicinal product for the treatment of anxiety and insomnia. Here we report the stimulation of chloride currents through GABA(A) receptors (I(GABA)) by valerenic acid (VA), a constituent of Valerian. To analyse the molecular basis of VA action, we expressed GABA(A) receptors with 13 different subunit compositions in Xenopus oocytes and measured I(GABA) using the two-microelectrode voltage-clamp technique. We report a subtype-dependent stimulation of I(GABA) by VA. Only channels incorporating beta(2) or beta(3) subunits were stimulated by VA. Replacing beta(2/3) by beta(1) drastically reduced the sensitivity of the resulting GABA(A) channels. The stimulatory effect of VA on alpha(1)beta(2) receptors was substantially reduced by the point mutation beta(2N265S) (known to inhibit loreclezole action). Mutating the corresponding residue of beta(1) (beta(1S290N)) induced VA sensitivity in alpha(1)beta(1S290N) comparable to alpha(1)beta(2) receptors. Modulation of I(GABA) was not significantly dependent on incorporation of alpha(1), alpha(2), alpha(3) or alpha(5) subunits. VA displayed a significantly lower efficiency on channels incorporating alpha(4) subunits. I(GABA) modulation by VA was not gamma subunit dependent and not inhibited by flumazenil (1 microM). VA shifted the GABA concentration-effect curve towards lower GABA concentrations and elicited substantial currents through GABA(A) channels at > or = 30 microM. At higher concentrations (> or = 100 microM), VA and acetoxy-VA inhibit I(GABA). A possible open channel block mechanism is discussed. In summary, VA was identified as a subunit specific allosteric modulator of GABA(A) receptors that is likely to interact with the loreclezole binding pocket.


Asunto(s)
Canales de Cloruro/efectos de los fármacos , Indenos/farmacología , Receptores de GABA-A/fisiología , Sesquiterpenos/farmacología , Animales , Canales de Cloruro/fisiología , Relación Dosis-Respuesta a Droga , Relación Dosis-Respuesta en la Radiación , Interacciones Farmacológicas , Estimulación Eléctrica/métodos , Flumazenil/farmacología , Agonistas del GABA/farmacología , Antagonistas del GABA/farmacología , Moduladores del GABA/farmacología , Potenciales de la Membrana/efectos de los fármacos , Potenciales de la Membrana/fisiología , Potenciales de la Membrana/efectos de la radiación , Mutación/fisiología , Oocitos , Técnicas de Placa-Clamp/métodos , Subunidades de Proteína/genética , Subunidades de Proteína/fisiología , Receptores de GABA-A/genética , Xenopus laevis , Ácido gamma-Aminobutírico/farmacología
5.
Br J Pharmacol ; 174(18): 3081-3093, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28681507

RESUMEN

BACKGROUND AND PURPOSE: Human ether-a-go-go-related gene (hERG; Kv 11.1) channel inhibition is a widely accepted predictor of cardiac arrhythmia. hERG channel inhibition alone is often insufficient to predict pro-arrhythmic drug effects. This study used a library of dofetilide derivatives to investigate the relationship between standard measures of hERG current block in an expression system and changes in action potential duration (APD) in human-induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs). The interference from accompanying block of Cav 1.2 and Nav 1.5 channels was investigated along with an in silico AP model. EXPERIMENTAL APPROACH: Drug-induced changes in APD were assessed in hiPSC-CMs using voltage-sensitive dyes. The IC50 values for dofetilide and 13 derivatives on hERG current were estimated in an HEK293 expression system. The relative potency of each drug on APD was estimated by calculating the dose (D150 ) required to prolong the APD at 90% (APD90 ) repolarization by 50%. KEY RESULTS: The D150 in hiPSC-CMs was linearly correlated with IC50 of hERG current. In silico simulations supported this finding. Three derivatives inhibited hERG without prolonging APD, and these compounds also inhibited Cav 1.2 and/or Nav 1.5 in a channel state-dependent manner. Adding Cav 1.2 and Nav 1.2 block to the in silico model recapitulated the direction but not the extent of the APD change. CONCLUSIONS AND IMPLICATIONS: Potency of hERG current inhibition correlates linearly with an index of APD in hiPSC-CMs. The compounds that do not correlate have additional effects including concomitant block of Cav 1.2 and/or Nav 1.5 channels. In silico simulations of hiPSC-CMs APs confirm the principle of the multiple ion channel effects.


Asunto(s)
Potenciales de Acción/efectos de los fármacos , Canales de Potasio Éter-A-Go-Go/antagonistas & inhibidores , Síndrome de QT Prolongado/inducido químicamente , Fenetilaminas/farmacología , Sulfonamidas/farmacología , Células Cultivadas , Relación Dosis-Respuesta a Droga , Canales de Potasio Éter-A-Go-Go/genética , Canales de Potasio Éter-A-Go-Go/metabolismo , Células HEK293 , Humanos , Fenetilaminas/química , Relación Estructura-Actividad , Sulfonamidas/química
6.
Zh Nevrol Psikhiatr Im S S Korsakova ; 111(10 Pt 1): 51-3, 2011.
Artículo en Ruso | MEDLINE | ID: mdl-22500314

RESUMEN

Fifty-five patients with neurotic and neurosis-like disorders and 20 healthy controls, aged 17-64 years, have been examined. The basic research method was electroencephalography (EEG) with the fractal analysis of alpha power fluctuations. In patients, the changes in the fractal structure were of the same direction: the decrease of fractal indexes of low-frequency fluctuations and the increase of fractal indexes of mid-frequency fluctuations. Patients with neurosis-like disorders, in comparison to those with neurotic disorders, were characterized by more expressed (quantitative) changes in fractal structures of more extended character. It suggests the presence of deeper pathological changes in patients with neurosis-like disorders.


Asunto(s)
Ritmo alfa , Trastornos Neuróticos/diagnóstico , Trastornos Neuróticos/fisiopatología , Adolescente , Adulto , Femenino , Fractales , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
7.
Biochem Pharmacol ; 77(8): 1437-44, 2009 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-19426683

RESUMEN

Nematode infections cause human morbidity and enormous economic loss in livestock. Since resistance against currently available anthelmintics is a worldwide problem, there is a continuous need for new compounds. The cyclooctadepsipeptide PF1022A is a novel anthelmintic that binds to the latrophilin-like transmembrane receptor important for pharyngeal pumping in nematodes. Furthermore, PF1022A binds to GABA receptors, which might contribute to the anthelmintic effect. Like other cyclodepsipeptides, PF1022A acts as an ionophore. However, no correlation between ionophoric activity and anthelmintic properties was found. This is the first study describing the effect of PF1022A on mammalian cells and tissues. While channel-forming activity was observed already at very low concentrations, changes in intracellular ion concentrations and reduction of contractility in isolated guinea pig ileum occurred at multiples of anthelmintically active concentrations. PF1022A did not induce necrotic cell death indicated by complete lack of cellular lactate dehydrogenase release. In contrast, apoptosis induction via the mitochondrial pathway was suggested for long-term drug treatment at high concentrations due to numerous apoptotic morphological changes as well as mitochondrial membrane depolarisation. Short time effects were based on cell cycle blockade in G(0)/G(1) phase. Additionally, the cell cycle and apoptosis regulating proteins p53, p21 and bax, but not Bcl-2 were shown to impact on PF1022A-induced cytotoxicity. However, since PF1022A-induced cytotoxicity was found at drug concentrations higher than those used in anthelmintic treatment, it can be suggested that PF1022A intake might not impair human or animal health. Thus, PF1022A seems to be a safe alternative to other anthelmintic drugs.


Asunto(s)
Antinematodos/efectos adversos , Depsipéptidos/efectos adversos , Íleon/efectos de los fármacos , Animales , Antinematodos/metabolismo , Calcio/metabolismo , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Depsipéptidos/metabolismo , Cobayas , Humanos , Íleon/fisiología , Técnicas In Vitro , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Microelectrodos , Contracción Muscular/efectos de los fármacos , Oocitos/efectos de los fármacos , Oocitos/metabolismo , Técnicas de Placa-Clamp , Potasio/metabolismo , Unión Proteica , Receptores de GABA/metabolismo , Sodio/metabolismo , Xenopus laevis
8.
Pflugers Arch ; 453(1): 117-23, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16953425

RESUMEN

Fast ('concentration jump') applications of neurotransmitters are crucial for screening studies on ligand-gated ion channels. In this paper, we describe a method for automated fast perfusion of neurotransmitters (or drugs) during two-microelectrode voltage-clamp experiments on Xenopus oocytes. The oocytes are placed in a small bath chamber that is covered by a glass plate with two channels for the microelectrodes that are surrounded by a quartz funnel serving as a reservoir for test solutions. The oocytes are perfused in a vertical direction via the two channels in the plate. Automation of compound delivery is accomplished by means of a programmable pipetting workstation. A mean rise time for 10-90% current increase through muscle-type nACh channels of 55.0+/-1.3 ms (30 muM acetylcholine) was estimated. Automation, fast perfusion rates, and economical use of compounds ( approximately 100 mul/data point) make the system suitable for screening studies on ligand- and voltage-gated ion channels.


Asunto(s)
Técnicas de Cultivo de Célula , Cámaras de Difusión de Cultivos , Evaluación Preclínica de Medicamentos/instrumentación , Oocitos , Perfusión/instrumentación , Animales , Evaluación Preclínica de Medicamentos/métodos , Ligandos , Perfusión/métodos , Robótica , Factores de Tiempo , Xenopus
9.
Mol Pharmacol ; 69(2): 640-9, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16272224

RESUMEN

GABA(A) receptors composed of alpha(1), beta(2), gamma(1) subunits are expressed in only a few areas of the brain and thus represent interesting drug targets. The pharmacological properties of this receptor subtype, however, are largely unknown. In the present study, we expressed alpha(1)beta(2)gamma(1)-GABA(A) receptors in Xenopus laevis oocytes and analyzed their modulation by 21 ligands from 12 structural classes making use of the two-microelectrode voltage-clamp method and a fast perfusion system. Modulation of GABA-induced chloride currents (I(GABA)) was studied at GABA concentrations eliciting 5 to 10% of the maximal response. Triazolam, clotiazepam, midazolam, 2-(4-methoxyphenyl)-2,3,5,6,7,8,9,10-octahydro-cyclohepta-(b)pyrazolo[4,3-d]pyridin-3-one (CGS 20625), 2-(4-chlorophenyl)-pyrazolo[4,3-c]quinolin-3-one (CGS 9896), diazepam, zolpidem, and bretazenil at 1 microM concentrations were able to significantly (>20%) enhance I(GABA) in alpha(1)beta(2)gamma(1) receptors. Methyl-6,7-dimethoxy-4-ethyl-beta-carboline-3-carboxylate, 3-methyl-6-[3-trifluoromethyl-phenyl]-1,2,4-triazolo[4,3-b]pyridazine (Cl 218,872), clobazam, flumazenil, 5-(6-ethyl-7-methoxy-5-methylimidazo[1,2-a]pyrimidin-2-yl)-3-methyl-[1,2,4]-oxadiazole (Ru 33203), 2-phenyl-4-(3-ethyl-piperidinyl)-quinoline (PK 9084), flurazepam, ethyl-7-methoxy-11,12,13,13a-tetrahydro-9-oxo-9H-imidazo[1,5-a]pyrrolo[2,1-c] [1,4]benzodiazepine-1-carboxylate (l-655,708), 2-(6-ethyl-7-methoxy-5-methylimidazo[1,2-a]pyrimidin-2-yl)-4-methyl-thiazole (Ru 33356), and 6-ethyl-7-methoxy-5-methylimidazo[1,2-a]pyrimidin-2-yl)phenylmethanone (Ru 32698) (1 microM each) had no significant effect, and flunitrazepam and 2-phenyl-4-(4-ethyl-piperidinyl)-quinoline (PK 8165) inhibited I(GABA). The most potent compounds triazolam, clotiazepam, midazolam, and CGS 20625 were investigated in more detail on alpha(1)beta(2)gamma(1) and alpha(1)beta(2)gamma(2S) receptors. The potency and efficiency of these compounds for modulating I(GABA) was smaller for alpha(1)beta(2)gamma(1) than for alpha(1)beta(2)gamma(2S) receptors, and their effects on alpha(1)beta(2)gamma(1) could not be blocked by flumazenil. CGS 20625 displayed the highest efficiency by enhancing at 100 microM I(GABA) (alpha(1)beta(2)gamma(2)) by 775 +/- 17% versus 526 +/- 14% I(GABA) (alpha(1)beta(2)gamma(1)) and 157 +/- 17% I(GABA) (alpha(1)beta(2)) (p < 0.05). These data provide new insight into the pharmacological properties of GABA(A) receptors containing gamma(1) subunits and may aid in the design of specific ligands for this receptor subtype.


Asunto(s)
Moduladores del GABA/química , Moduladores del GABA/farmacología , Receptores de GABA-A/efectos de los fármacos , Animales , Azepinas/farmacología , Flumazenil/farmacología , Midazolam/farmacología , Oocitos/efectos de los fármacos , Subunidades de Proteína/efectos de los fármacos , Pirazoles , Triazolam/farmacología , Xenopus laevis , Ácido gamma-Aminobutírico/farmacología
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