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1.
Climacteric ; 23(2): 201-205, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31674202

RESUMO

Objective: We assessed the effect on lower urinary tract symptoms (LUTS) of a supplement containing cranberry, D-mannose and anti-inflammatory molecules in postmenopausal women undergoing surgery for cystocele.Study design: Forty postmenopausal women were randomized 1:1 to an active group receiving the nutritional supplement twice a day for 2 weeks starting from surgery, or to a control group receiving surgery only. Primary outcomes were the effectiveness in the postoperative LUTS and urinary tract infections (UTI). LUTS were investigated by a validated questionnaire (ICIQ-FLUTS) at baseline and at week 4. Secondary outcomes were the safety and tolerability of the supplement and other perioperative outcomes.Results: No significant differences were found in perioperative outcomes and in incidence of UTI. After surgery, women treated with the supplement experienced significantly better scores on the filling domain of the questionnaire. A non-significant decrease in voiding scores was also found. No adverse events were detected.Conclusion: The use of an oral supplement containing cranberry, D-mannose and anti-inflammatory molecules decreases the perception of LUTS in postmenopausal women after anterior colporraphy. Our data suggest that perioperative use of nutritional supplements may be useful in the management of postoperative LUTS.


Assuntos
Anti-Inflamatórios/administração & dosagem , Sintomas do Trato Urinário Inferior/prevenção & controle , Manose/administração & dosagem , Complicações Pós-Operatórias/prevenção & controle , Vaccinium macrocarpon , Idoso , Quimioterapia Combinada/métodos , Feminino , Humanos , Prolapso de Órgão Pélvico/cirurgia , Cuidados Pré-Operatórios/métodos , Estudos Prospectivos
2.
Case Rep Womens Health ; 22: e00104, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30976524

RESUMO

In multiple pregnancies with threatened premature delivery or preterm premature rupture of membranes (pPROM) of a single sac, prolonging pregnancy after the delivery of the first baby may improve the chances of survival of the second baby. We report the delayed delivery of a second baby in a twin pregnancy with pPROM and very premature delivery of the first baby. This condition is exceptional and there are no validated medical protocols for its management; the scientific evidence is still controversial. In our case, after the birth of the first baby, pregnancy was continued for 29 days, with monitoring of maternal and fetal parameters, which enabled the delivery of the second baby with improved neonatal outcomes. This case supports the prolongation of the pregnancy of the second twin.

3.
J Toxicol Environ Health A ; 78(6): 357-68, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25734763

RESUMO

Paraoxonase 1 (PON1) is a glycosylated enzyme that is found associated with high-density lipoproteins in blood. In addition to its endogenous antioxidant role, this enzyme is also involved in hydrolysis of organophosphate (OP) pesticides in plasma. PON1 activity shows great variability in the population as a result of a polymorphism in the coding sequence that is expressed as a Glu(Q)/Arg(R) substitution at position 192 of the amino acid sequence. The aim of this study was to determine the activity levels (phenotype) and genotype of PON1 in a group of 85 agricultural workers occupationally exposed to OP pesticides and compared to 97 control subjects without occupational exposure. Allelic and genotypic frequencies of PON1Q192R polymorphism, as well as their catalytic activities, were established for the first time in a group of agricultural Chilean workers. The Q allele was more frequently represented in our studied population (approximately 60%). The Q allele is less efficient than the R allele at metabolizing chlorpyrifos (CPF), the most widely used OP pesticide in the geographical areas where samples were obtained. Further, a large interindividual variability in PON1 activity was observed, suggesting wide variation of individual susceptibility to CPF, an issue that needs to be considered in human monitoring studies.


Assuntos
Agricultura , Arildialquilfosfatase/genética , Exposição Ocupacional , Arildialquilfosfatase/sangue , Chile , Clorpirifos , Genótipo , Humanos , Inseticidas , Polimorfismo Genético
4.
Eur Neuropsychopharmacol ; 22(8): 584-95, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22209363

RESUMO

3,4-Methylenedioxymethamphetamine (MDMA, ecstasy) is a drug of abuse that induces learning and memory deficit. However, there are no experimental data that correlate the behavioral evidence with models of synaptic plasticity such as long-term potentiation (LTP) or long-term depression (LTD). Using field potential recordings in rat hippocampal slices of young rats, we found that acute application of MDMA enhances LTP in CA3-CA1 synapses without affecting LTD. Using specific antagonists and paired-pulse facilitation protocols we observed that the MDMA-dependent increase of LTP involves presynaptic 5-HT2 serotonin receptors and postsynaptic D1/D5 dopamine receptors. In addition, the inhibition of PKA suppresses the MDMA-dependent increase in LTP, suggesting that dopamine receptor agonism activates cAMP-dependent intracellular pathways. We propose that MDMA exerts its LTP-altering effect involving a polysynaptic interaction between serotonergic and dopaminergic systems in hippocampal synapses. Our results are compatible with the view that the alterations in hippocampal LTP could be responsible for MDMA-dependent cognitive deficits observed in humans and animals.


Assuntos
Hipocampo/efeitos dos fármacos , Potenciação de Longa Duração/efeitos dos fármacos , N-Metil-3,4-Metilenodioxianfetamina/farmacologia , Neurônios/efeitos dos fármacos , Receptores Dopaminérgicos/metabolismo , Receptores 5-HT2 de Serotonina/metabolismo , Serotoninérgicos/farmacologia , Animais , Proteínas Quinases Dependentes de AMP Cíclico/antagonistas & inibidores , Proteínas Quinases Dependentes de AMP Cíclico/química , Antagonistas de Dopamina/farmacologia , Ativação Enzimática/efeitos dos fármacos , Potenciais Evocados/efeitos dos fármacos , Alucinógenos/farmacologia , Hipocampo/enzimologia , Hipocampo/metabolismo , Técnicas In Vitro , Proteínas do Tecido Nervoso/agonistas , Proteínas do Tecido Nervoso/antagonistas & inibidores , Proteínas do Tecido Nervoso/metabolismo , Neurônios/enzimologia , Neurônios/metabolismo , Terminações Pré-Sinápticas/efeitos dos fármacos , Terminações Pré-Sinápticas/enzimologia , Terminações Pré-Sinápticas/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Ratos , Ratos Sprague-Dawley , Receptores de Dopamina D1/antagonistas & inibidores , Receptores de Dopamina D1/metabolismo , Receptores de Dopamina D5/antagonistas & inibidores , Receptores de Dopamina D5/metabolismo , Antagonistas do Receptor 5-HT2 de Serotonina/farmacologia , Transmissão Sináptica/efeitos dos fármacos
5.
Endocrinology ; 149(10): 5097-106, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18566112

RESUMO

Neurological deficits in the offspring caused by human maternal hypothyroxinemia are thought to be irreversible. To understand the mechanism responsible for these neurological alterations, we induced maternal hypothyroxinemia in pregnant rats. Behavior and synapse function were evaluated in the offspring of thyroid hormone-deficient rats. Our data indicate that, when compared with controls, hypothyroxinemic mothers bear litters that, in adulthood, show prolonged latencies during the learning process in the water maze test. Impaired learning capacity caused by hypothyroxinemia was consistent with cellular and molecular alterations, including: 1) lack of increase of phosphorylated c-fos on the second day of the water maze test; 2) impaired induction of long-term potentiation in response to theta-burst stimulation to the Schaffer collateral pathway in the area 1 of the hippocampus Ammon's horn stratum radiatum, despite normal responses for input/output experiments; 3) increase of postsynaptic density protein 95 (PSD-95), N-methyl-D-aspartic acid receptor subunit 1, and tyrosine receptor kinase B levels in brain extracts; and 4) significant increase of PSD-95 at the PSDs and failure of this molecule to colocalize with N-methyl-D-aspartic acid receptor subunit 1, as it was shown by control rats. Our findings suggest that maternal hypothyroxinemia is a harmful condition for the offspring that can affect key molecular components for synaptic function and spatial learning.


Assuntos
Transtornos Cognitivos/fisiopatologia , Hipotireoidismo/fisiopatologia , Aprendizagem em Labirinto/fisiologia , Complicações na Gravidez/fisiopatologia , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia , Tiroxina/deficiência , Fatores Etários , Animais , Transtornos Cognitivos/etiologia , Proteína 4 Homóloga a Disks-Large , Feminino , Hipotireoidismo/complicações , Imidazóis , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Potenciação de Longa Duração/fisiologia , Masculino , Proteínas de Membrana/metabolismo , Fosforilação , Gravidez , Proteínas Proto-Oncogênicas c-fos/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores de N-Metil-D-Aspartato/metabolismo , Percepção Espacial/fisiologia , Sinapses/fisiologia , Tiroxina/sangue
6.
Rev Neurol ; 37(8): 739-43, 2003.
Artigo em Espanhol | MEDLINE | ID: mdl-14593633

RESUMO

INTRODUCTION AND DEVELOPMENT: Alterations of sensory experience cause large-scale re-arrangements of cortical connectivity only early in life. After a critical period that roughly ends by puberty, comparable modifications requires more invasive manipulations, including deafferentation and cortical lesions. At a cellular level, the elementary mechanisms responsible for synaptic modification appear to be available throughout life. Thus, in adults, experience dependent plasticity might be constrained additional factors, like the maturation of inhibition or changes in the extra cellular matrix. Such view is consistent with a limited, but not absent, modifiability of adult cortical circuits. This view also has interesting therapeutical implications. CONCLUSION: In this scenario, manipulation of these limiting factors, for example reducing synaptic inhibition, might be a useful strategy to enhance plasticity and to restore function in the adult cortex.


Assuntos
Plasticidade Neuronal/fisiologia , Sinapses/fisiologia , Córtex Visual/fisiologia , Animais , Humanos , Fatores de Crescimento Neural/metabolismo , Vias Neurais , Receptores de N-Metil-D-Aspartato/metabolismo
7.
Rev. neurol. (Ed. impr.) ; 37(8): 739-743, 16 oct., 2003.
Artigo em Es | IBECS | ID: ibc-28222

RESUMO

Introducción y desarrollo. Las alteraciones de la experiencia sensorial causan reordenamientos a gran escala de la conectividad cortical sólo en etapas tempranas de la vida. Tras un período crítico que aproximadamente termina en la pubertad, modificaciones similares requieren manipulaciones más invasivas, entre ellas deaferentación y lesiones corticales. En el ámbito celular, los mecanismos elementales responsables de la modificación sináptica parecen estar disponibles a lo largo de toda la vida. Por consiguiente, en adultos, la plasticidad dependiente de la experiencia podría estar limitada a factores adicionales, como la maduración de la inhibición o cambios en la matriz extracelular. Esta visión es compatible con una capacidad de modificación limitada, pero no ausente, de los circuitos corticales adultos. Esta idea también tiene interesantes implicaciones terapéuticas. Conclusión. En este escenario, la manipulación de estos factores limitantes, como la reducción de la inhibición sináptica, podría ser una estrategia útil para incrementar la plasticidad en la corteza adulta (AU)


Introduction and development. Alterations of sensory experience cause large-scale re-arrangements of cortical connectivity only early in life. After a critical period that roughly ends by puberty, comparable modifications requires more invasive manipulations, including deafferentation and cortical lesions. At a cellular level, the elementary mechanisms responsible for synaptic modification appear to be available throughout life. Thus, in adults, experience dependent plasticity might be constrained additional factors, like the maturation of inhibition or changes in the extra cellular matrix. Such view is consistent with a limited, but not absent, modifiability of adult cortical circuits. This view also has interesting therapeutical implications. Conclusion. In this scenario, manipulation of these limiting factors, for example reducing synaptic inhibition, might be a useful strategy to enhance plasticity and to restore function in the adult cortex (AU)


Assuntos
Animais , Humanos , Sinapses , Córtex Visual , Receptores de N-Metil-D-Aspartato , Fatores de Crescimento Neural , Vias Neurais , Plasticidade Neuronal
8.
J Hepatol ; 31(2): 306-14, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10453945

RESUMO

BACKGROUND/AIMS: Protein kinase CK2 (CK2) increases when cells are committed to proliferate, as in liver regeneration. This enzyme phosphorylates the tumour suppressor protein p53, whose expression controls the levels of many other cell cycle proteins. The aim of this study was to determine if CK2 was affected by p53. METHODS: Male Sprague-Dawley rats (200-250 g) were subjected to either partial hepatectomy or laparotomy and the levels and subcellular distribution of p53 were studied, following the approach used earlier for CK2. The levels of both proteins were also studied in the human cell lines HL-60 (devoid of p53) and HepG2 (with normal p53 levels) and in fibroblasts from transgenic p53-deficient mice (p53-/-) or homozygous for wild-type p53 (p53+/+). Computer-assisted search was used to detect p53 consensus sequences in genes for CK2 subunits Binding of p53 protein to some of these sequences was assayed by electrophoretic mobility shift assay. RESULTS: Rat liver p53 protein was present mainly in the fraction extracted from intact nuclei by nucleases (S1) and showed a transient increase at 6 h post partial hepatectomy, as observed previously with nuclear CK2. The human CK2a gene presents the consensus sequence for trans-activation by p53 and specific binding of p53 protein to some of these sequences was detected in vitro. Total CK2a was higher in HepG2 than in HL-60 cells but total CK2 and its cytosolic/ nuclear distribution was similar in mice (p53+/+) fibroblasts and (p53-/-) fibroblasts. CONCLUSIONS: p53 is present in the nuclease-extracted S1 fraction from liver cells, as described for CK2, and undergoes similar changes at the beginning of rat liver regeneration. However, the data on cultured cells suggest that the expression of CK2 and its subcellular localization are p53-independent events.


Assuntos
Desoxirribonucleases/metabolismo , Fibroblastos/metabolismo , Células HL-60/metabolismo , Regeneração Hepática/fisiologia , Proteínas Serina-Treonina Quinases/biossíntese , Proteína Supressora de Tumor p53/biossíntese , Animais , Western Blotting , Caseína Quinase II , Linhagem Celular , Células Cultivadas , Desoxirribonucleases/análise , Humanos , Técnicas In Vitro , Masculino , Camundongos , Camundongos Transgênicos , Ratos , Ratos Sprague-Dawley , Proteína Supressora de Tumor p53/deficiência
9.
Biochem Biophys Res Commun ; 260(1): 17-22, 1999 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-10381337

RESUMO

The catalytic subunit of protein kinase CK2 (CK2alpha) was found associated with heterogeneous nuclear ribonucleoprotein particles (hnRNPs) that contain the core proteins A2 and C1-C2. High levels of CK2 activity were also detected in these complexes. Phosphopeptide patterns of hnRNP A2 phosphorylated in vivo and in vitro by protein kinase CK2 were similar, suggesting that this kinase can phosphorylate hnRNPA2 in vivo. Binding experiments using human recombinant hnRNP A2, free human recombinant CK2alpha or CK2beta subunits, reconstituted CK2 holoenzyme and purified native rat liver CK2 indicated that hnRNP A2 associated with both catalytic and regulatory CK2 subunits, and that the interaction was independent of the presence of RNA. However, the capability of hnRNP A2 to bind to CK2 holoenzyme was lower than its binding to the isolated subunits. These data indicate that the association of CK2alpha with CK2beta interferes with the subsequent binding of hnRNP A2. HnRNP A2 inhibited the autophosphorylation of CK2beta. This effect was stronger with reconstituted human recombinant CK2 than with purified native rat liver CK2.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Animais , Caseína Quinase II , Relação Dose-Resposta a Droga , Células HeLa , Humanos , Fígado/metabolismo , Fosforilação , RNA Polimerase II/metabolismo , Ratos
10.
Biol Cell ; 89(4): 273-83, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9447702

RESUMO

Intracellular pH has been shown to be an important physiological parameter in cell cycle control and differentiation, aspects that are central to the spermatogenic process. However, the pH regulatory mechanisms in spermatogenic cells have not been systematically explored. In this work, measuring intracellular pH (pHi) with a fluorescent probe (BCECF), membrane potential with a fluorescent lipophilic anion (bisoxonol), and net movement of acid using a pH-stat system, we have found that rat round spermatids regulate pHi by means of a V-type H(+)-ATPase, a HCO3- entry pathway, a Na+/HCO3- dependent transport system, and a putative proton conductive pathway. Rat spermatids do not have functional base extruder transport systems. These pH regulatory characteristics seem specially designed to withstand acid challenges, and can generate sustained alkalinization upon acid exit stimulation.


Assuntos
Espermátides/efeitos dos fármacos , Ácidos , Álcalis , Animais , Dióxido de Carbono , Carbonatos/farmacologia , Espaço Extracelular , Concentração de Íons de Hidrogênio , Líquido Intracelular , Masculino , Prótons , Ratos , Espermátides/fisiologia
11.
J Pharmacol Exp Ther ; 279(3): 1116-22, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8968332

RESUMO

Ethanol (1-200 mM), a potent depressor of respiration and motor activity, potentiated the inhibitory Cl- current activated by glycine in 80% of the cultured mouse spinal (n = 236) neurons studied. Ethanol (100 mM) had no effect on the gamma-aminobutyric acidA current and slightly inhibited the N-methyl-D-aspartate current in these neurons. Ethanol increased the affinity of the receptors to glycine without changing the maximal amplitude of the glycine current. The EC50 was reduced from 54 +/- 3 microM in the absence of ethanol to 38 +/- 5 microM in the presence of ethanol. Activation of GTP binding proteins in the neurons with intracellular guanosine-5'-0-(2-thiotriiphosphate) (0.5 mM) enhanced the effect of ethanol, and application of a similar concentration of guanosine 5'-0-(2-thiodiphosphate had an inhibitory effect upon the current potentiation. The potentiating effect of ethanol persisted after culturing the neurons with pertussis toxin, but not with cholera toxin, an irreversible activator of Gs. Activation of cyclic AMP-dependent protein kinase by cyclic AMP and Sp-adenosine-3',5'-cyclic monophosphothioate triethylamine salt, but not of protein kinase C and protein kinase G, potentiated the glycine current. The effect of Sp-adenosine-3',5'-cyclic monophosphothioate triethylamine salt, but not of ethanol, was inhibited completely by the protein kinase A peptide inhibitor. These results suggest that ethanol potentiates the glycine activated Cl- current by modifying a signal transduction step other than protein kinase A.


Assuntos
Canais de Cloreto/efeitos dos fármacos , Etanol/farmacologia , Glicina/farmacologia , Neurônios/efeitos dos fármacos , Medula Espinal/efeitos dos fármacos , Animais , Toxina da Cólera/farmacologia , Sinergismo Farmacológico , Ativação Enzimática , Inibidores Enzimáticos/farmacologia , Guanosina 5'-O-(3-Tiotrifosfato)/análogos & derivados , Guanosina 5'-O-(3-Tiotrifosfato)/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , N-Metilaspartato/metabolismo , Neurônios/metabolismo , Toxina Pertussis , Inibidores de Proteínas Quinases , Proteínas Quinases/metabolismo , Medula Espinal/citologia , Medula Espinal/metabolismo , Fatores de Virulência de Bordetella/farmacologia , Ácido gama-Aminobutírico/metabolismo
12.
Pharmacology ; 52(6): 371-6, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8844787

RESUMO

We studied the effects of diazepam, CL 218,872, Ro 15-1788, beta-CCM and Ro 15-4513 on the gamma-aminobutyric acid-activated current in adult and newborn rat superior cervical ganglion neurons. Diazepam (10-1,000 nmol/l) potentiated the current in a concentration-dependent manner. CL 218,872 was less effective and weaker than diazepam. The other ligands reduced the amplitude of the current. These peripheral receptors might be involved in some of the side effects of benzodiazepines.


Assuntos
Neurônios/efeitos dos fármacos , Receptores de GABA-A/metabolismo , Gânglio Cervical Superior/efeitos dos fármacos , Fatores Etários , Animais , Animais Recém-Nascidos , Ansiolíticos/farmacologia , Diazepam/farmacologia , Eletrofisiologia , Flumazenil/farmacologia , Ligantes , Neurônios/metabolismo , Neurônios/fisiologia , Piridazinas/farmacologia , Ratos , Ratos Sprague-Dawley , Receptores de GABA-A/fisiologia , Gânglio Cervical Superior/metabolismo , Ácido gama-Aminobutírico/farmacologia
13.
Biochem Biophys Res Commun ; 218(1): 35-9, 1996 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-8573159

RESUMO

Protein kinase CK2 has been found in two nuclear fractions obtained after treatment of purified rat liver nuclei with nucleases (S1 fraction) and subsequently with 1.6 M NaCl (S2 fraction). In both fractions three isoforms of the alpha subunit were identified. Two of them corresponded to the classical alpha and alpha' subunits, whereas the identity of the third one (alpha 3) remains unknown. In the S1 fraction two peaks of CK2 activity were detected at 6 h (5.5 fold) and 24 h (1.9 fold) after partial hepatectomy, whereas no significant changes were found in the S2 fraction. At 6 h after laparatomy a much lower increase of CK2 in S1 fraction was also detected (2.5 fold). The increases in CK2 activity found at 6 h after hepatectomy or laparatomy were accompanied with rises in the amount of the alpha subunit.


Assuntos
Núcleo Celular/enzimologia , Regeneração Hepática/fisiologia , Fígado/enzimologia , Proteínas Serina-Treonina Quinases/metabolismo , Animais , Caseína Quinase II , Fracionamento Celular , Núcleo Celular/ultraestrutura , Hepatectomia , Cinética , Masculino , Fosforilação , Proteínas Serina-Treonina Quinases/isolamento & purificação , Ratos , Ratos Sprague-Dawley , Fatores de Tempo
14.
J Pharmacol Exp Ther ; 270(1): 61-9, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8035343

RESUMO

The effects of ethanol on the GABA (gamma-aminobutyric acid)A-activated Cl- current were studied in cultured mouse hippocampal and cortical neurons using whole-cell techniques. Ethanol (0.25-200 mM) reversibly potentiated the current in 68 of the 131 hippocampal neurons examined. Ethanol also potentiated a strychnine-sensitive glycine-activated Cl- current in hippocampal and spinal neurons. Ethanol (40 mM) enhanced the maximal response to GABA without changing the Hill coefficient (1.2) or the affinity of the receptor for GABA (EC50 = 15 vs. 14 microM). We found neurons with distinct sensitivities to ethanol, and even concentrations of 425 and 850 mM further potentiated the response induced by GABA and glycine. Ethanol was able to potentiate the GABAA current even after removing Ca++ from the external solution. The protein kinase C activator phorbol, 12 myristate, 13 acetate inhibited the amplitude of the GABA current by 73 +/- 7% of control; however, 4-alpha-phorbol, 12 myristate, 13 acetate, its inactive analog, had no effects. In addition, 2 min of preapplication of 1 microM phorbol, 12 myristate, 13 acetate reduced the ethanol-potentiation from 140 +/- 8 to 122 +/- 6%. Recordings of GABA- and glycine-activated Cl- currents showed that low concentrations of ethanol can differentially affect these receptors in a single neuron. This suggests that the GABAergic effect of ethanol is not mediated by a nonspecific change and that different mechanisms might account for the potentiation of these two ligand-activated Cl- channels by ethanol. In addition, the absence of saturation with high concentrations suggests that ethanol modulates these receptor-ion channel complexes by acting in several sites, one of which might control the state of receptor phosphorylation.


Assuntos
Canais de Cloreto/efeitos dos fármacos , Canais de Cloreto/fisiologia , Etanol/farmacologia , Glicina/farmacologia , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Receptores de GABA-A/efeitos dos fármacos , Receptores de GABA-A/fisiologia , Receptores de Glicina/fisiologia , Ácido gama-Aminobutírico/farmacologia , Animais , Cálcio/farmacologia , Células Cultivadas , Interações Medicamentosas , Hipocampo/efeitos dos fármacos , Hipocampo/fisiologia , Hipocampo/ultraestrutura , Cinética , Camundongos , Camundongos Endogâmicos C57BL , Condução Nervosa/efeitos dos fármacos , Condução Nervosa/fisiologia , Neurônios/ultraestrutura , Receptores de Glicina/efeitos dos fármacos , Acetato de Tetradecanoilforbol/farmacologia
15.
Brain Res ; 647(1): 97-105, 1994 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-8069709

RESUMO

Previous electrophysiological studies suggested that GABAA receptors in rat hippocampal neurons might be less sensitive to ethanol than mouse neurons. Therefore, we examined the effects of ethanol (0.5-850 mM) in cultured mouse (C57BL/6) and rat (Sprague-Dawley) neurons. In 35% of the mouse neurons, the Cl- current was potentiated by ethanol starting at 0.5 mM. In all of the rat neurons examined, on the other hand, the current was potentiated by concentrations starting at 200 mM. We also studied the effects of GABA and other GABAergic ligands. GABAA receptors in rat and mouse neurons displayed EC50s for GABA of 9 +/- 0.3 and 17 +/- 0.8 microM, respectively and ethanol did not significantly change these values. The EC50 for diazepam was 92 +/- 3 and 120 +/- 8 nM in rat and mouse, respectively. Pentobarbital enhanced the current with EC50s of 84 +/- 3 and 106 +/- 6 microM in rat and mouse, respectively. The sensitivity for Cl-218,872, which binds preferentially to the Type I benzodiazepine receptor, was similar in all the neurons. RO 15-4513, an inverse partial agonist to the benzodiazepine receptor, was not effective in reversing the potentiation of the Cl- current in rat neurons and only slightly reduced the potentiation in mouse neurons. The receptors in rat neurons were more sensitive to external Zn2+; the current was inhibited by 50% with a concentration of 93 +/- 3 and 244 +/- 9 microM in rat and mouse, respectively. Analysis of mRNA encoding for the gamma 2L receptor subunit showed similar levels in rat and mouse neurons.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Hipocampo/metabolismo , Ligantes , Camundongos/metabolismo , Neurônios/metabolismo , Ratos/metabolismo , Ácido gama-Aminobutírico/metabolismo , Animais , Cloretos/fisiologia , Eletrofisiologia , Etanol/farmacologia , Hipocampo/citologia , Hipocampo/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Ratos Sprague-Dawley , Receptores de GABA/efeitos dos fármacos , Receptores de GABA/metabolismo , Receptores de GABA-A/metabolismo , Especificidade da Espécie , Zinco/farmacologia , Ácido gama-Aminobutírico/farmacologia , Ácido gama-Aminobutírico/fisiologia
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