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1.
J Opt Soc Am A Opt Image Sci Vis ; 37(9): B78-B86, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32902423

RESUMO

We demonstrate an interference signal-processing method that extends the measurement range of dynamic displacement beyond half the wavelength of light without deteriorating the measurement accuracy in a phase-modulated optical interferometer. The measurement range extension is realized by the algorithm focusing on peak direction of the interference signal waveform. Deterioration of measurement accuracy is avoided by the data processing that removes noisy data sets. Performance of the proposed system is evaluated by the experiments using a pseudo-vibrator composed of a phase modulator. In the experiments using a lead zirconate titanate (PZT) device as a sample, we successfully measure the dynamic displacement of up to 3127 nm, which is larger than the light source wavelength of 1537 nm. Proof-of-principle simulations, including the evaluation of the measurement error, are also conducted, the results of which show that the measurement error of the proposed method is small in principle.

2.
Chronobiol Int ; 34(6): 753-761, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28488943

RESUMO

Blue wavelengths form the portion of the visible electromagnetic spectrum that most potently regulates circadian rhythm. We hypothesized that wearing blue-blocking (BB) glasses in the evening may influence circadian rhythm disturbances in patients with major depressive disorder (MDD), resulting in improved sleep and mood. We used a randomized placebo-controlled double-blinded design. Patients with MDD with sleep onset insomnia were randomly assigned to wearing either BB glasses or clear glasses (placebo). Patients were instructed to wear the glasses from 20:00 hours until bedtime for 2 weeks. We assessed sleep state (sleep quality on a visual analog scale, the Morningness-Eveningness Questionnaire [MEQ], and a sleep diary) and depressive symptoms at baseline and after 2 weeks. Data were analyzed with a full analysis set. In total, 20 patients were randomly assigned to the BB and placebo groups (BB group, n = 10; placebo group, n = 10). There were three dropouts (BB group, n = 1; placebo group, n = 2). At baseline, sleep quality, sleep latency (assessed via a sleep diary), and antipsychotics use differed between the groups. To take account of these differences, the baseline sleep state or depressive symptoms and antipsychotics use were used as covariates in the later analysis. The change scores for sleep quality did not show a significant improvement in the BB group compared with the placebo group (mean [standard deviation, SD] scores for BB versus placebo: 36.1 [31.7] versus 16.2 [15.1], p = 0.43), although half of the BB group showed a clear improvement in sleep quality. The change in MEQ scores did not significantly differ between the groups (p = 0.14), although there was a trend of a shift to morning type in the BB group (3.10 [4.95] points) and to evening type in the placebo group (0.50 [3.89] points). There were no statistically significant changes in depressive symptoms in either group. Across both groups, 40% of the participants reported pain or discomfort from wearing the glasses, which were available in only one size. Thus, the failure to find significant differences may have resulted from the glasses used in this study. Glasses fitted to individual patients may improve efficacy and safety. Replication of the study with a larger sample size and size-adjustable glasses is needed.


Assuntos
Ritmo Circadiano/fisiologia , Transtorno Depressivo Maior/terapia , Óculos , Transtornos do Sono do Ritmo Circadiano/terapia , Distúrbios do Início e da Manutenção do Sono/terapia , Adulto , Idoso , Cor , Transtorno Depressivo Maior/complicações , Transtorno Depressivo Maior/diagnóstico , Método Duplo-Cego , Feminino , Humanos , Luz , Masculino , Pessoa de Meia-Idade , Sono/fisiologia , Transtornos do Sono do Ritmo Circadiano/diagnóstico , Transtornos do Sono do Ritmo Circadiano/etiologia , Distúrbios do Início e da Manutenção do Sono/diagnóstico , Distúrbios do Início e da Manutenção do Sono/etiologia , Adulto Jovem
3.
Artigo em Inglês | MEDLINE | ID: mdl-25772167

RESUMO

Gram-negative bacteria are one of the major pathogens associated with severe sepsis and septic shock. LPS is a component of the outer membrane of gram-negative bacteria, which causes a systemic, uncontrolled inflammatory response in infected subjects. In microcirculation it manifests multiple insults, including leukocyte and platelet adhesion, ROS and protease overproduction, mast cell degranulation, endothelium hyperpermeabilty, hemorrhage, and microthrombi formation, ultimately results in multiorgan dysfunction, DIC, refractory shock and even death. TCM has been used in China, Korea, Japan and other Asian countries for treatment of a wide range of diseases. In China, the usage of compound traditional preparation to treat inflammation-related diseases dates back to the Han Dynasty and the medical formulary had been developed thousands of years before, which recorded a great number of classical prescriptions for treatment with infectious diseases. This review will summarize the up to date works with respect to the ameliorating effects of compound and single traditional Chinese medicine and active components on LPS-induced inflammation, including clinical trial and experimental studies regarding multiorgan injury and underlying mechanisms.

4.
Asian J Psychiatr ; 6(3): 200-7, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23642976

RESUMO

Japan approved clozapine for treatment-resistant schizophrenia in June 2009. The aim of this study was to evaluate clozapine's efficacy and tolerability in Japanese patients. A twelve-week, single-arm clinical trial of clozapine in treatment-resistant schizophrenia inpatients, was conducted under real-world conditions using raters masked for type of antipsychotic. Thirty-eight patients were recruited, with 33 (86.8%) completing the trial. At week 12, clozapine was associated with significant improvement in the Positive and Negative Syndrome Scale (PANSS) total (p < 0.0001), PANSS positive (p < 0.0001), negative (p = 0.0055) and general subscale scores (p < 0.0001). Significant improvements occurred in all PANSS scores by week 4, the first post-baseline psychopathology rating. Altogether, 50.0% of patients showed ≥20% reduction in PANSS total score, 20.6% had ≥30% reduction and 14.7% had >40% reduction. Eighteen patients (47.4%) were discharged before week 12. However, all patients experienced ≥1 adverse event. Two of 38 patients (5.2%) dropped out due to moderate leucopenia and one of them developed agranulocytosis after stopping clozapine. However, both patients recovered. Eight adverse events (hypersalivation, fatigue, sedation, constipation, insomnia, nausea/vomiting, chest pain and leucopenia) were observed in 34-79% of patients. These findings suggest that clozapine is beneficial in Japanese treatment-resistant schizophrenia patients. However, attention should be paid to patients' adverse events.


Assuntos
Antipsicóticos/administração & dosagem , Clozapina/administração & dosagem , Esquizofrenia/tratamento farmacológico , Antipsicóticos/efeitos adversos , Clozapina/efeitos adversos , Esquema de Medicação , Resistência a Medicamentos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
5.
Hum Psychopharmacol ; 28(3): 220-9, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23553665

RESUMO

OBJECTIVES: We investigated whether nicotine dependence affects these endophenotypes in Japanese schizophrenia patients and whether alpha4 and beta2 subunits of neuronal nicotinic acetylcholine receptor genes (alpha4 subunit of the nAChR gene (CHRNA4)/beta2 subunit of the nAChR gene (CHRNB2)) were associated with nicotine dependence in patients (n = 100) and healthy controls (n = 107). METHODS: First, in patients, we evaluated cognitive function, using the Brief Assessment of Cognition in Schizophrenia, and acoustic startle responses. Second, we evaluated the severity of nicotine dependence, using the Tobacco Dependence Screener, the Fagerström Test for Nicotine Dependence, and the Brinkman index in current smokers in both groups. Third, we evaluated the relationship between acoustic startle responses, cognitive function, and severity of nicotine dependence. Finally, using 12 tagging single-nucleotide polymorphisms in each the CHRNA4/CHRNB2, we used multiple linear regression analysis to examine the association between nicotine dependence measures and each selected single-nucleotide polymorphism. RESULTS: The presence and severity of nicotine dependence were associated with verbal memory and executive function in schizophrenia patients. However, nicotine dependence was not correlated with any acoustic startle response. In addition, rs755203 and rs1044397 in CHRNA4 were associated with nicotine dependence in healthy controls. CONCLUSIONS: Nicotine dependence might influence the level of verbal memory and executive function in schizophrenia patients. In addition, rs755203 and rs1044397 in CHRNA4 might play a role in the pathophysiology of nicotine dependence in healthy controls in the Japanese population.


Assuntos
Cognição , Receptores Nicotínicos/genética , Esquizofrenia/fisiopatologia , Tabagismo/fisiopatologia , Adulto , Idoso , Estudos de Casos e Controles , Endofenótipos , Função Executiva/fisiologia , Feminino , Humanos , Japão , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Reflexo de Sobressalto , Índice de Gravidade de Doença , Tabagismo/genética
6.
Neuromolecular Med ; 14(2): 131-8, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22454047

RESUMO

Recently, schizophrenia endophenotypes have been actively investigated to better understand the pathophysiology of schizophrenia. Past studies have shown that cognitive functions, including working memory and executive function, correlate with acoustic startle responses, such as prepulse inhibition (PPI), in patients with schizophrenia. The aim of this study was to investigate the relationship between cognitive functions and acoustic startle response in Japanese patients with schizophrenia. In 100 patients with schizophrenia, we evaluated cognitive function, using the Brief Assessment of Cognition in Schizophrenia, Japanese-language version (BACS-J), and acoustic startle responses, including acoustic startle reflex, habituation, and PPI (three different intensities: 82, 86, and 90 dB SPL, equivalent to signal-to-noise ratios of +12, +16, and +20 dB, respectively). Using multiple regression analysis, we examined the relationship between acoustic startle responses and BACS-J primary measures or composite score. Level of attention was associated with magnitude of habituation in schizophrenia (P = 0.0009, ß = -0.357). None of the other domains of cognitive function were significantly associated with any measure of acoustic startle response. This included attention regarding ASR (P = 0.513), PPI (P = 0.521-0.842), verbal memory (P = 0.423-0.981), working memory (P = 0.312-0.966), motor speed (P = 0.323-0.955), verbal fluency (P = 0.125-0.920), executive function (P = 0.118-0.470), and the BACS-J composite score (P = 0.230-0.912). In this first investigation of the relationship between cognitive functions and acoustic startle responses in Japanese patients with schizophrenia, attentional deficits correlated highly with the level of habituation. However, a replication study using other population samples is required to further investigate this relationship.


Assuntos
Cognição , Reflexo de Sobressalto , Psicologia do Esquizofrênico , Estimulação Acústica/psicologia , Adulto , Idoso , Povo Asiático/psicologia , Atenção , Feminino , Habituação Psicofisiológica , Humanos , Masculino , Memória de Curto Prazo , Pessoa de Meia-Idade , Testes Neuropsicológicos
7.
Psychopharmacology (Berl) ; 209(2): 185-90, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20177883

RESUMO

BACKGROUND: Studies have also shown that differences in the kind of the antipsychotics influenced disruption of the sensorimotor gating system, including prepulse inhibition (PPI), acoustic startle reflex (ASR), and habituation (HAB). We investigated the influence on startle response in chronic schizophrenia in 20 patients with schizophrenia taking risperidone, 21 patients with schizophrenia taking olanzapine, and 20 patients with schizophrenia taking aripiprazole. METHOD: The patients who participated in this study were on maintenance therapy with only one antipsychotic drug for 4 months. We performed the test for the association between all PPI measures (ASR, HAB, and PPI at prepulse sound pressure intensities of 82, 86, and 90 dB) and each the risperidene, olanzapine, and aripiprazole groups, with analysis of covariance (ANCOVA; using age, duration of illness, and daily dose of the antipsychotic as covariates). Also, when significant difference was detected in ANCOVA, the differences of PPI measures between every pairs of two drug groups were tested as a post hoc analysis with the use of t test and Bonferroni's correction of multiple tests. RESULT: We found that PPI90 showed significant differences with ANCOVA among patients with schizophrenia taking each of the antipsychotics. When we performed a post hoc analysis for PPI90, the value was higher in the aripiprazole group than in the olanzapine group and higher in the risperidone group than in the olanzapine group. CONCLUSION: Aripiprazole and risperidone may improve PPI90. ASR, HAB, PPI82, and PPI86 were no different among the Japanese schizophrenic patient groups with different antipsychotics.


Assuntos
Antipsicóticos/uso terapêutico , Benzodiazepinas/uso terapêutico , Piscadela/efeitos dos fármacos , Piperazinas/uso terapêutico , Quinolonas/uso terapêutico , Reflexo de Sobressalto/efeitos dos fármacos , Risperidona/uso terapêutico , Esquizofrenia/tratamento farmacológico , Estimulação Acústica , Adulto , Idoso , Aripiprazol , Povo Asiático , Feminino , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Olanzapina , Esquizofrenia/etnologia , Esquizofrenia/fisiopatologia , Psicologia do Esquizofrênico , Resultado do Tratamento
8.
Neurosci Res ; 66(4): 340-4, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20025912

RESUMO

Several investigators have reported cognitive dysfunction in chronic schizophrenia that was associated with insight and social skills. Such cognitive dysfunction seriously hinders an immediate return to normal life. Recently, Kaneda et al. reported that the Brief Assessment of Cognition in Schizophrenia, Japanese-language version (BACS-J) was superior in the evaluation of the cognitive function. We investigated which clinical factors (age, sex, duration of illness, level of education, smoking status, the Positive and Negative Syndrome Scale (PANSS) score and medication dosage) affected cognitive dysfunction in 115 Japanese schizophrenic patients, with the use of multiple regression analysis. We detected an association between composite score, verbal memory, working memory and executive function and PANSS total score. Moreover, most cognitive tasks were associated with a negative PANSS score but not a positive PANSS score or general score. We also showed an association between age and verbal fluency and attention in schizophrenia. In addition, anxiolytics/hypnotics (diazepam-equivalent) were associated with composite score, working memory and motor speed. In conclusion, cognitive function was associated with PANSS score, especially negative PANSS score. Because anxiolytics/hypnotics might have a detrimental influence on cognitive function, we strongly suggest that the use of anxiolytics/hypnotics be reduced in schizophrenics as much as possible.


Assuntos
Cognição , Esquizofrenia/fisiopatologia , Psicologia do Esquizofrênico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos
9.
Neurosci Res ; 65(3): 259-62, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19660506

RESUMO

Prepulse inhibition (PPI) deficit, the acoustic startle reflex (ASR) and habituation (HAB) impairment are considered to be endophenotypes for schizophrenia. The recent two studies have reported that a PPI deficit was detected in Japanese schizophrenic patients. We replicated that study using larger samples (115 schizophrenic patients and 111 normal controls) than the original study and a method same as original study. A startle response monitoring system was used to deliver acoustic startle stimuli, and to record and score the electromyographic activity of the orbicularis oculi muscle. We evaluated the startle measures of mean magnitude of ASR, HAB, and PPI at prepulse sound pressure intensities of 82dB (PPI82), 86dB (PPI86), and 90dB (PPI90). ASR was significantly different between schizophrenic patients and controls. HAB and all PPI session data from schizophrenic patients were significantly lower than in controls. In addition, we detected significant differences for ASR, HAB and each PPI (82, 86 and 90dB) between schizophrenic patients and controls with the use of multiple regression analysis. The gender and smoking state were not correlated with ASR, HAB or any PPI in multiple regression analysis. In conclusion, we were able to replicate the finding of HAB impairment and PPI deficit in chronic Japanese schizophrenic patients.


Assuntos
Inibição Neural/fisiologia , Reflexo Anormal/fisiologia , Reflexo de Sobressalto/fisiologia , Esquizofrenia/fisiopatologia , Filtro Sensorial/fisiologia , Estimulação Acústica , Adulto , Povo Asiático , Vias Auditivas/fisiopatologia , Limiar Auditivo/fisiologia , Encéfalo/fisiopatologia , Doença Crônica , Estudos de Coortes , Eletromiografia , Músculos Faciais/inervação , Músculos Faciais/fisiopatologia , Feminino , Habituação Psicofisiológica/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Análise de Regressão , Psicologia do Esquizofrênico , Distribuição por Sexo
10.
Am J Physiol Gastrointest Liver Physiol ; 288(3): G557-63, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15499081

RESUMO

The proximal duodenum is exposed to extreme elevations of P(CO(2)) because of the continuous mixture of secreted HCO(3)(-) with gastric acid. These elevations (up to 80 kPa) are likely to place the mucosal cells under severe acid stress. Furthermore, we hypothesized that, unlike most other cells, the principal source of CO(2) for duodenal epithelial cells is from the lumen. We hence examined the effect of elevated luminal P(CO(2)) on duodenal HCO(3)(-) secretion (DBS) in the rat. DBS was measured by the pH-stat method. For CO(2) challenge, the duodenum was superfused with a high Pco(2) solution. Intracellular pH (pH(i)) of duodenal epithelial cells was measured by ratio microfluorometry. CO(2) challenge, but not isohydric solutions, strongly increased DBS to approximately two times basal for up to 1 h. Preperfusion of the membrane-permeant carbonic anhydrase inhibitor methazolamide, or continuous exposure with indomethacin, fully inhibited CO(2)-augmented DBS. Dimethyl amiloride (0.1 mM), an inhibitor of the basolateral sodium-hydrogen exchanger 1, also inhibited CO(2)-augumented DBS, although S-3226, a specific inhibitor of apical sodium-hydrogen exchanger 3, did not. DIDS, an inhibitor of basolateral sodium-HCO(3)(-) cotransporter, also inhibited CO(2)-augemented DBS, as did the anion channel inhibitor 5-nitro-2-(3-phenylpropylamino) benzoic acid. CO(2) decreased epithelial cell pH(i), followed by an overshoot after removal of the CO(2) solution. We conclude that luminal CO(2) diffused in the duodenal epithelial cells and was converted to H(+) and HCO(3)(-) by carbonic anhydrase. H(+) initially exited the cell, followed by secretion of HCO(3)(-). Secretion was dependent on a functioning basolateral sodium/proton exchanger, a functioning basolateral HCO(3)(-) uptake mechanism, and submucosal prostaglandin generation and facilitated hydration of CO(2) into HCO(3)(-) and H(+).


Assuntos
Bicarbonatos/metabolismo , Dióxido de Carbono/metabolismo , Duodeno/metabolismo , Ácido 4,4'-Di-Isotiocianoestilbeno-2,2'-Dissulfônico/farmacologia , Animais , Proteínas de Transporte de Ânions/metabolismo , Anidrases Carbônicas/metabolismo , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Inibidores de Ciclo-Oxigenase/farmacologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Concentração de Íons de Hidrogênio , Processamento de Imagem Assistida por Computador , Indometacina/farmacologia , Masculino , Nitrobenzoatos/farmacologia , Prostaglandina-Endoperóxido Sintases/metabolismo , Ratos , Ratos Sprague-Dawley , Trocadores de Sódio-Hidrogênio/metabolismo
11.
Am J Physiol Gastrointest Liver Physiol ; 286(6): G891-8, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-14764447

RESUMO

Luminal exposure to concentrated acid, the most accepted physiological stimulus for duodenal bicarbonate secretion (DBS), cannot be used with in vitro preparations due to potential tissue damage. We thus examined whether exposure to PGE(2), a well-characterized physiological duodenal secretagogue, could mimic the effects of acid perfusion. DBS was measured in C57/BL mice by pH-stat/back-titration and measurement of total dissolved CO(2) concentration ([CO(2)](t)). Anion transport inhibitor DIDS, anion channel inhibitor 5-nitro-2-(3-phenylpropylamino)benzoic acid (NPPB), carbonic anhydrase inhibitor methazolamide, and nonselective cyclooxygenase inhibitor indomethacin were used to inhibit separate components of HCO(3)(-) secretory pathway. Baseline DBS was not altered by exposure to methazolamide (0.1 mM) but was slightly reduced by DIDS (0.5 mM). DBS and [CO(2)](t) increased after acid and PGE(2) exposure. DIDS (0.5 mM) and NPPB (0.2 mM) abolished acid-induced DBS increase. Methazolamide (0.1 mM) and DIDS inhibited acid-induced [CO(2)](t) increase. DIDS, NPPB, or methazolamide had little effect on DBS in response to high concentration PGE(2) (100 microg/ml). Low concentration PGE(2) (1 microg/ml) increased DBS that was inhibited by DIDS, NPPB, and methazolamide. Pretreatment with indomethacin (5 mg/kg) inhibited DBS induced by acid exposure but not by PGE(2). High-dose PGE(2) substantially increases DBS by a mechanism that appears to be different than secretory response to luminal acid perfusion. Secretory response to low-dose PGE(2), at least in terms of inhibitor profile, closely resembles secretion in response to perfusion of physiological acid concentrations and may be a useful stimulus for in vitro study of DBS in isolated mouse duodenum.


Assuntos
Ácidos/metabolismo , Bicarbonatos/metabolismo , Dinoprostona/administração & dosagem , Duodeno/efeitos dos fármacos , Duodeno/metabolismo , Ácido 4,4'-Di-Isotiocianoestilbeno-2,2'-Dissulfônico/farmacologia , Animais , Ânions/metabolismo , Transporte Biológico/efeitos dos fármacos , Inibidores da Anidrase Carbônica/farmacologia , Relação Dose-Resposta a Droga , Canais Iônicos/antagonistas & inibidores , Masculino , Metazolamida/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Nitrobenzoatos/farmacologia
12.
Am J Physiol Gastrointest Liver Physiol ; 286(1): G102-9, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12881227

RESUMO

We examined the effect of inhibition of Na+/H+ exchange (NHE) on duodenal bicarbonate secretion (DBS) in rats to further understand DBS regulation. DBS was measured by using the pH-stat method and by using CO2-sensitive electrodes. 5-(N,N-dimethyl)-amiloride (50 microM; DMA), a concentration that selectively inhibits the NHE isoforms NHE1 and NHE2, but not NHE3, did not affect DBS. Nevertheless, 3 mM DMA, a higher concentration that inhibits NHE1, NHE2, and NHE3, significantly increased DBS. Moreover, S1611 and S3226, both specific inhibitors of NHE3 only, or perfusion with Na+-free solutions, dose dependently increased DBS, as measured by pH-stat and CO2-sensitive electrode, without affecting intracellular pH. Coperfusion with 0.1 microM indomethacin, 0.5 mM DIDS, or 1 mM methazolamide did not affect S3226-induced DBS. Nevertheless, coperfusion with 0.1 and 0.3 mM 5-nitro-2-(3-phenylpropylamino) benzoic acid, which inhibits the cystic fibrosis transmembrane conductor regulator (CFTR), dose dependently inhibited S3226-induced DBS. In conclusion, only specific apical NHE3 inhibition increased DBS, whereas prostaglandin synthesis, Na+-HCO3- cotransporter activation, or intracellular HCO3- formation by carbonic anhydrase was not involved. Because NHE3 inhibition-increased DBS was inhibited by an anion channel inhibitor and because reciprocal CFTR regulation has been previously shown between NHE3 and apical membrane anion transporters, we speculate that NHE3 inhibition increased DBS by altering anion transporter function.


Assuntos
Bicarbonatos/metabolismo , Duodeno/metabolismo , Inibidores Enzimáticos/farmacologia , Trocadores de Sódio-Hidrogênio/antagonistas & inibidores , Ácido 4,4'-Di-Isotiocianoestilbeno-2,2'-Dissulfônico/farmacologia , Amilorida/farmacologia , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Dióxido de Carbono/metabolismo , Dióxido de Carbono/fisiologia , Inibidores da Anidrase Carbônica/farmacologia , Citofotometria , Duodeno/efeitos dos fármacos , Duodeno/enzimologia , Guanidinas/farmacologia , Concentração de Íons de Hidrogênio , Processamento de Imagem Assistida por Computador , Indometacina/farmacologia , Masculino , Metacrilatos/farmacologia , Metazolamida/farmacologia , Nitrobenzenos/farmacologia , Ratos , Ratos Sprague-Dawley , Trocador 3 de Sódio-Hidrogênio
13.
Pharmacology ; 67(2): 99-105, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12566854

RESUMO

We examined the effect of several protein kinase inhibitors, such as staurosporine for protein kinase C (PKC), H-89 for protein kinase A (PKA) and genistein for tyrosine kinase (TK) on acid-induced duodenal bicarbonate secretion (DBS) in rats. HCO(-)(3) secretion was measured using the pH-stat method. Mucosal acidification was performed by perfusing the duodenal loop for 10 min with pH 2.2 HCl. Indomethacin, staurosporine and genistein were added to acidified saline and then perfused, respectively. In some cases, genistein and phorbol 12-myristate 13-acetate (PMA) were added to the luminal solution to examine the effect on basal duodenal HCO(-)(3) secretion. PGE(2) (PKA pathway) and PMA (PKC pathway) stimulate basal DBS. Indomethacin, H-89, staurosporine and genistein inhibit acid-induced DBS, indicating involvement of the cyclooxygenase, PKA, PKC and TK pathways.


Assuntos
Bicarbonatos/metabolismo , Duodeno/enzimologia , Duodeno/metabolismo , Ácido Clorídrico/farmacologia , Proteínas Quinases/fisiologia , Animais , Dinoprostona/farmacologia , Duodeno/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Membro Posterior , Masculino , Inibidores de Proteínas Quinases , Ratos , Ratos Sprague-Dawley , Tempo de Reação/efeitos dos fármacos
14.
World J Gastroenterol ; 6(5): 651-658, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11819669

RESUMO

AIM:To examine whether nizatidine stimulates duodenal HCO(3)(-) secretion in rats by inhibiting AChE activity.METHODS:Under pentobarbital anesthesia, a proximal duodenal loop was perfused with saline, and the HCO(3)(-) secretion was measured at pH 7.0 using a pH-stat method and by adding 10mM HCl. Nizatidine, neostigmine, carbachol or famotidine was administered i.v. as a single injection.RESULTS:Intravenous administration of nizatidine (3-30mg/kg) dose-dependently increased duodenal HCO(3)(-) secretion, and the effect at 10mg/kg was equivalent to that obtained by carbachol at 0.01mg/kg. This nizatidine action was observed at the same dose range that inhibited acid secretion and enhanced gastric motility, mimicked by i.v. injection of neostigmine(0.03mg/kg), and significantly attenuated by bilateral vagotomy and prior s.c. administration of atropine but not by indomethacin, a cyclooxygenase inhibitor, or NG-nitro-L-arginine methyl ester, a NO synthase inhibitor. The HCO(3)(-) secretory response to acetylcholine (0.001mg/kg) was significantly potentiated by the concurrent administration of nizatidine (3mg/kg,i.v.). The IC(50) of nizatidine for AChE of rat erythrocytes was 1.4·10(-6) M, about 12 times higher than that of neostigmine. Neither famotidine (> 10(-3) M, 30mg/kg, i.v.) nor cisapride (> 10(-3) M,3mg/kg, i.v.) had any influence on AChE activity or duodenal HCO(3)(-) secretion. Duodenal damage induced by acid perfusion (100mM HCl for 4h) in the presence of indomethacin was significantly prevented by nizatidine and neostigmine, at the doses that increased the HCO(3)(-)secretion.CONCLUSION:Nizatidine stimulates duodenal HCO(3)(-) secretion, in both vagal dependent and atropine sensitive manners, and the action is associated with the anti-AChE activity of this agent.

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