RESUMO
Stress-associated immune responses were compared between young (8 weeks of age) and old (56 weeks) mice. Since stress suppresses the conventional immune system (i.e. T and B cells) but inversely activates the primordial immune system (i.e. extrathymic T cells, NKT cells, and granulocytes), these parameters were analysed after restraint stress for 24 h. The thymus became atrophic as a function of age, and an age-related increase in the number of lymphocytes was seen in the liver. Although the number of lymphocytes in both the thymus and liver decreased as the result of stress, the magnitude was much more prominent in the thymus. To determine stress-resistant lymphocyte subsets, two-colour immunofluorescence tests were conducted in the liver and spleen. NKT cells were found to be such cells in the liver of young mice. On the other hand, an infiltration of granulocytes due to stress was more prominent in the liver of old mice than in young mice. Liver injury as a result of stress was prominent in young mice. This age-related bias in the function of NKT cells and granulocytes seemed to be associated with a difference in the responses of catecholamines (high in old mice) and corticosterone (high in young mice) after stress. Indeed, an injection of adrenaline mainly induced the infiltration of granulocytes while that of cortisol activated NKT cells. The present results suggest the existence of age-related bias in the function of NKT cells and granulocytes after stress and that such bias might be produced by different responses of sympathetic nerves and steroid hormones between young and old mice.
Assuntos
Envelhecimento/imunologia , Granulócitos/imunologia , Hidrocortisona/análogos & derivados , Células Matadoras Naturais/imunologia , Estresse Fisiológico/imunologia , Animais , Citotoxicidade Imunológica , Epinefrina/farmacologia , Hidrocortisona/farmacologia , Fígado/imunologia , Ativação Linfocitária/imunologia , Subpopulações de Linfócitos/imunologia , Tecido Linfoide/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Restrição Física , Baço/imunologia , Sistema Nervoso Simpático/imunologiaRESUMO
Genetic factors have been implicated in playing a significant role in susceptibility to anorexia nervosa (AN). Among many candidate genes for AN, an association with the A allele of the -1438G/A polymorphism in the promoter region of the 5-HT2A receptor has been reported. However, these findings are controversial and all patients studied to date have been Caucasian. This study was designed to determine whether this association is reproducible in Japanese subjects. This case-control study of a cohort of 75 female Japanese AN sufferers and 127 normal female control subjects revealed no significant association between the 5-HT2A promoter polymorphism and AN. Thus, at least for Japanese subjects, the A-allele of the -1438G/A polymorphism in the promoter region of the 5-HT2A receptor gene does not contribute to a predisposition to AN.
Assuntos
Anorexia Nervosa/genética , Povo Asiático/genética , Polimorfismo Genético , Regiões Promotoras Genéticas , Receptores de Serotonina/genética , Alelos , Estudos de Casos e Controles , Estudos de Coortes , DNA/sangue , DNA/genética , Feminino , Frequência do Gene , Predisposição Genética para Doença/genética , Humanos , Japão , Polimorfismo de Nucleotídeo Único , Receptor 5-HT2A de Serotonina , Valores de ReferênciaRESUMO
Elevated plasma tumor necrosis factor-alpha (TNFalpha) levels and enhanced spontaneous TNFalpha release from peripheral blood mononuclear cells in patients with anorexia nervosa (AN) have been reported. TNFalpha activates the hypothalamic-pituitary-adrenal axis and reduces food intake, which is characteristic of eating disorders. Recently, three novel polymorphisms in the 5'-flanking region of the TNFalpha gene were reported at positions -1031 (T --> C substitution), -863 (C --> A) and -857 (C --> T). Differences in these alleles are reportedly related to altered TNFalpha-transcriptional promoter activity. Therefore, we performed a case-control association analysis to determine whether any of those three polymorphisms in the TNFalpha promoter region were involved in a predisposition to AN. The results of our analysis of a cohort of 79 female Japanese AN sufferers and 127 normal female control subjects provide no support for the hypothesis that -1031T/C, -863 C/A and -857C/T polymorphisms in the TNFalpha gene promoter region influence the susceptibility to AN.
Assuntos
Anorexia Nervosa/genética , Polimorfismo Genético , Regiões Promotoras Genéticas , Fator de Necrose Tumoral alfa/genética , Adulto , Idade de Início , Anorexia Nervosa/sangue , Índice de Massa Corporal , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Feminino , Triagem de Portadores Genéticos , Genótipo , Humanos , Razão de Chances , Polimorfismo de Nucleotídeo Único , Valores de Referência , Transcrição Gênica , Fator de Necrose Tumoral alfa/metabolismoRESUMO
BACKGROUND: Motor skill learning may be impaired in schizophrenia. While functional brain imaging studies have shown reduced activation during motor task performance in schizophrenic patients, brain activity changes with motor skill learning in these patients have not been studied by functional imaging. METHODS: A sequential complex motor task involving the right hand was performed by nine medicated schizophrenic patients and 10 age-matched healthy controls. Functional magnetic resonance images were obtained using a gradient echo, echoplanar imaging (EPI) pulse sequence before and after 1 week of training in performing the task. RESULTS: Bilaterally, patients showed significantly less blood oxygenation level-dependent (BOLD) signal response in the premotor area (PMA) before beginning motor training than controls. BOLD signal response increased in the left PMA of schizophrenic patients after 1 week of motor training; in contrast, the signal decreased in the left PMA of control subjects. Training effects concerning the number of finger movement sequences achieved did not differ between groups. Daily neuroleptic dose did not significantly affect changes with training in BOLD signal response in the PMA. CONCLUSIONS: These preliminary results suggest that schizophrenic patients have dysfunction of neural networks in areas including the PMA that are involved in executing a complex motor task. In terms of brain activity, motor learning may be less efficient or slower in the patients than in healthy subjects.
Assuntos
Encéfalo/fisiopatologia , Aprendizagem/fisiologia , Imageamento por Ressonância Magnética , Transtornos Psicomotores/etiologia , Esquizofrenia/complicações , Esquizofrenia/fisiopatologia , Adolescente , Adulto , Encéfalo/patologia , Feminino , Lateralidade Funcional/fisiologia , Humanos , Masculino , Transtornos Psicomotores/diagnóstico , Índice de Gravidade de DoençaRESUMO
BACKGROUND: It is possible that psychopathological differences exist between the restricting and bulimic forms of anorexia nervosa. We investigated localized differences of brain blood flow of anorexia nervosa patients using SPECT image analysis with statistic parametric mapping (SPM) in an attempt to link brain blood flow patterns to neurophysiologic characteristics. METHODS: The subjects enrolled in this study included the following three groups: pure restrictor anorexics (AN-R), anorexic bulimics (AN-BP), and healthy volunteers (HV). All images were transformed into the standard anatomical space of the stereotactic brain atlas, then smoothed. After statistical analysis of each brain image, the relationships among images were evaluated. RESULTS: SPM analysis of the SPECT images revealed that the blood flow of frontal area mainly containing bilateral anterior cingulate gyri (ACC) was significantly decreased in the AN-R group compared to the AN-BP and HV groups. CONCLUSIONS: These findings suggest that some localized functions of the ACCare possibly relevant to the psychopathological aspects of AN-R.
Assuntos
Anorexia Nervosa/diagnóstico por imagem , Anorexia Nervosa/fisiopatologia , Bulimia/fisiopatologia , Giro do Cíngulo/irrigação sanguínea , Tomografia Computadorizada de Emissão de Fóton Único/estatística & dados numéricos , Glicemia/análise , Índice de Massa Corporal , Bulimia/diagnóstico por imagem , Feminino , Lobo Frontal/irrigação sanguínea , Lobo Frontal/diagnóstico por imagem , Lobo Frontal/fisiopatologia , Giro do Cíngulo/diagnóstico por imagem , Giro do Cíngulo/fisiopatologia , Hematócrito , Humanos , Fluxo Sanguíneo Regional , Tecnécio Tc 99m ExametazimaRESUMO
The number of patients suffering from anorexia nervosa is rising steadily. More than 90 percent of patients are female in preadolescents or adolescents. AN is characterized by abnormal eating behavior and excessive loss of weight. The self-esteem is highly dependent on their body shape and weight. The purposes of behavior therapy for AN are to remove various types of avoidance behavior, to reestablish desirable eating behavior and social skill behavior. The course and outcome of AN are variable. Of patients admitted to our hospital to receive behavior therapy, 60 percent are mostly recovered, 30 percent exhibit a fluctuating pattern of weight gain followed by relapse, and 10 percent are chronically deteriorating course of the illness over many years. The long-term mortality from AN is about 6 percent.
Assuntos
Anorexia Nervosa , Adolescente , Adulto , Anorexia Nervosa/terapia , Criança , Feminino , Humanos , MasculinoRESUMO
OBJECTIVE: To clarify the differences in immunological and psychobehavioral characteristics of HTLV-1 carriers and non-carriers with persistently low natural killer (NK) cell activity. METHODS: The individuals with persistently low NK cell activity were divided into HTLV-1 carriers and non-carriers. NK cell activity, lymphocytic proliferation, lymphocyte subsets (CD4+, CD8+, CD16+, CD20+, CD56+), and psychobehavioral responses were examined. PATIENTS: Of 296 outpatients with physical complaints, 30 patients with persistently low NK cell activity (10 HTLV-1 carriers and 20 HTLV-1 non-carriers) and 20 healthy controls negative for HTLV-1 antibody and with normal NK cell activity were randomly selected. RESULTS: In HTLV-1 carriers with persistently low NK cell activity, no significant differences were observed in NK cell subsets (CD16+ and CD56+) and psychobehavioral responses compared with the healthy controls. In HTLV-1 non-carriers, NK cell subsets were significantly low, and depression, anxiety and fatigue were significantly greater than in healthy controls. CONCLUSIONS: These findings suggest that persistently e low NK cell activity in HTLV-1 carriers might be reduced due to the HTLV-1 infection. On the other hand, the reduction in the NK cell activity in HTLV-1 non-carriers appears a to be related to depression, anxiety, and fatigue.
Assuntos
Comportamento , Portador Sadio/imunologia , Portador Sadio/psicologia , Infecções por HTLV-I/imunologia , Infecções por HTLV-I/psicologia , Células Matadoras Naturais/fisiologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
OBJECTIVE: The authors' goal was to investigate the effect of imagining food on the regional cerebral blood flow (rCBF) of anorexia nervosa patients with and without habitual binge/purge behavior. METHOD: The subjects included seven female patients with purely restrictive anorexia, seven female patients with anorexia and habitual binge/purge behavior, and seven healthy women. Single photon emission computed tomography examination was performed before and after the subjects were asked to imagine food. Changes in rCBF count ratios (percent change) were then calculated and compared. The subjects were also asked to assess their degree of fear regarding their control of food intake. RESULTS: The anorexia nervosa patients with habitual binge/purge behavior had a significantly higher percent change in the inferior, superior, prefrontal, and parietal regions of the right brain than the patients with purely restrictive anorexia and the healthy volunteers. The patients with habitual binge/purge behavior also had the highest level of apprehension in regard to food intake. CONCLUSIONS: Specific activation in cortical regions suggests an association between habitual binge/purge behavior and the food recognition process linked to anxiety in patients with anorexia nervosa.
Assuntos
Anorexia Nervosa/psicologia , Encéfalo/irrigação sanguínea , Encéfalo/fisiologia , Bulimia/psicologia , Alimentos , Imaginação/fisiologia , Tomografia Computadorizada de Emissão de Fóton Único/estatística & dados numéricos , Adulto , Anorexia Nervosa/diagnóstico , Anorexia Nervosa/epidemiologia , Encéfalo/diagnóstico por imagem , Bulimia/diagnóstico , Bulimia/epidemiologia , Comorbidade , Ingestão de Alimentos/psicologia , Feminino , Lateralidade Funcional/fisiologia , Humanos , Lobo Parietal/irrigação sanguínea , Lobo Parietal/diagnóstico por imagem , Lobo Parietal/fisiologia , Córtex Pré-Frontal/irrigação sanguínea , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/fisiologia , Fluxo Sanguíneo Regional/fisiologiaRESUMO
OBJECTIVE: Little has been understood regarding the frequency of eating disorders in Japan. This study was designed to identify the prevalence of anorexia nervosa (AN) and bulimia nervosa (BN) in Japan. METHOD: We asked doctors in all of the relevant medical facilities (130 hospitals and 1,326 clinics) in Niigata Prefecture to report patients with DSM-IV-diagnosed eating disorders who appeared or were admitted between 20-24 October 1997. The response rate was 94.4%. RESULTS: The estimated point prevalences of AN and BN were 4.79 and 1.02, respectively, per 100,000 females. Specifically for the age group of 15-29 years, the prevalence of AN was 17.10 and that of BN 5.79. DISCUSSION: The prevalence of AN and BN in Japan is lower than that for European Caucasian populations. This result may be due to cultural and ethnic differences and/or it may be a transient phenomenon.
Assuntos
Anorexia Nervosa/epidemiologia , Bulimia/epidemiologia , Adolescente , Adulto , Criança , Características Culturais , Feminino , Humanos , Japão/epidemiologia , Pessoa de Meia-Idade , PrevalênciaRESUMO
Four steroidal alkaloids, epipachysamines B (1) and E (2), pachystermine A (3) and pachysamine E (4), were isolated as cytotoxic principles from the MeOH extract of the stems of Pachysandra terminalis SIEB. et ZUCC. (Buxaceae). These alkaloids showed cytotoxic activity against P388 and P388/ADR leukemia cells in vitro. Three of the alkaloids (1-3) were previously isolated from this plant material, and this is the first report of their cytotoxic activity. Pachysamine E (4) is a new alkaloid.
Assuntos
Alcaloides/isolamento & purificação , Antineoplásicos Fitogênicos/isolamento & purificação , Plantas Medicinais/química , Alcaloides/química , Alcaloides/farmacologia , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Japão , Leucemia P388/tratamento farmacológico , Espectroscopia de Ressonância Magnética , Extratos Vegetais , Caules de Planta/química , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta , Células Tumorais CultivadasRESUMO
We investigated psychosocial and clinical factors related to work resumption, delay in returning to work and level of work activity after an acute myocardial infarction in Japanese male patients. A total of 111 married male patients experiencing a first acute myocardial infarction, aged less than 66 years and in full-time employment participated. Interviews and questionnaires were administered during hospitalization to assess potential predictors of work-related outcomes, with follow-up (81.6%) after an average of 8 months. We found that failure to return to work was predicated independently by older age (P=0.019), an introverted personality (P=0.011) and the presence of depressive symptoms during hospitalization (P=0.031). Delay in returning to work was predicted by greater concerns about health (P=0.011), low social support (P=0.021), and a failure to recognise a link between stress, coping style and illness (P=0.001). Resuming work at a lower activity level than before infarction was associated with older age (P=0.008), higher health concerns (P=0.012), and patients' predictions of their lower work activity (P=0.001). Clinical indices of infarction size and disease severity did not predict work-related outcomes. We conclude that psychosocial factors are associated with work resumption in Japanese men characterised by a job-centred lifestyle, with different factors being important for different work outcomes. The psychosocial factors found to be important are similar to those identified in Western societies.
Assuntos
Infarto do Miocárdio/reabilitação , Trabalho/psicologia , Fatores Etários , Idoso , Depressão , Humanos , Japão , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Infarto do Miocárdio/psicologia , Personalidade , Valor Preditivo dos Testes , Apoio Social , Fatores SocioeconômicosRESUMO
Gamma-mangostin, purified from the fruit hull of the medicinal plant Garcinia mangostana caused a parallel rightwards shift of the concentration/response curve for the contraction elicited by 5-hydroxytryptamine (5-HT) in the rabbit aorta (pA2 = 8.2) without affecting the contractile responses to KCl, phenylephrine (alpha1) or histamine (H1). The perfusion pressure response of rat coronary artery to 5-HT (5-HT2A) was reduced concentration dependently by gamma-mangostin (IC50 = 0.32 microM). 5-HT amplified, ADP-induced aggregation of rabbit platelets (5-HT2A) was inhibited by gamma-mangostin (IC50 = 0.29 microM), whereas that induced by thrombin was not affected, nor did gamma-mangostin affect 5-HT-induced contraction of the guinea-pig ileum (5-HT3)in the presence of 5-HT1, 5-HT2 and 5-HT4 receptor antagonists. Furthermore, 5-HT-induced contraction of the rat fundus (5-HT2B) and 5-HT-induced relaxation of the rabbit aorta in the presence of ketanserin (5-HT1) and carbachol-induced contraction of the guinea-pig ileum (muscarinic M3) were not affected by gamma-mangostin (5 microM). Gamma-mangostin inhibited [3H]spiperone binding to cultured rat aortic myocytes (IC50 = 3.5 nM). The Kd for [3H]spiperone binding was increased by gamma-mangostin (3 nM) from 11.7 to 27.4 nM without affecting Bmax. These results suggest that gamma-mangostin is a novel competitive antagonist, free from a nitrogen atom, for the 5-HT2A receptors in vascular smooth muscles and platelets.
Assuntos
Inibidores da Protease de HIV/farmacologia , Músculo Liso Vascular/efeitos dos fármacos , Inibidores da Agregação Plaquetária/farmacologia , Receptores de Serotonina/efeitos dos fármacos , Antagonistas da Serotonina/farmacologia , Xantenos/farmacologia , Xantonas , Animais , Ligação Competitiva , Relação Dose-Resposta a Droga , Cobaias , Técnicas In Vitro , Masculino , Contração Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Perfusão , Extratos Vegetais/farmacologia , Coelhos , Ratos , Ratos Wistar , Receptor 5-HT2A de Serotonina , Receptores de Serotonina/metabolismo , Espiperona/metabolismoRESUMO
Four stereoisomers of 2-amino-3-(1,2-dicarboxyethylthio) propanoic acid were prepared by reaction of L- and D-cysteine with fumaric acid. The absolute configuration of the diastereoisomer of 2-amino-3-(1,2-dicarboxyethylthio) propanoic acid from Amanita pantherina were assigned as (2R, 1'R) and (2R, 1'S) by analysis of the optical properties. Pharmacological tests showed that all of the four stereoisomers inhibited the depolarization of NMDA on spinal motorneurones in newborn rats, The inhibition intensity of L-A, D-A and D-B were higher than that of L-B.
Assuntos
Amanita/química , Cisteína/análogos & derivados , Cisteína/química , Animais , Animais Recém-Nascidos , Cisteína/isolamento & purificação , Cisteína/farmacologia , Conformação Molecular , Neurônios Motores/fisiologia , Ratos , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Medula Espinal/citologia , EstereoisomerismoRESUMO
Hydroxyamino analogues of gamma-aminobutyric acid (GABA) were synthesized and evaluated for inhibitory activity toward gamma-aminobutyric acid aminotransferase (GABA-T). The title compound, 3-(hydroxyamino)propylamine (HPA), showed a potent inhibitory activity. The inhibition is competitive with respect to GABA and the Ki value of GABA-T for HPA is 0.4 mmol. The activity of inhibition is comparable to those of aminoxyacetic acid and valproic acid. 3-(Hydroxyaminomethyl)piperidine (3HMP), a cyclic analogue of HPA, also showed a potent inhibitory activity, whereas 3-(methoxyamino)propylamine (OMe-HPA), 3-(N-hydroxy-N-methylamino)propylamine (NMe-HPA) and 4-(hydroxyamino)piperidine (4HP) showed weak activity.
Assuntos
4-Aminobutirato Transaminase/antagonistas & inibidores , Diaminas/farmacologia , Propilaminas/farmacologia , 4-Aminobutirato Transaminase/síntese química , Aminobutiratos/farmacologia , Ácido Amino-Oxiacético/farmacologia , Diaminas/síntese química , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacologia , Propilaminas/síntese química , Ácido Valproico/farmacologiaRESUMO
The purpose of this study is visual evaluation of the distribution of I-123 iomazenil in the brains of patients with various types of mental disorder and to examine whether chronic administration of a clinical dose of benzodiazepine (BZ) affects the binding of I-123 iomazenil to BZ receptors (BZR). The subjects were 10 patients with mental disorders (3 males and 7 females) with a mean age of 26.8 yrs (range 19-39 yrs). Four of 10 patients were administered BZ for over 3 months and the other six were free of BZ for over one month. The SPECT images were obtained at 5-25 min (early) and 170-190 min (delayed), after the bolus i.v. injection of 167 MBq of I-123 iomazenil, with a triple-head gamma camera. The images were visually evaluated and the washout ratios of each region were calculated. In visual analysis, abnormalities were recognized in 5 patients on the delaye SPECT. The abnormalities were recognized more frequently in the superior frontal lobe. The washout ratio was higher in the BZ (+) patient group than in the BZ (-) patient group. I-123 iomazenil is useful, because the SPECT image with I-123 iomazenil reflects the distribution of BZR on the brain and provides the different information from that obtained with perfusion SPECT, X-ray CT or MRI. The rapid washout of I-123 iomazenil from the brains of BZ (+) patients suggests that chronic administration of a clinical dose of BZ affects the binding of I-123 iomazenil to BZR.
Assuntos
Transtornos de Ansiedade/metabolismo , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Flumazenil/análogos & derivados , Radioisótopos do Iodo , Transtornos Mentais/metabolismo , Compostos Radiofarmacêuticos , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Adulto , Ansiolíticos/uso terapêutico , Transtornos de Ansiedade/diagnóstico por imagem , Transtornos de Ansiedade/tratamento farmacológico , Encéfalo/efeitos dos fármacos , Feminino , Flumazenil/farmacocinética , Humanos , Radioisótopos do Iodo/farmacocinética , Masculino , Transtornos Mentais/diagnóstico por imagem , Transtornos Mentais/tratamento farmacológico , Compostos Radiofarmacêuticos/farmacocinéticaRESUMO
A crude methanolic extract of the fruit hull of Garcinia mangostana L. inhibited the contraction of the isolated rabbit aorta induced by histamine and serotonin. The extract has been fractionated by silica gel chromatography, monitoring the pharmacological activity to give active compounds. On the basis of physicochemical data, the active substances were identified as alpha-mangostin and gamma-mangostin. To define the pharmacological properties of alpha-mangostin, the effect of alpha-mangostin on both histamine H1 and H2 receptors were examined by monitoring the mechanical responses of smooth muscles and measuring the radioligand binding to cultured vascular smooth muscle cells. The results suggest that alpha-mangostin acts as a selective and competitive histamine H1 receptor antagonist. The pharmacological actions of gamma-mangostin on 5-HT receptors were also investigated by using contractile response of vascular smooth muscle, platelet aggregation and radioligand binding studies. The results provide the evidence that gamma-mangostin is a selective and competitive 5-HT2A receptor antagonist. It is of great interest that the structures of alpha-mangostin and gamma-mangostin free from nitrogen atom are not resemble to the common structures of histamine and serotonin receptor antagonists. alpha-Mangostin and gamma-mangostin may become novel types of lead compounds for histamine and serotonin receptor antagonists.
Assuntos
Antagonistas dos Receptores Histamínicos H1/farmacologia , Antagonistas dos Receptores H2 da Histamina/farmacologia , Plantas Medicinais/química , Antagonistas da Serotonina/farmacologia , Xantenos/farmacologia , Xantonas , Animais , Cricetinae , Técnicas In Vitro , Coelhos , Ratos , Xantenos/químicaAssuntos
Ácido Azetidinocarboxílico/análogos & derivados , Gelatinases/antagonistas & inibidores , Inibidores de Metaloproteinases de Matriz , Inibidores de Proteases/farmacologia , Ácido Azetidinocarboxílico/química , Ácido Azetidinocarboxílico/isolamento & purificação , Ácido Azetidinocarboxílico/farmacologia , Metaloproteinase 2 da Matriz , Metaloproteinase 9 da Matriz , Metaloendopeptidases/antagonistas & inibidores , Inibidores de Proteases/química , Inibidores de Proteases/isolamento & purificaçãoRESUMO
In the isolated rabbit thoracic aorta and guinea-pig trachea, alpha-mangostin inhibited histamine-induced contractions in a concentration-dependent manner in the presence or absence of cimetidine, a histamine H2 receptor antagonist. But KCl-, phenylephrine- or carbachol-induced contractions were not affected by alpha-mangostin. The concentration-contractile response curve for histamine was shifted to the right in a parallel manner by alpha-mangostin. In the presence of chlorpheniramine, a histamine H1 receptor antagonist, alpha-mangostin did not affect the relaxation of the rabbit aorta induced by histamine. In the guinea-pig trachea, alpha-mangostin had no effect on the relaxation induced by dimaprit, a histamine H2 receptor agonist. alpha-Mangostin caused a concentration-dependent inhibition of the binding of [3H]mepyramine, a specific histamine H1 receptor antagonist to rat aortic smooth muscle cells. Kinetic analysis of [3H]mepyramine binding indicated the competitive inhibition by alpha-mangostin. These results suggest that alpha-mangostin is a novel competitive histamine H1 receptor antagonist in smooth muscle cells.
Assuntos
Antagonistas dos Receptores Histamínicos H1/farmacologia , Receptores Histamínicos H2/fisiologia , Vasoconstrição/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos , Xantenos/farmacologia , Xantonas , Animais , Aorta Torácica/efeitos dos fármacos , Aorta Torácica/metabolismo , Fenômenos Biomecânicos , Células Cultivadas , Cobaias , Técnicas In Vitro , Modelos Logísticos , Masculino , Músculo Liso/efeitos dos fármacos , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Pirilamina/metabolismo , Coelhos , Ensaio Radioligante , Ratos , Ratos WistarRESUMO
A crude methanolic extract of the fruit hull of Mangosteen, Garcinia mangostana L. inhibited the contractions of isolated thoracic rabbit aorta induced by histamine and serotonin. The extract of the fruit hull has been fractionated by silica gel chromatography, monitoring the pharmacological activity to give alpha- and gamma-mangostin. On the basis of pharmacological data, it is suggested that alpha-mangostin and gamma-mangostin are a histaminergic and a serotonergic receptor blocking agent, respectively.
Assuntos
Antagonistas dos Receptores Histamínicos/isolamento & purificação , Músculo Liso Vascular/fisiologia , Plantas Medicinais , Antagonistas da Serotonina/isolamento & purificação , Xantenos/isolamento & purificação , Xantonas , Animais , Aorta Torácica/efeitos dos fármacos , Aorta Torácica/fisiologia , Ásia , Antagonistas dos Receptores Histamínicos/química , Antagonistas dos Receptores Histamínicos/farmacologia , Técnicas In Vitro , Estrutura Molecular , Contração Muscular/efeitos dos fármacos , Músculo Liso Vascular/efeitos dos fármacos , Coelhos , Antagonistas da Serotonina/química , Antagonistas da Serotonina/farmacologia , Árvores , Xantenos/química , Xantenos/farmacologiaRESUMO
alpha-Mangostin, the principal ingredient of the fruit hull of Garcinia mangostana, caused a concentration-dependent decrease in the activities of both Ca(2+)-ATPase and Ca(2+)-transport of the sarcoplasmic reticulum from rabbit skeletal muscle with an IC50 value of 5 microM. Neither Ca2+ release nor other enzyme activities were affected by alpha-mangostin. Kinetic analysis of the inhibitory effects of alpha-mangostin on Ca(2+)-ATPase suggests that the inhibition of the ATPase is a noncompetitive-type with respect to ATP or Ca2+. alpha-Mangostin may become a useful pharmacological tool for clarifying the physiological functions of Ca(2+)-pumping ATPase and sarcoplasmic reticulum.