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2.
Scand J Immunol ; 83(2): 139-50, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26678711

RESUMO

The identification and specific functions of Kupffer cells (KCs), a liver resident macrophage subpopulation, are still unclear. We compared KCs with peritoneal macrophages using cDNA microarray analysis and found that these cells share some antigens with endothelial cells. KCs highly express VCAM-1 and VEGF receptors (VEGF-Rs) at transcriptional and protein levels. VCAM-1 mediates the functional binding of KCs with lymphocytes and induces KC activation. Among the VEGF receptors, VEGF-R2 and VEGF-R3 were expressed on the KCs, while VEGF-R1 was expressed on other tissue macrophage subsets. VEGF120, a ligand of both VEGF-R1 and VEGF-R2, transduced strong survival and chemotactic signals through the KCs, when compared to PIGF, a VEGF-R1 ligand, indicating that VEGF-R2 plays significant roles in regulating KC activities. Expression of the VEGF-Rs was regulated by TLR4 signalling. These results suggest that the function of KCs is partly regulated by the common antigens shared with endothelial cells.


Assuntos
Antígenos/metabolismo , Células Endoteliais/imunologia , Células de Kupffer/imunologia , Animais , Antígenos/genética , Feminino , Perfilação da Expressão Gênica , Macrófagos Peritoneais/imunologia , Camundongos , Camundongos Endogâmicos C57BL , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de Fatores de Crescimento do Endotélio Vascular/genética , Receptores de Fatores de Crescimento do Endotélio Vascular/metabolismo , Transdução de Sinais/imunologia , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo , Molécula 1 de Adesão de Célula Vascular/genética , Molécula 1 de Adesão de Célula Vascular/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Cicatrização/genética , Cicatrização/imunologia
3.
Br J Pharmacol ; 170(2): 341-51, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23763343

RESUMO

BACKGROUND AND PURPOSE: Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder with no effective treatment. Fasudil hydrochloride (fasudil), a potent rho kinase (ROCK) inhibitor, is useful for the treatment of ischaemic diseases. In previous reports, fasudil improved pathology in mouse models of Alzheimer's disease and spinal muscular atrophy, but there is no evidence in that it can affect ALS. We therefore investigated its effects on experimental models of ALS. EXPERIMENTAL APPROACH: In mice motor neuron (NSC34) cells, the neuroprotective effect of hydroxyfasudil (M3), an active metabolite of fasudil, and its mechanism were evaluated. Moreover, the effects of fasudil, 30 and 100 mg·kg(-1), administered via drinking water to mutant superoxide dismutase 1 (SOD1(G93A)) mice were tested by measuring motor performance, survival time and histological changes, and its mechanism investigated. KEY RESULTS: M3 prevented motor neuron cell death induced by SOD1(G93A). Furthermore, M3 suppressed both the increase in ROCK activity and phosphorylated phosphatase and tensin homologue deleted on chromosome 10 (PTEN), and the reduction in phosphorylated Akt induced by SOD1(G93A). These effects of M3 were attenuated by treatment with a PI3K inhibitor (LY294002). Moreover, fasudil slowed disease progression, increased survival time and reduced motor neuron loss, in SOD1(G93A) mice. Fasudil also attenuated the increase in ROCK activity and PTEN, and the reduction in Akt in SOD1(G93A) mice. CONCLUSIONS AND IMPLICATIONS: These findings indicate that fasudil may be effective at suppressing motor neuron degeneration and symptom progression in ALS. Hence, fasudil may have potential as a therapeutic agent for ALS treatment.


Assuntos
1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/análogos & derivados , Esclerose Lateral Amiotrófica/tratamento farmacológico , Neurônios Motores/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/administração & dosagem , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/farmacologia , Esclerose Lateral Amiotrófica/fisiopatologia , Animais , Modelos Animais de Doenças , Progressão da Doença , Relação Dose-Resposta a Droga , Masculino , Camundongos Transgênicos , Neurônios Motores/patologia , Fármacos Neuroprotetores/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação/efeitos dos fármacos , Inibidores de Proteínas Quinases/administração & dosagem , Proteínas Proto-Oncogênicas c-akt/metabolismo , Superóxido Dismutase/genética , Superóxido Dismutase-1 , Taxa de Sobrevida , Quinases Associadas a rho/antagonistas & inibidores
5.
J Gastroenterol Hepatol ; 16(7): 723-8, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11446878

RESUMO

BACKGROUND AND AIM: The genetic polymorphism of cytochrome P450 (CYP) 2C19 has been shown to influence the efficacy of Helicobacter pylori eradication therapy with a proton pump inhibitor (PPI) and amoxicillin (so-called dual therapy). Omeprazole, a widely used PPI, and rabeprazole, a new PPI, are metabolized in different pathways in terms of CYP2C19 genetic polymorphisms. In this study, we compared the efficacy of omeprazole and rabeprazole in a 2-week dual therapy in relation to CYP2C19 polymorphism. METHODS: One hundred and ninety-nine patients with peptic ulcer disease were randomly assigned to receive one of the following regimens: 500 mg t.i.d. amoxicillin together with either 20 mg b.i.d. omeprazole or 10 mg b.i.d rabeprazole. The eradication of H. pylori was evaluated by using a bacterial culture and a [(13)C]-urea breath test at 1--2 months after completion of treatment. Cytochrome P4502C19 polymorphism was analyzed by using polymerase chain reaction-restriction fragment length polymorphism. RESULTS: Intention-to-treat-based cure rates for the omeprazole or rabeprazole regimens were 66.3% (95% CI, 56--75) and 62.4% (95% CI, 52--71), respectively, without significant difference. Cytochrome P4502C19 genetic polymorphism did not influence the cure rates in either of these regimens. We analyzed various factors associated with treatment failure (PPI, CYP2C19 genotype, and smoking habit) by using multiple logistic regression; smoking was the only significant independent factor for treatment failure. CONCLUSION: Omeprazole and rabeprazole were equally effective in combination with amoxicillin in eradicating H. pylori, irrespective of the PPI used (omeprazole or rabeprazole) and CYP2C19 genetic polymorphism. Smoking significantly decreased the cure rate of H. pylori infection in the dual therapy.


Assuntos
Amoxicilina/uso terapêutico , Antiulcerosos/uso terapêutico , Benzimidazóis/uso terapêutico , Sistema Enzimático do Citocromo P-450/genética , Inibidores Enzimáticos/uso terapêutico , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori/genética , Omeprazol/uso terapêutico , Inibidores da Bomba de Prótons , 2-Piridinilmetilsulfinilbenzimidazóis , Adulto , Idoso , Amoxicilina/administração & dosagem , Antiulcerosos/administração & dosagem , Benzimidazóis/administração & dosagem , Inibidores Enzimáticos/administração & dosagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Omeprazol/administração & dosagem , Úlcera Péptica/tratamento farmacológico , Polimorfismo Genético , Rabeprazol , Resultado do Tratamento
6.
Jpn J Cancer Res ; 92(6): 680-7, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11429058

RESUMO

A novel reagent, FTY720 (2-amino-2-[2-(4-octylphenyl)ethyl]-1,3-propanediol hydrochloride), has been shown to induce a significant decrease of lymphocytes and lymphoma cells and is expected to be a potent immunosuppressant and anti-tumor drug. The decrease in lymphocytes and lymphoma cells is mainly the result of FTY720-induced apoptosis. FTY720 directly affects mitochondria and induces cell death. Moreover, FTY720 activates protein phosphatase (PP) 2A and affects anti-apoptotic intracellular signal transduction proteins to attenuate the anti-apoptotic effect. In this study, we examined the relationship between FTY720-induced apoptosis and cell cycle regulation. FTY720 induced apoptosis significantly at the G0 / G1 phase and caused G0 / G1 cell cycle arrest of the human lymphoma cell lines HL-60RG and Jurkat. Simultaneously, retinoblastoma protein (pRB) was dephosphorylated, suggesting that dephosphorylation of pRB was related to FTY720-induced G0 / G1 cell cycle arrest. Because this dephosphorylation was completely blocked by a specific PP1 / 2A inhibitor, okadaic acid, it appears that FTY720-activated PP2A is essential for FTY720-induced cell cycle arrest. FTY720-induced apoptosis was inhibited by Bcl-2 overexpression in Jurkat cells, but this did not prevent FTY720-induced cell cycle arrest, suggesting that the mechanism of FTY720-induced cell cycle arrest is independent of the mechanism of FTY720-induced apoptosis. These two independent pathways strengthen the effect of FTY720.


Assuntos
Antineoplásicos/farmacologia , Apoptose , Ciclo Celular , Imunossupressores/farmacologia , Propilenoglicóis/farmacologia , Western Blotting , Bromodesoxiuridina/metabolismo , Ciclo Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Fragmentação do DNA/efeitos dos fármacos , Regulação para Baixo , Ativação Enzimática , Cloridrato de Fingolimode , Células HL-60 , Humanos , Células Jurkat , Ácido Okadáico/farmacologia , Fosfoproteínas Fosfatases/metabolismo , Fosforilação , Testes de Precipitina , Proteína do Retinoblastoma/metabolismo , Transdução de Sinais , Esfingosina/análogos & derivados , Fatores de Tempo
7.
J Immunol ; 165(6): 3250-9, 2000 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-10975841

RESUMO

FTY720 has immunosuppressive activity in experimental organ transplantation and shows a prompt and protracted decrease of blood T lymphocytes upon oral administration. The blood lymphocyte decrease in vivo was mainly a result of FTY720-induced apoptosis. However, this apoptotic mechanism is not well understood. We examined the mechanism of FTY720-induced apoptosis in lymphoma. Western blotting and fluorescent caspase-specific substrate revealed that caspase-3 is involved in FTY720-induced apoptosis, whereas caspase-1 is not. Apoptotic cell death was inhibited by the pan-caspase inhibitor, Z-VAD-FMK, suggesting that caspase activation is essential for FTY720-induced apoptosis. FTY720 reduced mitochondrial transmembrane potential and released cytochrome c from the mitochondria of intact cells as well as in a cell-free system even in the presence of Z-VAD-FMK. As these mitochondrial reactions occurred before caspase activation, we concluded that FTY720 directly influences mitochondrial functions. The inhibition of mitochondrial permeability transition by Bcl-2 overexpression or by chemical inhibitors prevented all apoptotic events occurring in intact cells and in a cell-free system. Moreover, using a cell-free system, FTY720 did not directly affect isolated nuclei or cytosol. These results indicate that FTY720 directly affects mitochondria and triggers permeability transition to induce further apoptotic events.


Assuntos
Apoptose/efeitos dos fármacos , Grupo dos Citocromos c/metabolismo , Imunossupressores/farmacologia , Membranas Intracelulares/enzimologia , Mitocôndrias/enzimologia , Propilenoglicóis/farmacologia , Apoptose/imunologia , Caspase 3 , Caspases/metabolismo , Núcleo Celular/efeitos dos fármacos , Grupo dos Citocromos c/antagonistas & inibidores , Citosol/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Ativação Enzimática/imunologia , Cloridrato de Fingolimode , Células HL-60 , Humanos , Membranas Intracelulares/efeitos dos fármacos , Membranas Intracelulares/metabolismo , Células Jurkat , Potenciais da Membrana/efeitos dos fármacos , Potenciais da Membrana/imunologia , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Permeabilidade/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/fisiologia , Esfingosina/análogos & derivados
8.
Immunopharmacology ; 48(1): 75-85, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10822091

RESUMO

The immunosuppressant FTY720 induces a drastic decrease in blood lymphocytes, especially T cells; a decrease which is assumed to be the immunosuppressive mechanism of this drug. FTY720 causes cell death in vitro in lymphocytes and leukemia cells. However, the deletion mechanism of blood lymphocytes in vivo remains unclear. We investigated whether administration of FTY720 induced lymphocyte apoptosis in blood circulation. A marked decrease in the number of blood lymphocytes was observed within an hour after a single oral administration of FTY720 at doses of 5-10 mg/kg in rats and mice. Experiments using fluorescein isothiocyanate (FITC)-Annexin V and APO-BRDU methods revealed that FTY720 induced blood lymphocyte apoptosis in a dose-dependent manner. On the other hand, lymphocyte homing to Peyer's patches was proposed as the mechanism underlying the blood lymphocyte decrease at these doses. However, similar results were obtained when using aly/aly mice, which lack Peyer's patches and lymph nodes. Thus, we concluded that apoptosis of blood lymphocytes was induced immediately after administration of FTY720, and the cells could be immediately scavenged by phagocytes or the reticuloendothelial system in addition to Peyer's patches homing. We also concluded that T cells were highly sensitive to FTY720, which induced apoptosis in vivo.


Assuntos
Apoptose , Imunossupressores/farmacologia , Propilenoglicóis/farmacologia , Linfócitos T/efeitos dos fármacos , Administração Oral , Animais , Anexina A5 , Linfócitos B/efeitos dos fármacos , Separação Celular , Relação Dose-Resposta a Droga , Regulação para Baixo , Cloridrato de Fingolimode , Fluoresceína-5-Isotiocianato , Granulócitos/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Monócitos/efeitos dos fármacos , Ratos , Ratos Endogâmicos Lew , Esfingosina/análogos & derivados , Linfócitos T/citologia
9.
FEBS Lett ; 410(2-3): 131-5, 1997 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-9237615

RESUMO

KW-2228 is a tailored human granulocyte colony-stimulating factor (hG-CSF) which has more potent granulopoietic activity and is more stable than wild-type hG-CSF. Analysis of the 2.3 A resolution crystal structure of KW-2228 unambiguously revealed a four-alpha-helix bundle motif with up-up-down-down connectivity. The structures of long overhand loops connecting the helices and the N-terminus have been definitively determined. The present analysis has clearly revealed that substituted residues play important roles in fastening a long overhand loop to the N- and C-termini to fix the conformation. This conformation should be responsible for a substantial enhancement of the biological activity and stability.


Assuntos
Fator Estimulador de Colônias de Granulócitos/química , Cristalografia por Raios X , Dissulfetos , Fator Estimulador de Colônias de Granulócitos/farmacologia , Humanos , Modelos Moleculares , Estrutura Secundária de Proteína , Relação Estrutura-Atividade
10.
J Med Chem ; 38(15): 2887-92, 1995 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-7636849

RESUMO

A series of (E)-4-(2-[[3-(indol-5-yl)-1-oxo-2-butenyl]amino]phenoxy)butyric acid derivatives was prepared, and the derivatives were demonstrated to be potent inhibitors of steroid 5 alpha-reductase in the rat prostate. The structure-activity relationships were as follows. An alpha-branched alkyl or benzyl substituent of proper size at position 1 of the indole is crucial for optimal enzyme inhibitory activity. N-Methylation of the amide NH resulted in complete loss of activity. Thus, coplanarity of the benzene ring and amide moiety is essential for such activity. Among the compounds prepared, (E)-4-(2-[[3-[1-[bis(4-fluorophenyl)methyl]indol-5-yl]-1-oxo-2- butenyl]-amino]phenoxy)butyric acid (57, KF18678) was one of the most potent compounds (rat prostate 5 alpha-reductase IC50 = 3.3 nM).


Assuntos
Inibidores de 5-alfa Redutase , Butiratos/síntese química , Butiratos/farmacologia , Indóis/síntese química , Indóis/farmacologia , Próstata/química , Próstata/efeitos dos fármacos , Animais , Butiratos/química , Cristalografia por Raios X , Indóis/química , Masculino , Conformação Molecular , Estrutura Molecular , Ratos , Ratos Wistar , Relação Estrutura-Atividade
11.
J Thorac Imaging ; 9(2): 112-5, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-8207775

RESUMO

The technique of inflation and fixation of the lung with polyethylene glycol is useful for specimen radiography and radiologic-pathologic correlation, but it is limited by poor histologic staining of the fixed tissue. To improve staining we used formalin to distend and fix the lung before standard fixation with a polyethylene glycol mixture. In this preliminary study, canine and infant lungs, and lungs from three cases of lung cancer were examined. The modified technique provided high-quality staining and satisfactory specimen radiography in all cases except one of the lung cancers; in this case excessive shrinkage occurred and degraded radiographic quality. We conclude that the new method of preparation permits both specimen radiography and high quality staining of the fixed tissue.


Assuntos
Pulmão/diagnóstico por imagem , Pulmão/patologia , Fixação de Tecidos , Adulto , Animais , Cães , Formaldeído , Humanos , Imuno-Histoquímica , Lactente , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/patologia , Polietilenoglicóis , Tomografia Computadorizada por Raios X
12.
J Mol Biol ; 214(1): 25-6, 1990 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-1695250

RESUMO

Human granulocyte colony-stimulating factor (hG-CSF) specifically stimulates proliferation of neutrophils. Two crystal forms of a mutant of hG-CSF expressed in Escherichia coli have been obtained using the hanging drop vapour diffusion method. One form is triclinic, space group P1, with cell dimensions a = 37.3 A, b = 46.4 A, c = 47.7 A, alpha = 105.5 degrees, beta = 98.0 degrees and gamma = 109.4 degrees. The other is monoclinic, space group C2, with cell dimensions a = 82.0 A, b = 49.2 A, c = 49.4 A and beta = 113.9 degrees. Both crystal forms diffract beyond 2.0 A and are suitable for X-ray analysis.


Assuntos
Fatores Estimuladores de Colônias , Cristalização , Fator Estimulador de Colônias de Granulócitos , Humanos , Conformação Proteica , Proteínas Recombinantes , Relação Estrutura-Atividade , Difração de Raios X
13.
J Mol Biol ; 199(1): 183-93, 1988 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-3351918

RESUMO

The structure of a low-potential [4Fe-4S] ferredoxin from Bacillus thermoproteolyticus has been solved using anomalous scattering data from iron atoms in the diffraction data of native crystals and refined partially to a crystallographic R-factor of 0.33, with 2.3 A (1 A = 0.1 nm) resolution data. The least-squares refinement based on the Bijvoet differences has determined that the four iron atoms in the cluster are an equal distance, approximately 2.8 A, apart. The NH ... S hydrogen bonds between polypeptide nitrogen atoms, and both cysteine and inorganic sulfur atoms, are present, as in ferrodoxin from Peptococcus aerogenes. The polypeptide chain of the B. thermoproteolyticus ferredoxin has a fold closely similar to that of 2[4Fe-4S] ferredoxin from P. aerogenes. The structural correspondence indicates strongly that both types of ferredoxin evolved from a common ancestor. The second cluster-binding region in P. aerogenes ferredoxin corresponds to the alpha-helix in B. thermoproteolyticus ferredoxin. The secondary-structure predictions strongly suggest that the alpha-helix is generally present in the monocluster-type ferredoxins. The conformational change to alpha-helix, insertions of a loop and a protrusion, as well as the absence of the second cluster in B. thermoproteolyticus ferredoxin, result in the lack of 2-fold symmetry present in P. aerogenes ferredoxin. So, the track of gene duplication is no longer detectable in the tertiary structure alone. The evolutionary events that may have occurred in the ferredoxins with the [4Fe-4S] cluster are discussed.


Assuntos
Bacillus/análise , Ferredoxinas , Sequência de Aminoácidos , Evolução Biológica , Cristalografia , Dados de Sequência Molecular , Conformação Proteica
15.
Virology ; 145(1): 191-4, 1985 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18640548

RESUMO

Arabis mosaic virus, a member of the nepovirus group, was purified by a combination of differential centrifugation, gel filtration, and sucrose density gradient techniques. The molecular weight of the coat protein, estimated by SDS-polyacrylamide gel electrophoresis, and consideration of subunit packing indicated the surface lattice of the virion to be T = 1. The virus was stable to treatment with trypsin at neutral pH. The virus crystallizes in the cubic system, space group P2(1)3 with a = 387 A . There are four particles per unit cell, each situated on a crystallographic threefold axis.

17.
Acta Endocrinol (Copenh) ; 108(4): 440-4, 1985 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2986399

RESUMO

For determination of the site of action of oestrogen (E) during the negative and positive feedback phases of gonadotrophin secretions, studies were made on the pituitary response to a small amount of LRH and the pulsatility of gonadotrophins after E administration in normal cycling women in the mid-follicular phase. The pituitary responses to an iv bolus of 2.5 micrograms of synthetic LRH were evaluated by measuring serum LH and FSH 2 h before and 8 h after administration of 20 mg of conjugated E (Premarin). In the next cycle, the pituitary responses to a same dose of LHRH were also observed 2 h before and 56 h after E injection. The mean levels of serum LH and FSH and the peak responses to LRH were significantly (P less than 0.05) decreased 8 h after E injection, but were significantly (P less than 0.05) increased 56 h after E administration. In the third cycle, the pulsatility of gonadotrophins was evaluated by measuring serum LH and FSH every 15 min for 180 min before and 8 h and 56 h after E injection. The pulse frequencies of gonadotrophins were not significantly different before and 8 h and 56 h after E injection. The amplitudes of pulses 56 h after Premarin injection were significantly higher than those before the injection. These findings suggest that the negative and positive feedback effects of E on gonadotrophin secretion may be caused, in part, by its direct action on the pituitary response to LRH.


Assuntos
Estrogênios Conjugados (USP)/farmacologia , Hormônio Foliculoestimulante/metabolismo , Hormônio Luteinizante/metabolismo , Adulto , Retroalimentação , Feminino , Hormônio Foliculoestimulante/sangue , Fase Folicular , Hormônio Liberador de Gonadotropina/farmacologia , Humanos , Hormônio Luteinizante/sangue
18.
Endocrinol Jpn ; 31(5): 529-32, 1984 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-6097441

RESUMO

We have reported that iv administration of conjugated estrogens results in no significant change in the plasma LH-RH level during the negative feedback phase of LH, suggesting that estrogen does not suppress LH by decreasing hypothalamic LH-RH. To determine the site of estrogen action during the negative feedback phase, we studied the pituitary response to a small amount of LH-RH after estrogen administration in normal cyclic women in the mid-follicular phase. The pituitary responses to an iv bolus of 2.5 micrograms of synthetic LH-RH were evaluated by measuring serum LH and FSH 2 h before and 8 h after administration of 20 mg of conjugated estrogens (Premarin). The mean levels of serum LH and FSH were significantly (p less than 0.05) decreased 8 h after the injection. The peak responses of LH and FSH to LH-RH were also significantly (p less than 0.05) reduced after Premarin administration. These findings suggest that the negative feedback effect of estrogen on gonadotropin secretion is caused by its direct suppression on the pituitary response to LH-RH.


Assuntos
Estrogênios Conjugados (USP)/farmacologia , Hormônio Foliculoestimulante/sangue , Hormônio Luteinizante/sangue , Adulto , Retroalimentação , Feminino , Hormônio Liberador de Gonadotropina/metabolismo , Hormônio Liberador de Gonadotropina/farmacologia , Hormônio Liberador de Gonadotropina/fisiologia , Humanos , Radioimunoensaio
19.
Acta Endocrinol (Copenh) ; 107(2): 145-8, 1984 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-6388205

RESUMO

The effect of hydrocortisone on the release of luteinizing hormone (LH) and LH-releasing hormone (LRH) in response to clomiphene citrate (clomiphene) were examined in a sequential double chamber perifusion system by perifusing the mediobasal hypothalami (MBH) and/or pituitaries excised from normal female rats in dioestrus. When the MBH and the pituitary were perifused in sequence with medium containing 5 X 10(-6) M hydrocortisone, a significant release in LH (100- 150% increase, P less than 0.01-P less than 0.05) was observed 40 min after the administration of 3 X 10(-8) mol clomiphene. Clomiphene had no effect on LH release from the pituitary when perifused in series with the MBH without basal hydrocortisone infusion. Administration of clomiphene did not cause a significant increase in LH from the pituitary perifused alone, with or without medium containing hydrocortisone. The concentration of LRH in the efflux was significantly increased 40 min after clomiphene administration when MBH was perifused with medium containing hydrocortisone, whereas clomiphene had no effect when perifused with medium only. These data indicate that hydrocortisone stimulates the effect of clomiphene on LRH release from the hypothalamus, which in turn induces LH release from the pituitary.


Assuntos
Clomifeno/farmacologia , Hormônio Liberador de Gonadotropina/metabolismo , Hidrocortisona/farmacologia , Animais , Diestro/efeitos dos fármacos , Sinergismo Farmacológico , Feminino , Hipotálamo Médio/efeitos dos fármacos , Técnicas In Vitro , Hormônio Luteinizante/metabolismo , Perfusão , Hipófise/efeitos dos fármacos , Gravidez , Ratos , Ratos Endogâmicos
20.
Int J Gynaecol Obstet ; 21(6): 435-8, 1983 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-6141103

RESUMO

Real-time ultrasonic scanning was performed in 21 infertile Japanese women during 37 menstrual cycles. The maximum diameter prior to ovulation was 23.3 +/- 2.9 mm in spontaneous ovulation cycles, 29.6 +/- 5.2 mm in case of clomiphene therapies, and 26.7 +/- 3.9 mm in HMG-HCG therapies, respectively. Size of the graafian follicles was maximum at almost the same time as the LH peak in the plasma and urine, respectively. The LH peak in the urine was determined by the hemagglutination inhibition assay, the results of which were obtainable within 2 h. Four patients became pregnant (19.0%). There was no statistical correlation between the diameter of the largest follicle and the plasma estradiols (r = 0.28, 0.2 less than P less than 0.3) or between the diameter of the largest follicle and the peak luteinising hormone level (r = 0.27, 0.3 less than P less than 0.4). Therefore, the combination of the real-time ultrasound and a hemagglutination inhibition assay for LH in urine can be clinically applied to detect the precise day of the ovulation.


Assuntos
Folículo Ovariano/crescimento & desenvolvimento , Ultrassonografia , Feminino , Testes de Inibição da Hemaglutinação , Humanos , Hormônio Luteinizante/urina , Detecção da Ovulação/métodos
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