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1.
Vox Sang ; 108(3): 302-9, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25523606

RESUMO

BACKGROUND AND OBJECTIVES: Previously, a weak phenotype Am or Bm was assumed to be caused by a reduction of A or B gene expression in bone marrow cells, but not in mucus-secreting cells. However, ABO expression has not been examined in erythroid progenitor cells of Am or Bm individuals. MATERIALS AND METHODS: We carried out in vitro erythroid differentiation of CD34(+) cells from peripheral blood of a Bm individual harbouring a 3.0-kb deletion including an erythroid cell-specific regulatory element, named the +5.8-kb site, in intron 1 of the human ABO blood group gene. RESULTS: During the in vitro differentiation of CD34(+) cells from this Bm individual into erythroid cells, B-antigens were not detectable on the cultured cells by flow cytometric analysis, and allele-specific RT-PCR consistently detected the transcripts from the O allele, but not from the B allele. Moreover, chromatin immunoprecipitation assay demonstrated that both RUNX1 and GATA-2 or GATA-1 were bound to the +5.8-kb site in cultured erythroid cells expressing ABO. CONCLUSION: It is likely that the +5.8-kb site enhances transcription from the ABO promoter in erythroid cells through binding of RUNX1 and GATA-2 or GATA-1.


Assuntos
Sistema ABO de Grupos Sanguíneos/genética , Antígenos CD34/metabolismo , Células Eritroides/imunologia , Células Precursoras Eritroides/imunologia , Sistema ABO de Grupos Sanguíneos/metabolismo , Alelos , Antígenos CD34/genética , Células Cultivadas , Células Eritroides/citologia , Células Precursoras Eritroides/citologia , Hematopoese , Humanos , Regiões Promotoras Genéticas
2.
Bone Marrow Transplant ; 38(10): 681-6, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16980988

RESUMO

We determined the alleles of five polymorphic molecules including HA-1 and four adhesion molecules for 106 patients transplanted with HLA-identical stem cell grafts and investigated the association of mismatches as correlates of relapse and graft-versus-host disease (GVHD). All 106 recipients underwent stem cell transplantation (SCT) after myeloablative conditioning between 1985 and 2002. Risk status of disease at SCT was standard (n=63) and high (n=42). After SCT, 36, 49 and 33 developed acute GVHD, chronic GVHD and relapsed, respectively. Our patients relapsed at rates of 16.7 and 38.6% with one or more and without incompatibilities (P=0.013). The relapse rates of patients with CD62L, CD31 codon 563, CD31 codon 125, HA-1 and CD49b incompatibilities were 5.9, 11.8, 15.4, 16.0 and 33.3%, respectively. The frequency of acute GVHD did not differ regardless of incompatibilities. In standard-risk group, the accumulated relapse rates of 19 and 44 patients with and without minor histocompatibility antigen incompatibility were 22% and unexpectedly 66%, respectively (P=0.02). The probability of 12-year survival was 88% in the former and 66% in the latter patients (P=0.03). Our data suggest that incompatibility of CD62L, CD31 codon 563 and CD31 codon 125 contributes to a graft-versus-leukemia effect rather than to GVHD, resulting in prolonged survival after HLA-identical SCT.


Assuntos
Efeito Enxerto vs Leucemia/imunologia , Leucemia/terapia , Antígenos de Histocompatibilidade Menor , Transplante de Células-Tronco , Doença Aguda , Sequência de Bases , Primers do DNA/genética , Feminino , Doença Enxerto-Hospedeiro/imunologia , Antígenos HLA , Humanos , Japão/epidemiologia , Leucemia/imunologia , Leucemia/mortalidade , Masculino , Antígenos de Histocompatibilidade Menor/genética , Recidiva , Taxa de Sobrevida
3.
Cell Death Differ ; 11 Suppl 2: S153-61, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15153943

RESUMO

The tumor suppressor Chk2 kinase plays crucial roles in regulating cell-cycle checkpoints and apoptosis following DNA damage. We investigated the expression levels of the genes encoding Chk2 and several cell-cycle regulators in nine cell lines from lymphoid malignancies, including three Hodgkin's lymphoma (HL) lines. We found that all HL cell lines exhibited a drastic reduction in Chk2 expression without any apparent mutation of the Chk2 gene. However, expression of Chk2 in HL cells was restored following treatment with the histone deacetylase inhibitors trichostatin A (TsA) and sodium butyrate (SB), or with the DNA methyltransferase inhibitor 5-aza-2'-deoxycytidine (5Aza-dC). Chromatin-immunoprecipitation (Chip) assays revealed that treatment of HL cells with TsA, SB or 5Aza-dC resulted in increased levels of acetylated histones H3 and H4, and decreased levels of dimethylated H3 lysine 9 at the Chk2 promoter. These results indicate that expression of the Chk2 gene is downregulated in HL cells via epigenetic mechanisms.


Assuntos
Azacitidina/análogos & derivados , Epigênese Genética/fisiologia , Regulação Neoplásica da Expressão Gênica , Doença de Hodgkin/genética , Linfoma/genética , Proteínas Serina-Treonina Quinases/genética , Acetilação , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Apoptose/efeitos da radiação , Azacitidina/farmacologia , Butiratos/farmacologia , Linhagem Celular Tumoral , Quinase do Ponto de Checagem 2 , Decitabina , Histonas/efeitos dos fármacos , Histonas/metabolismo , Humanos , Ácidos Hidroxâmicos/farmacologia , Metilação , Proteínas Serina-Treonina Quinases/efeitos dos fármacos , RNA Mensageiro/genética
5.
Am J Hematol ; 71(4): 248-55, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12447952

RESUMO

1998, a consensus meeting was held in Miyazaki, Japan, to develop an approach to management of febrile neutropenia (FN). The K-HOT study group decided to examine whether this proposal was applicable to clinical practice in a multicenter study. Patients who developed fever with neutrophil counts <1,000/microL were randomized to receive either a single antibiotic, cefepime or one of the carbapenems, or a combination of cefepime and an aminoglycoside. Patients who became afebrile within the first 3 days were continued on the same treatment. Patients who remained febrile were switched to a combination regimen if they were randomized to receive a single agent, and patients on combination medication were changed from cefepime to another cephalosporin. A total of 165 patients were entered into the trial. One hundred fifty-three patients were evaluable for response. The average age was 52 years, and 70% of the patients had acute leukemia. Severe neutropenia, defined as <100/microL at the time of FN, was seen in 62% of the patients on entry and during the course of treatment 71% of patients experienced neutrophil counts of <100/microL. Microbiologically documented infection was seen in 6.5% for monotherapy, and 10.5% for a combination treatment, and fever of unknown origin occurred in 75.3% and 59.2% of the patients in each regimen, respectively. Excellent to good response was seen in two-thirds of the patients in all treatment groups. Adverse events were minimal, and three early deaths were observed at days 9, 16, and 16 among patients treated with a single antibiotic and three in the combination regimen group at days 14, 15, and 20. These results indicate that cefepime or a carbapenem alone is as effective as a combination of cefepime and an aminoglycoside for treating FN.


Assuntos
Antibacterianos/uso terapêutico , Carbapenêmicos/uso terapêutico , Cefalosporinas/uso terapêutico , Quimioterapia Combinada/uso terapêutico , Febre/etiologia , Neutropenia/tratamento farmacológico , Adulto , Algoritmos , Aminoglicosídeos , Carbapenêmicos/administração & dosagem , Cefepima , Cefalosporinas/administração & dosagem , Esquema de Medicação , Feminino , Humanos , Leucemia/fisiopatologia , Linfoma/fisiopatologia , Masculino , Neutropenia/etiologia
6.
Eur J Haematol ; 67(3): 152-7, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11737247

RESUMO

Chronic lymphocytic leukemia (CLL) is a rare disease in Japan. Recent advances in molecular biology, diagnostic criteria and classification of CLL have reinforced the concept of each category of CLL as a distinct entity. Since there have been no recent studies on the incidence and prevalence of CLL in Japan, the Kyushu Hematology Organization for Treatment (K-HOT) Study Group conducted two studies of CLL. One study is a prospective registration of newly diagnosed hematological disorders, which gave us some idea of the incidence of CLL in our region (Kyushu island) where adult T-cell leukemia is endemic. A total of 677 patients with hematological disorders were registered over a 6-month period and 11 patients were diagnosed as having CLL among 182 leukemia patients. This amounts to 6% of all leukemias, which is twice as frequent as previously reported in Japan. The other study is a retrospective analysis of CLL. Eleven institutions of the K-HOT Group analysed their diagnostic records of chronic lymphoid leukemia, and 145 patients with CLL were found over a period of 3-12 yr. After the data were reviewed 11 patients were excluded through having a different type of leukemia. The proportion of chronic B-cell lymphoid leukemia was 73% (98/134), while that of T-cell leukemia was 18% (24/134). The proportion of T-cell chronic leukemia was 5-6 times higher than that in Western countries. Two institutions had a complete database on hematological disorders. From this database, the annual incidence of CLL was estimated to be 0.48 per 100 000. Thus, the incidence of CLL in Japan is at least 4-5 times lower than that in Western countries, suggesting that chronic B-cell leukemia is really rare, but chronic leukemia of T-cell lineage develops in Japan as frequently as in Western societies. Further investigation is required to delineate why the incidence of B-CLL is so low in Japan.


Assuntos
Leucemia Linfocítica Crônica de Células B/epidemiologia , Leucemia Prolinfocítica de Células T/epidemiologia , Adulto , Idoso , Bases de Dados Factuais , Feminino , Humanos , Incidência , Japão/epidemiologia , Leucemia Linfocítica Crônica de Células B/patologia , Leucemia Prolinfocítica de Células T/patologia , Masculino , Pessoa de Meia-Idade
7.
Br J Pharmacol ; 133(5): 746-54, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11429400

RESUMO

YM471, (Z)-4'-[4,4-difluoro-5-[2-(4-dimethylaminopiperidino)-2-oxoethylidene]-2,3,4,5-tetrahydro-1H-1-benzoazepine-1-carbonyl]-2-phenylbenzanilide monohydrochloride, is a newly synthesized potent vasopressin (AVP) receptor antagonist. Its effects on binding to and signal transduction by cloned human AVP receptors (V(1A), V(1B) and V(2)) stably expressed in Chinese hamster ovary (CHO) cells, and oxytocin receptors in human uterine smooth muscle cells (USMC) were studied. YM471 potently inhibited specific [(3)H]-AVP binding to V(1A) and V(2) receptors with K(i) values of 0.62 nM and 1.19 nM, respectively. In contrast, YM471 exhibited much lower affinity for V(1B) and oxytocin receptors with K(i) values of 16.4 microM and 31.6 nM, respectively. In CHO cells expressing V(1A) receptors, YM471 potently inhibited AVP-induced intracellular Ca(2+) concentration ([Ca(2+)](i)) increase, exhibiting an IC(50) value of 0.56 nM. However, in human USMC expressing oxytocin receptors, YM471 exhibited much lower potency in inhibiting oxytocin-induced [Ca(2+)](i) increase (IC(50)=193 nM), and did not affect AVP-induced [Ca(2+)](i) increase in CHO cells expressing V(1B) receptors. Furthermore, in CHO cells expressing V(2) receptors, YM471 potently inhibited the production of cyclic AMP stimulated by AVP with an IC(50) value of 1.88 nM. In all assays, YM471 showed no agonistic activity. These results demonstrate that YM471 is a potent, nonpeptide human V(1A) and V(2) receptor antagonist which will be a valuable tool in defining the physiologic and pharmacologic actions of AVP.


Assuntos
Antagonistas dos Receptores de Hormônios Antidiuréticos , Azepinas/farmacologia , Músculo Liso/efeitos dos fármacos , Piperidinas/farmacologia , Receptores de Ocitocina/efeitos dos fármacos , Útero/efeitos dos fármacos , Animais , Arginina Vasopressina/metabolismo , Ligação Competitiva/efeitos dos fármacos , Células CHO , Cálcio/metabolismo , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Cricetinae , AMP Cíclico/metabolismo , Relação Dose-Resposta a Droga , Feminino , Humanos , Indóis/farmacologia , Morfolinas/farmacologia , Músculo Liso/citologia , Músculo Liso/metabolismo , Ocitocina/metabolismo , Pirrolidinas/farmacologia , Ensaio Radioligante , Receptores de Ocitocina/metabolismo , Receptores de Vasopressinas/genética , Receptores de Vasopressinas/metabolismo , Compostos de Espiro/farmacologia , Trítio , Útero/metabolismo
8.
Clin Calcium ; 11(12): 1658-63, 2001 Dec.
Artigo em Japonês | MEDLINE | ID: mdl-15775482
9.
Eur Radiol ; 10(4): 691-3, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10795556

RESUMO

A 72-year-old man presented with a mediastinal mass on chest radiograph. Computed tomography and MR imaging showed that the mass consisted of both fatty and small nodular soft tissue components, highly suggestive of an extramedullary hematopoiesis or a myelolipoma. A CT-guided needle biopsy was next performed and confirmed the diagnosis. We discuss the CT and MR imaging appearances es of this tumor and usefulness of a CT-guided needle biopsy to avoid surgery in asymptomatic patients.


Assuntos
Imageamento por Ressonância Magnética , Neoplasias do Mediastino/diagnóstico , Mielolipoma/diagnóstico , Tomografia Computadorizada por Raios X , Idoso , Humanos , Masculino
10.
J Biol Chem ; 275(28): 21272-7, 2000 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-10801783

RESUMO

Two classes of transcription factors, ETS and bZIP, stand out as key mediators of monocyte commitment and differentiation. The ETS domain factor Spi-1 (also called PU.1) and the bZIP factor NF-IL6 (also called C/EBPbeta) have been shown to be involved in the transcriptional regulation of interleukin-1beta gene (il1b) and other monocyte-specific genes. We now show that these two factors strongly cooperate on the il1b core promoter (-59/+12) in the absence of direct NF-IL6 binding to DNA. Transient transfection assays, using mutated il1b core promoters, showed that the Spi-1, but not the NF-IL6, binding site is absolutely required for functional cooperativity. Furthermore, the NF-IL6 transactivation domain (TAD) is functionally indispensable and more critical than that of Spi-1. Additionally, TAD-deficient NF-IL6 functions as a dominant negative for Spi-1-mediated activation, suggesting the involvement of the bZIP DNA binding domain. This is supported by the demonstration of in vitro interaction between the NF-IL6 bZIP and Spi-1 winged helix-turn-helix (wHTH) DNA binding domains, arguing that NF-IL6 vigorously activates the il1b core promoter via protein-tethered transactivation mediated by Spi-1.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica/imunologia , Interleucina-1/genética , Proteínas Nucleares/metabolismo , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas/metabolismo , Transativadores/metabolismo , Sequência de Bases , Sítios de Ligação , Proteínas Estimuladoras de Ligação a CCAAT , Regulação da Expressão Gênica/efeitos dos fármacos , Células HeLa , Humanos , Lipopolissacarídeos/farmacologia , Ligação Proteica , Proteínas Recombinantes/metabolismo , Acetato de Tetradecanoilforbol/farmacologia , Fatores de Transcrição/metabolismo , Transfecção
11.
Biochem Biophys Res Commun ; 269(1): 219-25, 2000 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-10694503

RESUMO

The effects of the N-linked oligosaccharide inhibitors swainsonine and N-butyldeoxynojirimycin (NB-DNJ) on granulopoiesis was investigated using human bone marrow cells in in vitro liquid and agar cultures. The addition of the inhibitors into cultures containing granulocyte colony-stimulating factor (G-CSF) suppressed maturation from myelocytes into mature neutrophils. Swainsonine did not induce apoptosis, but NB-DNJ induced considerable apoptosis, especially in the presence of G-CSF. This result indicated that the decrease of mature neutrophils by swainsonine was not because of cell degeneration. In the case of NB-DNJ, it was thought to be because of both maturation suppression and apoptosis. In a colony-forming unit-granuloid (CFU-G) colony assay, the number of colonies was increased in the presence of the inhibitors, but the morphology of colonies was predominantly compact, or immature. The inhibitors also suppressed the expressions of mRNAs of CCAAT/enhancer binding protein epsilon (C/EBPepsilon) and G-CSF receptor as markers of terminal neutrophil maturation. These findings suggested that the incompleteness of N-linked oligosaccharide leads to the suppression of terminal neutrophil maturation.


Assuntos
1-Desoxinojirimicina/análogos & derivados , Células da Medula Óssea/citologia , Células da Medula Óssea/efeitos dos fármacos , Neutrófilos/citologia , Neutrófilos/efeitos dos fármacos , Swainsonina/farmacologia , 1-Desoxinojirimicina/farmacologia , Apoptose/efeitos dos fármacos , Sequência de Bases , Células da Medula Óssea/metabolismo , Proteínas Estimuladoras de Ligação a CCAAT , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Ensaio de Unidades Formadoras de Colônias , Primers do DNA/genética , Proteínas de Ligação a DNA/genética , Inibidores Enzimáticos/farmacologia , Inibidores de Glicosídeo Hidrolases , Fator Estimulador de Colônias de Granulócitos/farmacologia , Hematopoese/efeitos dos fármacos , Humanos , Manosidases/antagonistas & inibidores , Neutrófilos/metabolismo , Proteínas Nucleares/genética , Oligossacarídeos/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de Fator Estimulador de Colônias de Granulócitos/genética , Tunicamicina/farmacologia , alfa-Manosidase
12.
Br J Pharmacol ; 129(1): 131-9, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10694212

RESUMO

[(3)H]-oxytocin was used to characterize the oxytocin receptor found in human uterine smooth muscle cells (USMC). Specific binding of [(3)H]-oxytocin to USMC plasma membranes was dependent upon time, temperature and membrane protein concentration. Scatchard plot analysis of equilibrium binding data revealed the existence of a single class of high-affinity binding sites with an apparent equilibrium dissociation constant (K(d)) of 0.76 nM and a maximum receptor density (B(max)) of 153 fmol mg(-1) protein. The Hill coefficient (n(H)) did not differ significantly from unity, suggesting binding to homogenous, non-interacting receptor populations. Competitive inhibition of [(3)H]-oxytocin binding showed that oxytocin and vasopressin (AVP) receptor agonists and antagonists displaced [(3)H]-oxytocin in a concentration-dependent manner. The order of potencies for peptide agonists and antagonists was: oxytocin>[Asu(1,6)]-oxytocin>AVP= atosiban>d(CH(2))(5)Tyr(Me)AVP>[Thr(4),Gly(7)]-oxytocin>dDAVP, and for nonpeptide antagonists was: L-371257>YM087>SR 49059>OPC-21268>SR 121463A>OPC-31260. Oxytocin significantly induced concentration-dependent increase in intracellular Ca(2+) concentration ([Ca(2+)](i)) and hyperplasia in USMC. The oxytocin receptor antagonists, atosiban and L-371257, potently and concentration-dependently inhibited oxytocin-induced [Ca(2+)](i) increase and hyperplasia. In contrast, the V(1A) receptor selective antagonist, SR 49059, and the V(2) receptor selective antagonist, SR 121463A, did not potently inhibit oxytocin-induced [Ca(2+)](i) increase and hyperplasia. The potency order of antagonists in inhibiting oxytocin-induced [Ca(2+)](i) increase and hyperplasia was similar to that observed in radioligand binding assays. In conclusion, these data provide evidence that the high-affinity [(3)H]-oxytocin binding site found in human USMC is a functional oxytocin receptor coupled to [Ca(2+)](i) increase and cell growth. Thus human USMC may prove to be a valuable tool in further investigation of the physiologic and pathophysiologic roles of oxytocin in the uterus. British Journal of Pharmacology (2000) 129, 131 - 139


Assuntos
Músculo Liso/efeitos dos fármacos , Receptores de Ocitocina/efeitos dos fármacos , Útero/efeitos dos fármacos , Antagonistas dos Receptores de Hormônios Antidiuréticos , Arginina Vasopressina/farmacologia , Ligação Competitiva/efeitos dos fármacos , Cálcio/metabolismo , Contagem de Células , Divisão Celular/efeitos dos fármacos , Feminino , Humanos , Hiperplasia/induzido quimicamente , Hiperplasia/patologia , Técnicas In Vitro , Cinética , Ligantes , Músculo Liso/citologia , Ocitocina/análogos & derivados , Ocitocina/farmacologia , Receptores de Ocitocina/agonistas , Receptores de Ocitocina/antagonistas & inibidores , Receptores de Vasopressinas/agonistas , Sistemas do Segundo Mensageiro/efeitos dos fármacos , Útero/citologia , Vasoconstritores/farmacologia
14.
Blood ; 95(8): 2715-8, 2000 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-10753855

RESUMO

The activation status of a recently identified STAT (signal transducers and activators of transcription) factor, LIL-Stat (lipopolysaccharide [LPS]/IL-1-inducible Stat) in adult T-cell leukemia (ATL) cells was investigated by electrophoretic mobility shift assays using nuclear extracts of leukemic cells from 7 patients with ATL and a GAS (gamma interferon activation site)-like element termed LILRE (LPS/IL-1-responsive element), which is found in the human prointerleukin 1beta (IL1B) gene. Spontaneous DNA binding of LIL-Stat was observed in all ATL cells examined. However, in normal human peripheral lymphocytes, DNA binding of LIL-Stat was detected only after stimulation with IL-1. These results demonstrated that LIL-Stat is constitutively activated in ATL cells. Furthermore, our transient transfection studies using LILRE chloramphenicol acetyltransferase (CAT) reporters argue that LIL-Stat in ATL cells functions as a transcriptional activator through binding to the LILRE in the IL1B gene. (Blood. 2000;95:2715-2718)


Assuntos
Regulação Neoplásica da Expressão Gênica , Leucemia de Células T/genética , Fatores de Transcrição/genética , Doença Aguda , Adulto , Humanos , Leucemia de Células T/metabolismo , Transdução de Sinais/genética , Fatores de Transcrição/metabolismo
15.
J Biol Chem ; 274(52): 37240-50, 1999 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-10601288

RESUMO

We have investigated the regulatory role of DNA methylation in the expression of the human histo-blood group ABO genes. The ABO gene promoter region contains a CpG island whose methylation status correlates well with gene expression in the cell lines tested. The CpG island was found hypomethylated in some cell lines that expressed ABO genes, whereas the other cell lines that did not express ABO genes were hypermethylated. Whereas constitutive transcriptional activity of the ABO gene promoter was demonstrated in both expressor and nonexpressor cell lines by transient transfection of reporter constructs containing the ABO gene promoter sequence, HhaI methylase-catalyzed in vitro methylation of the promoter region prior to DNA transfection suppressed the promoter activity when introduced into the expressor gastric cancer cell line KATOIII cells. On the other hand, in the nonexpressor gastric cancer cell line MKN28 cells, treatment with DNA methyltransferase inhibitor 5-aza-2'-deoxycytidine resulted in demethylation of the ABO gene promoter and appearance of A-transferase messages, as well as A-antigens synthesized by A-transferase. Taken together, these studies suggest that DNA methylation of the ABO gene promoter may play an important role in the regulation of ABO gene expression.


Assuntos
Sistema ABO de Grupos Sanguíneos/genética , Metilação de DNA , Regulação da Expressão Gênica , Regiões Promotoras Genéticas , Sequência de Bases , Humanos , Dados de Sequência Molecular , Células Tumorais Cultivadas
16.
J Immunol ; 163(11): 6209-16, 1999 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-10570313

RESUMO

The adhesive function of integrins is regulated through cytoplasmic signaling. The present study was performed to investigate the relevance of cytoplasmic signaling and cytoskeletal assembly to integrin-mediated adhesion induced by chemokines. Adhesion of T cells induced by chemokines macrophage inflammatory protein (MIP)-1alpha and MIP-1beta was inhibited by pertussis toxin, wortmannin, and cytochalasin B, suggesting that both G protein-sensitive phosphatidylinositol (PI) 3-kinase activation and cytoskeletal assemblies are involved. The chemokine-induced T cell adhesion could be mimicked by expression of small G proteins, fully activated H-RasV12, or H-RasV12Y40C mutant, which selectively binds to PI 3-kinase, in T cells, inducing activated form of LFA-1alpha and LFA-1-dependent adhesion to ICAM-1. H-Ras expression also induced F-actin polymerization which colocalized with profilin in T cells. Adult T cell leukemia (ATL) cells spontaneously adhered to ICAM-1, which depended on endogenous MIP-1alpha and MIP-1beta through activation of G protein-sensitive PI 3-kinase. H-Ras signal pathway, leading to PI 3-kinase activation, also induced active configuration of LFA-1 and LFA-1-mediated adhesion of ATL cells, whereas expression of a dominant-negative H-Ras mutant failed to do. Profilin-dependent spontaneous polymerization of F-actin in ATL cells was reduced by PI 3-kinase inhibitors. In this paper we propose that H-Ras-mediated activation of PI 3-kinase can be involved in induction of LFA-1-dependent adhesion of T cells, which is relevant to chemokine-mediated signaling, and that profilin may form an important link between chemokine- and/or H-Ras-mediated signals and F-actin polymerization, which results in triggering of LFA-1 on T cells or leukemic T cells.


Assuntos
Adesão Celular/fisiologia , Proteínas Contráteis , Citoesqueleto/fisiologia , Genes ras/fisiologia , Integrinas/metabolismo , Linfócitos T/fisiologia , Actinas/metabolismo , Adulto , Androstadienos/farmacologia , Artrite Reumatoide , Quimiocina CCL3 , Quimiocina CCL4 , Citocalasina B/farmacologia , Endotélio Vascular/citologia , Endotélio Vascular/fisiologia , Proteínas de Ligação ao GTP/metabolismo , Humanos , Molécula 1 de Adesão Intercelular/metabolismo , Leucemia de Células T , Antígeno-1 Associado à Função Linfocitária/metabolismo , Proteínas Inflamatórias de Macrófagos/metabolismo , Proteínas dos Microfilamentos/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Profilinas , Transdução de Sinais , Wortmanina
17.
Regul Pept ; 84(1-3): 13-9, 1999 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-10535403

RESUMO

Radioligand binding studies with [3H]vasopressin (AVP) were used to determine the affinities of AVP receptor agonists and antagonists for mouse liver and kidney plasma membrane preparations. Both membrane preparations exhibited one class of high-affinity binding site. AVP ligand binding inhibition studies confirmed that mouse liver binding sites belong to the V1A subtype while kidney binding sites belong to the V2 receptor subtype. The affinity of each ligand for mouse V1A receptors was very similar to that for rat V1A receptors, showing differences in Ki values of less than 3-fold. In contrast, several peptide (d(CH2)5Tyr(Me)AVP) and nonpeptide (OPC-21268 and SR 49059) ligands had different affinities for mouse and rat kidney V2 receptors, with differences in Ki values ranging from 14- to 17-fold. These results indicate that mouse and rat kidney V2 receptors show significant pharmacologic differences.


Assuntos
Rim/metabolismo , Fígado/metabolismo , Receptores de Vasopressinas/metabolismo , Animais , Antagonistas dos Receptores de Hormônios Antidiuréticos , Arginina Vasopressina/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos ICR , Ligação Proteica , Ensaio Radioligante , Ratos , Especificidade da Espécie
18.
Eur J Pharmacol ; 378(1): 137-42, 1999 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-10478574

RESUMO

Several studies indicate that oxytocin and vasopressin receptors in the human uterus are heterogeneous. We have investigated whether oxytocin and vasopressin bind to separate receptors or one class of receptors in human uterine smooth muscle cells. [3H]d(CH2)5Tyr(Me)AVP, the vasopressin V1A receptor selective radioligand, was used for comparison of vasopressin binding sites in human uterine and vascular smooth muscle cell membranes. Both membrane preparations exhibited one class of high-affinity binding sites with Kd values of 6.44 and 0.47 nM, Bmax values of 166 and 34.8 fmol/mg protein for uterine and vascular smooth muscle cells, respectively. In vascular preparations, the selective vasopressin V1A receptor antagonist, SR 49059 ((2S) 1-[(2R 3S)-(5-chloro-3-(2-chlorophenyl)- -(3.4-dimethoxybenzenesulfonyl)-3-hydroxy-2,3-dihydro-1H-indole-2- carbonyl]-pyrrolidine-2-carboxamide), showed high affinity with Ki value of 0.98 nM, confirming that these receptors belong to the vasopressin V1A receptor subtype. On the contrary, in uterine preparations, binding of [3H]d(CH2)5Tyr(Me)AVP was more effectively displaced by oxytocin and the oxytocin receptor selective antagonist, L-371257, (1-[1-[4-[ N-Acetyl-4-piperidinyl)oxy]2-methoxybenzoyl]piperidin-4-yl]- 4H-3,1-benzoxazin-2(1H)-one), than vasopressin and SR 49059, suggesting that binding may be due to cross-reaction with the oxytocin receptors. These results suggest that human uterine smooth muscle cells express only a high density of oxytocin receptors.


Assuntos
Músculo Liso Vascular/metabolismo , Miométrio/metabolismo , Receptores de Vasopressinas/metabolismo , Vasopressinas/metabolismo , Sítios de Ligação , Feminino , Humanos , Músculo Liso Vascular/citologia , Ensaio Radioligante , Trítio
19.
Eur J Pharmacol ; 376(3): 239-46, 1999 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-10448882

RESUMO

The systemic hemodynamic and renal responses to conivaptan hydrochloride (YM087; 4'-(2-methyl-1,4,5,6-tetrahydroimidazo[4,5-d][1]benzoazepine -6-carbonyl)-2-phenylbenzanilide monohydrochloride), a vasopressin V1A and V2 receptor antagonist, were determined in pentobarbital-anesthetized dogs after 2 to 3 weeks of rapid right ventricular pacing. Congestive heart failure, characterized by decreases in first derivative of left ventricular pressure (left ventricular d P/dt(max)) and cardiac output, and increases in left ventricular end-diastolic pressure and total peripheral vascular resistance, was induced by chronic rapid right ventricular pacing at 260-280 beats/min. Intravenous administration of conivaptan (0.1 mg/kg) significantly increased left ventricular dP/dt(max) and cardiac output and significantly decreased left ventricular end-diastolic pressure and total peripheral vascular resistance. Conivaptan also increased urine flow and reduced urine osmolality by markedly increasing free water clearance. These results indicate that conivaptan produced hemodynamic improvement and marked aquaresis in dogs with congestive heart failure. Therefore, conivaptan may find clinical use in treating patients with congestive heart failure.


Assuntos
Benzazepinas/uso terapêutico , Fármacos Cardiovasculares/uso terapêutico , Diurese/efeitos dos fármacos , Insuficiência Cardíaca/tratamento farmacológico , Hemodinâmica/efeitos dos fármacos , Receptores de Vasopressinas/uso terapêutico , Fármacos Renais/uso terapêutico , Animais , Antagonistas dos Receptores de Hormônios Antidiuréticos , Benzazepinas/urina , Estimulação Cardíaca Artificial , Fármacos Cardiovasculares/urina , Cães , Feminino , Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/fisiopatologia , Masculino , Fármacos Renais/urina
20.
Clin Exp Pharmacol Physiol ; 26(5-6): 399-403, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10386228

RESUMO

1. YM087 is a newly synthesized non-peptide arginine vasopressin (AVP) antagonist that shows high affinity for both V1A and V2 receptors. In the present study, the V1A and V2 receptor antagonist effects of orally administered YM087 were assessed in conscious rats. 2. In conscious rats, orally administered YM087 (0.1, 0.3 and 1.0 mg/kg) did not affect basal blood pressure, but YM087 dose-dependently inhibited 30 mU/kg, i.v., AVP-induced pressor responses. This inhibition lasted for over 8 h following the oral administration of the highest dose of YM087 (1 mg/kg). 3. In rats deprived of water and food for 16-18 h, oral administration of YM087 (0.1, 0.3, 1 and 3 mg/kg) dose-dependently increased urine volume and reduced urine osmolality, with associated increases in urinary sodium and potassium excretion. However, these increases in electrolyte excretion were lower than those seen at comparable diuretic doses of furosemide (3, 10, 30 and 100 mg/kg, p.o.). 4. Oral administration of YM087 (0.3, 1 and 3 mg/kg) produced a dose-dependent increase in urine volume in rats allowed free access to water, with the diuretic effect peaking 2-4 h post-dosing at all dose levels. The diuretic effect of YM087 was sustained 8-10 h after a dose of 3 mg/kg; this is in contrast with the transient diuresis seen after furosemide (100 mg/kg, p.o.) dosing. 5. The present results demonstrate that YM087 is an orally active AVP antagonist with potent and long-lasting effects. YM087 suppressed V1A receptor-mediated pressor responses to AVP with minimal effects on basal haemodynamics and exerted a diuretic effect without increased electrolyte excretion by inhibiting V2 receptor-mediated water reabsorption.


Assuntos
Benzazepinas/farmacologia , Sistema Cardiovascular/efeitos dos fármacos , Sistema Urinário/efeitos dos fármacos , Vasopressinas/antagonistas & inibidores , Administração Oral , Animais , Arginina Vasopressina/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Masculino , Ratos , Ratos Wistar , Fatores de Tempo , Micção/efeitos dos fármacos
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