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2.
Clin Anat ; 31(5): 734-741, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28960445

RESUMO

Cutaneous nerves have branches called vascular branches (VBs) that reach arteries. VBs are thought to be involved in arterial constriction, and this is the rationale for periarterial sympathectomy as a treatment option for Raynaud's disease. However, the branching patterns and distribution areas of the VBs remain largely unclear. The aim of the present study was to investigate the anatomical structures of the VBs of the cutaneous nerves. Forty hands and forearms were examined to assess the branching patterns and distribution areas of the VBs of the superficial branch of the radial nerve (SBRN), the lateral antebrachial cutaneous nerve (LACN), the medial antebrachial cutaneous nerve (MACN), and the palmar cutaneous branch of the ulnar nerve (PCUN). VBs reaching the radial and ulnar arteries were observed in all specimens. The branching patterns were classified into six types. The mean distance between the radial styloid process and the point where the VBs reached the radial artery was 34.3 ± 4.8 mm in the SBRN and 38.5 ± 15.8 mm in the LACN. The mean distance between the ulnar styloid process and the point where the VBs reached the ulnar artery was 60.3 ± 25.9 mm in the MACN and 43.8 ± 26.0 mm in the PCUN. This study showed that the VBs of the cutaneous nerves have diverse branching patterns. The VBs of the SBRN had a more limited distribution areas than those of the other nerves. Clin. Anat. 31:734-741, 2018. © 2017 Wiley Periodicals, Inc.


Assuntos
Antebraço/irrigação sanguínea , Mãos/irrigação sanguínea , Artéria Radial/inervação , Artéria Ulnar/inervação , Idoso , Idoso de 80 Anos ou mais , Feminino , Antebraço/inervação , Mãos/inervação , Humanos , Masculino , Doença de Raynaud/cirurgia
3.
Climacteric ; 14(1): 31-40, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21067421

RESUMO

OBJECTIVES: Although patients with gynecological malignancies now survive longer due to advances in early diagnosis and therapy, major issues still remain regarding the quality of life for the survivors. Surgical menopause increases the risk of atherosclerosis; however, few studies have investigated the influence of platinum-based adjuvant chemotherapy. This study was conducted to evaluate the effects of platinum-based chemotherapy on atherosclerosis. METHODS: This study enrolled 47 women (26 with ovarian cancers and 21 with endometrial cancers) who underwent surgical treatment, with or without platinum-based adjuvant chemotherapy, according to established protocols between 2007 and 2009. Arterial stiffness was measured by brachial-ankle pulse wave velocity (baPWV) performed before surgery, and subsequently at 12 months after treatment. The flow-mediated dilatation of the brachial artery was measured before and immediately following chemotherapy to evaluate the vascular endothelial damage. Human umbilical vein endothelial cells (HUVECs) were used to evaluate cisplatin-induced vascular endothelial dysfunction in vitro. RESULTS: Although there were no significant differences in the baPWV associated with surgical treatment, platinum-based chemotherapy was associated with an increased baPWV. Significant decreases of flow-mediated dilatation were observed immediately following chemotherapy. An in vitro examination demonstrated that cisplatin attenuated nitric oxide production via inhibition of Akt-eNOS cascades in HUVECs. CONCLUSIONS: This research suggests that platinum-based chemotherapy directly induces vascular endothelial dysfunction and may be a risk factor for the development of atherosclerosis. Therefore, gynecologic cancer survivors should be educated about these potential risks, and informed regarding lifestyle modifications that may benefit their general health.


Assuntos
Antineoplásicos/uso terapêutico , Aterosclerose/fisiopatologia , Cisplatino/uso terapêutico , Endotélio Vascular/efeitos dos fármacos , Óxido Nítrico Sintase Tipo III/metabolismo , Índice Tornozelo-Braço , Velocidade do Fluxo Sanguíneo , Artéria Braquial/diagnóstico por imagem , Calcimicina/farmacologia , Carboplatina/uso terapêutico , Células Cultivadas , Quimioterapia Adjuvante , Neoplasias do Endométrio/terapia , Células Endoteliais/efeitos dos fármacos , Endotélio Vascular/fisiopatologia , Feminino , Humanos , Ionóforos/farmacologia , Pessoa de Meia-Idade , Proteína Oncogênica v-akt/metabolismo , Neoplasias Ovarianas/terapia , Paclitaxel/uso terapêutico , Fosforilação , Triglicerídeos/sangue , Ultrassonografia , Veias Umbilicais/citologia
4.
Neuron ; 9(4): 769-77, 1992 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1382475

RESUMO

Growth factor receptor tyrosine kinases can form stable associations with intracellular proteins that contain src homology (SH) 2 domains, including the p85 regulatory subunit of phosphatidylinositol (PI)-3 kinase. The activation of this enzyme by growth factors is evaluated in PC12 pheochromocytoma cells and NIH 3T3 fibroblasts expressing the pp140c-trk nerve growth factor (NGF) receptor (3T3-c-trk). NGF causes the rapid stimulation of PI-3 kinase activity detected in anti-phosphotyrosine, but not in anti-trk, immunoprecipitates. This effect coincides with the tyrosine phosphorylation of two proteins, with molecular masses of of 100 kd and 110 kd, that coimmunoprecipitate with p85. Similar phosphorylation patterns are induced when an immobilized fusion protein containing the amino-terminal SH2 domain of p85 is used to precipitate tyrosine-phosphorylated proteins. Thus, although NGF produces the rapid activation of PI-3 kinase through a mechanism that involves tyrosine phosphorylation, there is no evidence for tyrosine phosphorylation of p85, or for its ligand-dependent association with the NGF receptor. Perhaps another phosphoprotein may link the NGF receptor to this enzyme.


Assuntos
Genes src , Fatores de Crescimento Neural/farmacologia , Fosfotransferases/metabolismo , Proteínas Tirosina Quinases/genética , Proteínas Proto-Oncogênicas/genética , Proto-Oncogenes , Células 3T3 , Animais , Ativação Enzimática , Fator de Crescimento Epidérmico/farmacologia , Immunoblotting , Insulina/farmacologia , Cinética , Substâncias Macromoleculares , Camundongos , Células PC12 , Fosfatidilinositol 3-Quinases , Fosfotirosina , Proto-Oncogenes/efeitos dos fármacos , Receptor trkA , Tirosina/análogos & derivados , Tirosina/análise
5.
Curr Opin Neurobiol ; 3(3): 352-9, 1993 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8369628

RESUMO

The molecular cloning of genes encoding new neuroactive growth factors and their receptors has greatly enhanced our understanding of important interactions between receptors and signaling molecules. These studies have begun to illuminate some of the mechanisms that allow for specificity in neuronal signaling.


Assuntos
Proteínas Tirosina Quinases/fisiologia , Receptores de Fator de Crescimento Neural/fisiologia , Transdução de Sinais/fisiologia , Animais , Humanos
6.
Cancer Res ; 60(21): 5988-94, 2000 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-11085518

RESUMO

We studied the roles of the phosphatidylinositol 3-kinase (PI-3K)-protein kinase B/Akt-BAD cascade in both cisplatin-resistant Caov-3 and -sensitive A2780 human ovarian cancer cell lines. Treatment of both Caov-3 and A2780 cells with cisplatin but not with the trans-diaminodichloroplatinum (transplatin) isomer stimulated the activation of Akt, and the PI-3K inhibitor wortmannin blocked the cisplatin-induced activation of Akt. Treatment of both Caov-3 and A2780 cells with cisplatin but not with the trans-diaminodichloroplatinum isomer also stimulated the phosphorylation of BAD at both the Ser-112 and Ser-136 sites. Whereas the phosphorylation of BAD at Ser-136 was blocked by treatment with wortmannin, its phosphorylation at Ser-112 was blocked by a MAP/ERK kinase inhibitor, PD98059. Exogenous expression of a dominant-negative Akt in both Caov-3 and A2780 cells decreased the cell viability after treatment with cisplatin. In contrast, no sensitization to cisplatin was observed in cells expressing wild-type Akt. We further examined the role of BAD in the viability after cisplatin treatment using BAD mutants. Exogenous expression of each of the singly substituted BADS112A or BADS136A in both Caov-3 and A2780 cells decreased the viability after treatment with cisplatin to a degree intermediate between that caused by exogenous expression of wild-type BAD and doubly substituted BAD2SA. Cisplatin did not stimulate the phosphorylation of BAD Ser-136, but did stimulate the phosphorylation of BAD Ser-112 in cells expressing a dominant-negative Akt, suggesting that BAD Ser-136 but not Ser-112 was phosphorylated by Akt. Our findings suggest that cisplatin-induced DNA damage causes the phosphorylation of both BAD Ser-112 via an extracellular signal-regulated protein kinase (ERK) cascade and BAD Ser-136 via a PI-3K-protein kinase B/Akt cascade and that inhibition of either of these cascades sensitizes ovarian cancer cells to cisplatin.


Assuntos
Antineoplásicos/farmacologia , Proteínas de Transporte/metabolismo , Cisplatino/farmacologia , Sistema de Sinalização das MAP Quinases/fisiologia , Neoplasias Ovarianas/metabolismo , Proteínas Proto-Oncogênicas/fisiologia , Adenocarcinoma Papilar/tratamento farmacológico , Adenocarcinoma Papilar/metabolismo , Androstadienos/farmacologia , Proteínas de Transporte/antagonistas & inibidores , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Feminino , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/enzimologia , Fosfatidilinositol 3-Quinases/metabolismo , Fosfatidilinositol 3-Quinases/fisiologia , Fosforilação/efeitos dos fármacos , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Serina-Treonina Quinases/fisiologia , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-akt , Serina/metabolismo , Células Tumorais Cultivadas , Wortmanina , Proteína de Morte Celular Associada a bcl
7.
Cancer Res ; 60(19): 5376-81, 2000 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-11034074

RESUMO

Emerging evidence indicates that sex steroid hormones regulate telomerase in target tissues. We have reported that estrogen activates telomerase through transactivation of the telomerase catalytic subunit, human telomerase reverse transcriptase (hTERT). Progesterone usually antagonizes estrogen action in reproductive organs, but the effect on telomerase remains unclear. In this study, we examine the effects of progesterone on the gene expression of hTERT in breast and endometrial cancer cell lines expressing progesterone receptor. Progesterone significantly induced hTERT mRNA expression within 3 h after exposure. This transient effect peaked at 12 h and then decreased. In contrast, exposure to progesterone for > 48 h antagonized estrogen effects and inhibited the estrogen-induced activation of hTERT expression; the cyclin-dependent kinase inhibitor p21/Waf1/Cip1 plays an integral role in this inhibition. Thus, progesterone exerts diverse effects on hTERT mRNA expression in a time-dependent manner. We also found that the mitogen-activated protein kinase signaling pathway mediates both the short-term and long-term effects of progesterone on hTERT gene expression. These findings support the notion that hTERT gene is a target of both estrogen and progesterone.


Assuntos
Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Medroxiprogesterona/farmacologia , Congêneres da Progesterona/farmacologia , RNA , Telomerase/genética , Neoplasias da Mama/enzimologia , Neoplasias da Mama/genética , Proteínas de Ligação a DNA , Interações Medicamentosas , Neoplasias do Endométrio/enzimologia , Neoplasias do Endométrio/genética , Estradiol/farmacologia , Antagonistas de Estrogênios/farmacologia , Feminino , Regulação Enzimológica da Expressão Gênica/fisiologia , Regulação Neoplásica da Expressão Gênica/fisiologia , Humanos , Sistema de Sinalização das MAP Quinases/fisiologia , Progesterona/fisiologia , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Receptores de Progesterona/biossíntese , Receptores de Progesterona/fisiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Telomerase/biossíntese , Transcrição Gênica/efeitos dos fármacos , Células Tumorais Cultivadas
8.
Cancer Res ; 59(20): 5133-42, 1999 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-10537288

RESUMO

Although gonadotropin-releasing hormone agonists (GnRHa) have been used in the therapy of the endocrine-dependent cancers, their biological mechanism remained obscure. We have studied the roles of mitogen-activated protein kinase family in the antiproliferative effect of GnRHa on the Caov-3 human ovarian cancer cell line. Reverse transcription-PCR assays confirmed mRNA for GnRH receptor in Caov-3 cells. In the presence of 1 microM GnRHa, the proliferation of cells was significantly reduced to 76% of controls after 24 h, and the effect was sustained up to 4 days. Although GnRHa had no effect on the activation of the Jun N-terminal kinase (JNK), treatment of Caov-3 cells with GnRHa activated extracellular signal-regulated protein kinase (ERK), and its effect was more than that induced by GnRH. Activation of ERK by GnRHa occurred within 5 min, with the maximum occurring at 3 h and sustained until 24 h. GnRHa also activated ERK kinase (mitogen-activated protein/ERK kinase) and resulted in an increase in phosphorylation of son of sevenless (Sos), and Shc. Furthermore, we examined the mechanism by which GnRHa induced ERK activation. Both pertussis toxin (10 ng/ml), which inactivates Gi/Go proteins, and expression of a peptide derived from the carboxyl terminus of the beta-adrenergic receptor kinase I, which specifically blocks signaling mediated by the betagamma subunits of G proteins, blocked the GnRHa-induced ERK activation. Phorbol 12-myristate 13-acetate (PMA) also induced the ERK activity, but pretreatment of the cultured cells with PMA to down-regulate protein kinase C did not abolish the activation of ERK by GnRHa. Elimination of extracellular Ca2+ by EGTA also did not abolish the activation of ERK by GnRHa. To examine the role of ERK cascade in the antiproliferative effect of GnRHa, PD98059, an inhibitor of mitogen-activated protein/ERK kinase, was used. This inhibitor canceled the antiproliferative effect of GnRHa and apparently reversed the GnRH-induced dephosphorylation of the retinoblastoma protein, the hyperphosphorylation of which is a hallmark of G1-S transition in the cell cycle. These results provide evidence that GnRHa stimulation of ERK activity may be mediated by Gbetagamma protein, not by PMA-sensitive protein kinase C nor extracellular Ca2+ in the Caov-3 human ovarian cancer cell line, suggesting that this cascade may play an important role in the antiproliferative effect of GnRHa.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Proteínas Adaptadoras de Transporte Vesicular , Antineoplásicos Hormonais/farmacologia , Proteínas Quinases JNK Ativadas por Mitógeno , Leuprolida/farmacologia , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Neoplasias Ovarianas/tratamento farmacológico , Cálcio/metabolismo , Divisão Celular/efeitos dos fármacos , Ativação Enzimática , Feminino , Proteínas de Ligação ao GTP/fisiologia , Humanos , MAP Quinase Quinase 4 , Proteína Quinase 3 Ativada por Mitógeno , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Neoplasias Ovarianas/enzimologia , Neoplasias Ovarianas/patologia , Fosforilação , Proteína Quinase C/fisiologia , Proteínas/metabolismo , Receptores LHRH/análise , Proteína do Retinoblastoma/metabolismo , Proteínas Adaptadoras da Sinalização Shc , Proteína Son Of Sevenless de Drosófila/metabolismo , Proteína 1 de Transformação que Contém Domínio 2 de Homologia de Src , Células Tumorais Cultivadas
9.
Endocrinology ; 133(1): 46-56, 1993 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7686484

RESUMO

A PC-12 pheochromocytoma cell line is described with roughly equivalent levels of functional receptors for nerve growth factor (NGF), epidermal growth factor (EGF), and insulin. Each of these receptors undergoes autophosphorylation upon binding of their respective ligands, and causes the activation of phosphatidylinositol-3 kinase via a mechanism involving tyrosine phosphorylation. In the case of insulin, this activation is due to the tyrosine phosphorylation of its major cellular substrate, IRS-1. Despite the presence of functional receptors in these cells, insulin does not stimulate the activity of the mitogen-activated protein (MAP) kinase, despite a 5- to 8-fold activation observed with both NGF and EGF under the same conditions. This failure to activate MAP kinase was not due to the insulin-dependent dephosphorylation of the enzyme, but correlated with the lack of activation of the MAP kinase kinase, although this enzyme was also activated by NGF and EGF. Similarly, the activation of the raf and ras protooncogenes in these cells was not observed with insulin, whereas NGF and EGF produced marked activation. In addition, insulin-dependent induction of the c-fos protein was impaired, in comparison to NGF. In contrast to a lack of effect on the MAP kinase pathway, these PC-12 cells were metabolically responsive to insulin, exhibiting increases in glucose, lipid, and protein synthesis in response to the hormone. The differential responses of phosphorylation events to insulin, NGF, and EGF in these cells indicates that divergence of signaling pathways may occur at or near the insulin receptor.


Assuntos
Insulina/farmacologia , Células PC12/metabolismo , Transdução de Sinais/fisiologia , Animais , Proteínas Quinases Dependentes de Cálcio-Calmodulina , Ativação Enzimática/efeitos dos fármacos , Fator de Crescimento Epidérmico/farmacologia , Éteres Cíclicos/farmacologia , Expressão Gênica , Genes fos/genética , Glicosilação , Guanosina Trifosfato/metabolismo , Fatores de Crescimento Neural/farmacologia , Ácido Okadáico , Fosfatidilinositol 3-Quinases , Fosfatidilinositóis/metabolismo , Fosforilação , Fosfotransferases/metabolismo , Fosfotirosina , Proteínas Quinases/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Ratos , Receptor de Insulina/metabolismo , Tirosina/análogos & derivados , Tirosina/metabolismo
10.
Endocrinology ; 128(6): 2791-8, 1991 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1903696

RESUMO

We investigated the effect of tumor necrosis factor-alpha (TNF alpha), a product of activated macrophages, on the release of arachidonate from dispersed anterior pituitary cells. Primary cultures of anterior pituitary cells from rats were preincubated with [3H]arachidonate to label their phospholipid-containing components. The cells were then washed and incubated with vehicle or test agents, and PRL release into the medium and [3H]arachidonate cleaved from phospholipid were measured. TNF alpha significantly increased the release of both PRL and [3H] arachidonate release in a time- and dose-dependent manner. Other cytokines, such as interleukin-1 alpha, interleukin-1 beta, and gamma-interferon, had no effect on [3H]arachidonate release. To define the role of calcium in TNF alpha-induced arachidonate release, dispersed pituitary cells were incubated with low calcium medium, which decreased arachidonate release in response to TNF alpha. TNF alpha potentiated the release of [3H]arachidonate and PRL promoted by phospholipase-A2 and melittin, and markedly shifted the dose-response curve to the left. Inhibitors of phospholipase-A2, such as p-bromophenacyl bromide and quinacrine, had no effect on TNF alpha-induced [3H]arachidonate and PRL release. BW755C, an inhibitor of the conversion of arachidonate to its metabolites, decreased TNF alpha-induced PRL release, while indomethacin, a prostaglandin synthesis inhibitor, had no effect on TNF alpha-induced PRL release. These data indicate that arachidonate metabolites may be involved in the process of TNF alpha-induced PRL release.


Assuntos
Ácidos Araquidônicos/metabolismo , Adeno-Hipófise/metabolismo , Prolactina/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , 4,5-Di-Hidro-1-(3-(Trifluormetil)Fenil)-1H-Pirazol-3-Amina/farmacologia , Animais , Ácido Araquidônico , Cálcio/metabolismo , Meios de Cultura , Feminino , Indometacina/farmacologia , Meliteno/farmacologia , Fosfolipases A/farmacologia , Fosfolipases A2 , Adeno-Hipófise/citologia , Ratos , Ratos Endogâmicos
11.
Endocrinology ; 138(12): 5275-81, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9389511

RESUMO

The GT1-1 GnRH neuronal cell lines exhibit highly differentiated properties of GnRH neurons. We have used GT1-1 cells to study the roles of norepinephrine (NE), membrane depolarization, calcium influx, and phorbol esters in the regulation of mitogen-activated protein (MAP) kinase. NE, which is known to stimulate the release of GnRH, induced MAP kinase activity, the tyrosine phosphorylation of MAP kinase, and MAP kinase kinase activity. Forskolin led to activation of MAP kinase comparable with that induced by NE, and a selective inhibitor of cAMP-dependent protein kinase, H8, attenuated the NE-induced activation of MAP kinase. On the other hand, elimination of extracellular calcium by EGTA completely blocked NE-induced tyrosine phosphorylation of MAP kinase, and a selective inhibitor of calcium/calmodulin-dependent protein kinase, KN-62, attenuated the NE-induced activation of MAP kinase. Furthermore, depolarization of GT1-1 cells with 75 mM KCl, 10 microM BayK 8644, or 1 microM calcium ionophore (A23187) induced rapid tyrosine phosphorylation of MAP kinase. The omission of calcium from the extracellular medium completely abolished these effects of tyrosine phosphorylation of MAP kinase. Phorbol 12-myristate 13-acetate (PMA) also induced MAP kinase activity, but pretreatment of the cultured cells with PMA to down-regulate protein kinase C did not abolish the activation of MAP kinase by NE. In addition, although phosphorylation of Raf-1 kinase was stimulated by PMA, this phosphorylation was not induced by either NE or A23187. These results demonstrate that NE activates MAP kinase directly in GT1-1 cells, and that the effect of NE is mediated by increase in the cAMP level and by calcium influx, but not by PMA-sensitive protein kinase C or Raf-1 kinase.


Assuntos
Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Hormônio Liberador de Gonadotropina/metabolismo , Quinases de Proteína Quinase Ativadas por Mitógeno , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Norepinefrina/farmacologia , Animais , Cálcio/metabolismo , Linhagem Celular , Eletrofisiologia , Inibidores Enzimáticos/farmacologia , MAP Quinase Quinase 1 , MAP Quinase Quinase 2 , Camundongos , Neurônios/fisiologia , Fosforilação , Proteína Quinase C/metabolismo , Inibidores de Proteínas Quinases , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Tirosina Quinases/metabolismo , Proteínas Proto-Oncogênicas c-raf/metabolismo , Células Tumorais Cultivadas , Tirosina/metabolismo
12.
Endocrinology ; 136(5): 2082-7, 1995 May.
Artigo em Inglês | MEDLINE | ID: mdl-7536662

RESUMO

The regulation of mitogen-activated protein (MAP) kinase by oxytocin in cultured human uterine myometrial cells was investigated. Oxytocin caused the rapid stimulation of MAP kinase activity detected in 32P incorporation of MAP-2. Oxytocin also stimulated the phosphorylation of MAP kinase detected in incorporation of [32P]orthophosphate into MAP kinase. Furthermore, oxytocin induced the tyrosine phosphorylation of MAP kinase. The oxytocin-dependent increase in the tyrosine phosphorylation of MAP kinase displayed a transient time course and was dependent on the concentration of oxytocin applied to the cells. Furthermore, we examined the mechanism by which oxytocin induced MAP kinase phosphorylation. Islet-activating protein (100 ng/ml), which inactivates Gi/Go proteins, blocked the oxytocin-induced phosphorylation of MAP kinase. Moreover, 1 microM ritodrine, which is known to relax uterine muscle contraction, attenuated oxytocin-induced MAP kinase activity and phosphorylation. These results provide evidence that oxytocin acutely activates MAP kinase through an islet-activating protein-sensitive G-protein in human uterine myometrial cells, suggesting that this new pathway may play an important role in the biological action of oxytocin on these cells.


Assuntos
Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Miométrio/enzimologia , Ocitocina/farmacologia , Período Pós-Parto/metabolismo , Proteínas Quinases Dependentes de Cálcio-Calmodulina/isolamento & purificação , Células Cultivadas , Cesárea , Ativação Enzimática , Fator de Crescimento Epidérmico/farmacologia , Feminino , Humanos , Cinética , Miométrio/efeitos dos fármacos , Fosforilação , Fosfotirosina , Gravidez , Ritodrina/farmacologia , Tirosina/análogos & derivados , Tirosina/análise , Tirosina/metabolismo
13.
Endocrinology ; 138(8): 3103-11, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9231756

RESUMO

In this study, prostaglandin (PG) F2alpha was found to activate mitogen-activated protein (MAP) kinase and MAP kinase kinase (MEK) in cultured rat puerperal uterine myometrial cells. PGF2alpha stimulation also led to an increase in phosphorylation of raf-1, son of sevenless (SOS), and Shc. Furthermore, we examined the mechanism by which PGF2alpha induced MAP kinase phosphorylation. Both pertussis toxin (10 ng/ml), which inactivates Gi/Go proteins, and expression of a peptide derived from the carboxyl terminus of the beta-adrenergic receptor kinase 1 (betaARK1), which specifically blocks signaling mediated by the betagamma subunits of G proteins, blocked the PGF2alpha-induced activation of MAP kinase. Ritodrine (1 microM), which is known to relax uterine muscle contraction, attenuated PGF2alpha-induced tyrosine phosphorylation of MAP kinase. Moreover, to examine the role of MAP kinase pathway in uterine contraction, an inhibitor of MEK activity, PD098059, was used. Although MEK inhibitor had no effect on PGF2alpha-induced calcium mobilization, this inhibitor partially inhibited PGF2alpha-induced uterine contraction. These results provide evidence that PGF2alpha stimulates the MAP kinase signaling pathway in cultured rat puerperal uterine myometrial cells through Gbetagamma protein, suggesting that this new pathway may play an important role in the biological action of PGF2alpha on these cells.


Assuntos
Proteínas Quinases Dependentes de Cálcio-Calmodulina/fisiologia , Dinoprosta/farmacologia , Período Pós-Parto/fisiologia , Contração Uterina/fisiologia , Animais , Proteínas Quinases Dependentes de Cálcio-Calmodulina/análise , Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Células Cultivadas , Ativação Enzimática , Feminino , Flavonoides/farmacologia , Quinases de Proteína Quinase Ativadas por Mitógeno , Miométrio/citologia , Miométrio/enzimologia , Toxina Pertussis , Fosforilação , Plasmídeos , Gravidez , Inibidores de Proteínas Quinases , Proteínas Quinases/análise , Proteínas Quinases/fisiologia , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-raf , Ratos , Ratos Wistar , Ritodrina/farmacologia , Tocolíticos/farmacologia , Tirosina/metabolismo , Fatores de Virulência de Bordetella/farmacologia
14.
Endocrinology ; 140(2): 722-31, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9927299

RESUMO

The regulation of mitogen-activated protein (MAP) kinase by endothelin-1 (ET-1) in cultured rat puerperal uterine myometrial cells was investigated. ET-1 caused the rapid stimulation of MAP kinase activity. ET-1-induced MAP kinase activation is neither extracellular Ca2+- nor intracellular Ca2+-dependent. ET-1 stimulation also led to an increase in phosphorylation of son-of-sevenless (SOS), and transfection of dominant negative SOS attenuated the ET-1-induced MAP kinase activity. Phorbol-12-myristate 13-acetate (PMA) also induced the MAP kinase activity, but pretreatment of the cultured cells with PMA, to down-regulate protein kinase C (PKC), did not abolish the activation of MAP kinase by ET-1. In addition, down-regulation of PKC had no effect on ET-1-induced SOS phosphorylation. Pertussis toxin, which inactivates Gi/Go proteins, blocked the ET-1-induced MAP kinase activation but not the PMA-induced MAP kinase activation. The results suggested that MAP kinase is acutely activated by ET-1 through a pertussis toxin-sensitive G protein and SOS, not through the PMA-sensitive PKC. In addition, although reverse-transcriptase PCR assays detected messenger RNA for both ET- 1 receptor subtypes in cultured rat puerperal uterine myometrial cells, ET-1-induced MAP kinase activity and uterine contraction were blocked by treatment with BQ485, an antagonist selective for an ET type A receptor (but not by BQ788, an ET type B receptor antagonist). Ritodrine, which is known to relax uterine muscle contraction, attenuated ET-1-induced MAP kinase activity. We further examined the role of MAP kinase pathway in uterine contraction using an inhibitor of MEK activity, PD098059. This inhibitor completely inhibited the ET-1-induced MAP kinase activation and partially, but significantly, inhibited the ET-1-induced uterine contraction. These results indicate that ET-1-induced MAP kinase signaling cascade may play an important role in the ET-1-induced uterine contraction.


Assuntos
Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Endotelina-1/farmacologia , Período Pós-Parto/fisiologia , Contração Uterina/fisiologia , Útero/efeitos dos fármacos , Animais , Azepinas/farmacologia , Cálcio/farmacologia , Antagonistas dos Receptores de Endotelina , Ativação Enzimática/efeitos dos fármacos , Ativação Enzimática/fisiologia , Feminino , Proteínas de Ligação ao GTP/fisiologia , Proteínas de Membrana/metabolismo , Quinases de Proteína Quinase Ativadas por Mitógeno , Oligopeptídeos/farmacologia , Toxina Pertussis , Fosforilação/efeitos dos fármacos , Gravidez , Proteína Quinase C/metabolismo , Inibidores de Proteínas Quinases , Ratos , Receptor de Endotelina A , Ritodrina/farmacologia , Proteínas Son Of Sevenless , Útero/fisiologia , Fatores de Virulência de Bordetella/farmacologia
15.
J Endocrinol ; 157(2): 267-74, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9659290

RESUMO

Gonadotrophin-releasing hormone (GnRH) induces the release of gonadotrophins via an increase in cytosolic Ca2+ concentration ([Ca2+]). Rab3B, a member of the small GTP-binding protein Rab family, is known to be involved in Ca(2+)-regulated exocytosis in pituitary cells. However, it is not known whether Rab3B functions in the physiological process regulated by GnRH in gonadotrophs. In this study using antisense oligonucleotide against Rab3B (AS-Rab3B) we determined that Rab3B is involved in GnRH-induced gonadotrophin release. Rab3B immunopositive cells were reduced in 24% of pituitary cells by AS-Rab3B. This treatment did not affect the population of gonadotrophs or the intracellular contents of gonadotrophins. However, AS-Rab3B significantly inhibited the total amount of basal and GnRH-induced gonadotrophin released from pituitary cells. These results show that Rab3B is involved in basal and GnRH-induced gonadotrophins release but not the storage of gonadotrophins. Next, the changes in [Ca2+] and exocytosis in gonadotrophs treated with AS-Rab3B were compared among Rab3B-positive and -negative cells. The change in [Ca2+] was not different in the two groups, but exocytosis was significantly inhibited in Rab3B-negative cells. These results suggest that Rab3B is essential for GnRH-regulated exocytosis downstream of cytosolic Ca2+ in gonadotrophs.


Assuntos
Proteínas de Ligação ao GTP/fisiologia , Hormônio Liberador de Gonadotropina/farmacologia , Gonadotropinas Hipofisárias/metabolismo , Oligonucleotídeos Antissenso/farmacologia , Adeno-Hipófise/metabolismo , Animais , Cálcio/metabolismo , Células Cultivadas , Exocitose/efeitos dos fármacos , Feminino , Hormônio Foliculoestimulante/metabolismo , Immunoblotting , Hormônio Luteinizante/metabolismo , Microscopia de Fluorescência , Adeno-Hipófise/efeitos dos fármacos , Ratos , Ratos Wistar , Proteínas rab3 de Ligação ao GTP
16.
J Endocrinol ; 178(3): 417-26, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12967334

RESUMO

Proliferation of vascular smooth muscle cells (VSMC) plays a major role as an initiating event of atherosclerosis. Although estrogen directly inhibits the proliferation of VSMC, the mechanism has not been firmly established. In addition, the effect of raloxifene on VSMC remains unknown. 17Beta-estradiol (E(2)) and raloxifene significantly inhibited the growth of VSMC under growth-stimulated conditions. Since mitogen-activated protein (MAP) kinases have been implicated in VSMC proliferation, the role of MAP kinases in both the E(2)- and raloxifene-induced growth inhibition of VSMC was studied. Both E(2) and raloxifene caused rapid, transient phosphorylation and activation of p38 that was not affected by actinomycin D and was blocked by ICI 182,780. In contrast with p38 phosphorylation, extracellular signal-regulated protein kinase (ERK) phosphorylation was significantly inhibited and c-Jun N-terminal kinase (JNK) phosphorylation was not changed by E(2). Because VSMC expressed both estrogen receptor (ER) alpha and ERbeta, it is not known which of them mediates the E(2)-induced phosphorylation of p38. Although E(2) did not affect the p38 phosphorylation in A10 smooth muscle cells, which express ERbeta but not ERalpha, transfection of ERalpha expression vector into A10 cells rendered them susceptible to induction of p38 phosphorylation by E(2). We then examined whether E(2) and raloxifene induce apoptosis through a p38 cascade. Both E(2) and raloxifene induced apoptosis under growth-stimulated conditions. The p38 inhibitor SB 203580 completely blocked the E(2)-induced apoptosis. Our findings suggest that both E(2)- and raloxifene-induced inhibition of VSMC growth is due to induction of apoptosis through a p38 cascade whose activation is mediated by ERalpha via a nongenomic mechanism.


Assuntos
Apoptose , Estradiol/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Músculo Liso Vascular/metabolismo , Cloridrato de Raloxifeno/farmacologia , Animais , Aorta , Western Blotting/métodos , Linhagem Celular , Células Cultivadas , Relação Dose-Resposta a Droga , Ativação Enzimática , Humanos , Marcação In Situ das Extremidades Cortadas , Músculo Liso Vascular/citologia , Músculo Liso Vascular/efeitos dos fármacos , Coelhos , Ratos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteínas Quinases p38 Ativadas por Mitógeno
17.
J Endocrinol ; 178(2): 319-29, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12904179

RESUMO

The proliferation of vascular smooth muscle cells (VSMC) is a crucial pathophysiological process in the development of atherosclerosis. Although estrogen is known to inhibit the proliferation of VSMC, the mechanism responsible for this effect remains to be elucidated. In addition, the effect of raloxifene on VSMC remains unknown. We have shown here that 17beta-estradiol (E(2)) and raloxifene significantly inhibited the platelet-derived growth factor (PDGF)-stimulated proliferation of cultured human VSMC. Flow cytometry demonstrated that PDGF-stimulated S-phase progression of the cell cycle in VSMC was also suppressed by E(2) or raloxifene. We found that PDGF-induced phosphorylation of retinoblastoma protein (pRb), whose hyperphosphorylation is a hallmark of the G1-S transition in the cell cycle, was significantly inhibited by E(2) and raloxifene. These effects were associated with a decrease in cyclin D1 expression, without a change in cyclin-dependent kinase 4 or cyclin-dependent kinase inhibitor, p27(kip1) expression. ICI 182,780 abolished the inhibitory effects of E(2) and raloxifene on PDGF-induced pRb phosphorylation. Next, we examined which estrogen receptor (ER) is necessary for these effects of E(2) and raloxifene. Since VSMC express both ERalpha and ERbeta, A10, a rat aortic smooth muscle cell line that expresses ERbeta but not ERalpha, was used. The dose-dependent stimulation of A10 cell proliferation by PDGF was not inhibited by E(2) or raloxifene in contrast to the results obtained in VSMC. Moreover, E(2) and raloxifene significantly inhibited the PDGF-induced cyclin D1 promoter activity in A10 cells transfected with cDNA for ERalpha but not in the parental cells. These results suggested that E(2) and raloxifene exert an antiproliferative effect in VSMC treated with PDGF, at least in part through inhibition of pRb phosphorylation, and that the inhibitory effects of E(2) and raloxifene may be mainly mediated by ERalpha.


Assuntos
Estradiol/análogos & derivados , Estradiol/farmacologia , Fase G1 , Músculo Liso Vascular/citologia , Cloridrato de Raloxifeno/farmacologia , Moduladores Seletivos de Receptor Estrogênico/farmacologia , Animais , Aorta , Western Blotting/métodos , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Células Cultivadas , Ciclina D1/metabolismo , Depressão Química , Receptor alfa de Estrogênio , Citometria de Fluxo , Fulvestranto , Humanos , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Fosforilação/efeitos dos fármacos , Fator de Crescimento Derivado de Plaquetas/farmacologia , Ratos , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo , Proteína do Retinoblastoma/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transfecção/métodos
18.
Chest ; 94(6): 1127-32, 1988 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3191755

RESUMO

The bronchial venous system closely communicates with the pulmonary circulation. To assess the changes in the bronchial circulation in chronic pulmonary venous hypertension, fiberoptic bronchoscopy and right heart catheterization were performed in 31 patients with mitral stenosis. Nonpulsatile submucosal vessel dilatation, consistently seen in all patients and called the vessel dilatation score, was assessed visually by three independent bronchoscopists. The vessel dilatation score was correlated more closely with pulmonary artery wedge pressure (r = 0.687) (p less than 0.001) than to mean pulmonary artery pressure (r = 0.531) (p less than 0.01) and right atrial pressure (r = 0.178) (NS). The vessel dilatation score decreased after reduction of the left atrial load by surgery. These results suggest that the dilated vessels observed in patients with mitral stenosis are bronchial veins that are engorged secondary to increased blood flow via bronchopulmonary anastomoses.


Assuntos
Brônquios/irrigação sanguínea , Hipertensão Pulmonar/fisiopatologia , Adulto , Idoso , Broncoscopia , Cateterismo Cardíaco , Doença Crônica , Dilatação Patológica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estenose da Valva Mitral/fisiopatologia , Circulação Pulmonar , Pressão Propulsora Pulmonar , Veias
19.
Obstet Gynecol ; 74(3 Pt 2): 469-71, 1989 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-2548137

RESUMO

A case is reported of hydramnios due to excessive fetal urine production associated with congenital mesoblastic nephroma. Rapid growth of a right renal tumor and excessive fetal urine production were detected by measuring the size of the tumor and hourly fetal urine production during the development of hydramnios between 28-34 weeks of gestation. A female infant weighing 2200 g was born at 34 weeks' gestation. She lost 18% of her birth weight in the first 48 hours because of neonatal polyuria. Right nephrectomy and ureterectomy were performed 2 days after birth. After the operation, the neonatal polyuria improved dramatically. The right renal tumor was identified histologically as a mesoblastic nephroma. The importance is stressed of early and correct antenatal diagnosis of a renal tumor and precise estimation of urine production for postnatal management of hemodynamic change in cases of mesoblastic nephroma.


Assuntos
Neoplasias Renais/congênito , Poli-Hidrâmnios/etiologia , Tumor de Wilms/congênito , Adulto , Feminino , Humanos , Recém-Nascido , Gravidez , Urina
20.
Sarcoidosis Vasc Diffuse Lung Dis ; 18(2): 133-7, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11436533

RESUMO

Combination therapy has proved useful in infectious, rheumatologic, and oncologic diseases. The role of combination therapy in sarcoidosis is less defined. A stepwise approach to therapy in sarcoidosis treatment includes multiple agents, such as topical and systemic corticosteroids. The introduction of cytotoxic agents has led to the combination of these drugs with lowered doses of corticosteroids. Recently, the combination of cytotoxic and immune modifiers has been used for some cases of refractory sarcoidosis. The rationale use of combination therapy may enhance efficacy with reduced toxicity.


Assuntos
Corticosteroides/uso terapêutico , Fatores Imunológicos/uso terapêutico , Sarcoidose/tratamento farmacológico , Corticosteroides/administração & dosagem , Terapia Combinada , Humanos , Fatores Imunológicos/administração & dosagem
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