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1.
Adv Exp Med Biol ; 789: 449-454, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23852528

RESUMO

The aim of this study was to develop a NIRS-based neurofeedback system to modulate activity in the prefrontal cortex (PFC). We evaluated the effectiveness of the system in terms of separability of changes in oxy-Hb and its derivative. Training with neurofeedback resulted in higher separability than training without neurofeedback or no training, suggesting that the neurofeedback system could enhance self-control of PFC activity. Interestingly, the dorsolateral PFC exhibited enhanced activity and high separability after neurofeedback training. These observations suggest that the neurofeedback system might be useful for training subjects to regulate emotions by self-control of dorsolateral PFC activity.


Assuntos
Aprendizagem/fisiologia , Neurorretroalimentação/fisiologia , Córtex Pré-Frontal/fisiologia , Humanos , Oxiemoglobinas/metabolismo , Córtex Pré-Frontal/metabolismo , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Adulto Jovem
2.
Neuron ; 13(2): 427-42, 1994 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7520255

RESUMO

Myelin proteolipid protein (PLP), the major myelin protein in the CNS, has been thought to function in myelin assembly. Thus, mutations within the gene coding for PLP (Plp) cause hypomyelination, such as the jimpy phenotype in mice and Pelizaeus-Merzbacher disease in humans. However, these mutants often exhibit premature death of oligodendrocytes, which form CNS myelin. To elucidate the functional roles of Plp gene products in the maturation and/or survival of oligodendrocytes, we produced transgenic mice overexpressing the Plp gene by introducing extra wild-type mouse Plp genes. Surprisingly, transgenic mice bearing 4 more Plp genes exhibited dysmyelination in the CNS, whereas those with 2 more Plp genes showed normal myelination at an early age (3 weeks after birth), but later developed demyelination. Overexpression of the Plp gene resulted in arrested maturation of oligodendrocytes, and the severity of arrest was dependent on the extent of overexpression. Overexpression also led to oligodendrocyte cell death, apparently caused by abnormal swelling of the Golgi apparatus. Thus, tight regulation of Plp gene expression is necessary for normal oligodendrocyte differentiation and survival, and its overexpression can be the cause of both dys- and demyelination.


Assuntos
Doenças Desmielinizantes/genética , Proteínas da Mielina/genética , Fibras Nervosas Mielinizadas/patologia , Neuroglia/patologia , Animais , Sequência de Bases , Encéfalo/fisiopatologia , Clonagem Molecular , Primers do DNA , Doenças Desmielinizantes/patologia , Feminino , Expressão Gênica , Masculino , Camundongos , Camundongos Mutantes , Camundongos Transgênicos , Dados de Sequência Molecular , Proteína Proteolipídica de Mielina , Oligodendroglia/patologia , Linhagem , RNA Mensageiro/genética , Mapeamento por Restrição
3.
Endocrinology ; 135(3): 826-33, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7915230

RESUMO

Pituitary adenylate cyclase-activating polypeptide-38 (PACAP38) is a neuropeptide related to vasoactive intestinal peptide-secretin-glucagon which stimulates adenylate cyclase in cultured rat pituitary cells and stimulates LH and FSH release in vitro and in vivo. Because the cAMP-protein kinase-A pathway regulates the gonadotropin subunit messenger RNAs (mRNAs) and modulates GnRH-stimulated gonadotropin secretion in vitro, we examined the effects of PACAP38 on gonadotropin secretion and subunit mRNA levels. Anterior pituitary cells were prepared from 7-week-old male rats castrated at 5 weeks of age. In monolayer cultures stimulated with GnRH, 0.1-10 nM PACAP38 decreased (P < 0.05) the EC50 for GnRH dose-dependently without affecting the maximum LH secretory response. Cells were next stimulated with 1-min pulses of 2.5 nM GnRH every hour for 9 h in the absence or presence of 10 nM PACAP38, which was perifused continuously. The amplitude of GnRH-induced LH, FSH, and alpha-subunit secretory episodes from PACAP38-treated cells rose (P < 0.01) gradually to 233 +/- 54%, 197 +/- 44%, and 378 +/- 104%, respectively (mean +/- SEM; n = 5 experiments), of the value for control cells lacking PACAP38. This enhancement was sustained for at least 3 h after PACAP38 was removed from the perifusion medium. With PACAP treatment, interpulse secretion of LH and alpha-subunit increased gradually (P < 0.01) to 174 +/- 21% and 212 +/- 64% of the value for chambers stimulated with GnRH alone (control), respectively, whereas interpulse secretion of FSH declined (P < 0.001) to 75 +/- 7% of the control value. In contrast to the gradual effect of PACAP38 to enhance GnRH-induced hormone secretion, PACAP38 alone produced a transient burst of gonadotropin secretion. At the completion of the perifusions, total RNA was extracted and gonadotropin subunit mRNA levels were determined by Northern analysis. GnRH increased (P < 0.01) FSH beta mRNA to 438 +/- 52% of the level in cells stimulated with medium alone (control). Adding PACAP38 to the perifusion medium partially blocked (P < 0.01) the effect of GnRH (178 +/- 20% of the control value), and PACAP38 alone reduced (P < 0.01) FSH beta mRNA levels to 31 +/- 3% of the control value. By contrast, alpha-subunit mRNA levels were increased by both PACAP38 (143 +/- 4% of the control value; P < 0.01) and GnRH (121 +/- 2% of the control value; P < 0.05).(ABSTRACT TRUNCATED AT 400 WORDS)


Assuntos
Hormônio Foliculoestimulante/metabolismo , Hormônio Luteinizante/metabolismo , Neuropeptídeos/farmacologia , Adeno-Hipófise/metabolismo , RNA Mensageiro/metabolismo , Animais , Células Cultivadas , Hormônio Foliculoestimulante/genética , Hormônio Luteinizante/genética , Masculino , Neurotransmissores/farmacologia , Perfusão , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase , Adeno-Hipófise/citologia , Adeno-Hipófise/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley
4.
Endocrinology ; 138(10): 4324-9, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9322946

RESUMO

There is accumulating evidence to suggest that pituitary adenylate cyclase-activating polypeptide (PACAP) may be an important modulator ofgonadotrope function. One of the actions of PACAP identified previously is to decrease FSHbeta messenger RNA (mRNA) levels. In the present series of experiments we demonstrate that PACAP-induced suppression of FSHbeta mRNA correlates with a rise in follistatin mRNA levels in primary pituitary cell cultures. Transient transfection of gonadotrope-derived alphaT3-1 cells with a rat follistatin promoter-luciferase reporter plasmid reveals that PACAP stimulates follistatin gene transcription. PACAP stimulation of LUC activity was maximal at concentrations as low at 1 nM. Furthermore, in alphaT3-1 cells PACAP activation of the follistatin promoter appears to be via the cAMP-dependent protein kinase A pathway. Accordingly, we propose that PACAP stimulates follistatin transcription, which neutralizes activin activity and thereby reduces FSHbeta mRNA. Since PACAP and follistatin are colocalized in multiple tissues including the brain, adrenals, and gonads, our findings may reflect a broadly distributed autocrine/paracrine mechanism for modification of activin effects that is under PACAP control.


Assuntos
Hormônio Foliculoestimulante/genética , Glicoproteínas/genética , Neuropeptídeos/farmacologia , RNA Mensageiro/análise , Transcrição Gênica/efeitos dos fármacos , Glândulas Suprarrenais/química , Animais , Sequência de Bases , Química Encefálica , Células Cultivadas , AMP Cíclico/fisiologia , Proteínas Quinases Dependentes de AMP Cíclico/fisiologia , DNA/análise , DNA/química , DNA/genética , Hormônio Foliculoestimulante/análise , Subunidade beta do Hormônio Folículoestimulante , Folistatina , Glicoproteínas/análise , Masculino , Neuropeptídeos/análise , Oligonucleotídeos/análise , Oligonucleotídeos/química , Oligonucleotídeos/genética , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase , Hipófise/química , Hipófise/citologia , Plasmídeos , Reação em Cadeia da Polimerase , Regiões Promotoras Genéticas/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Testículo/química , Fatores de Tempo
5.
Endocrinology ; 133(5): 2040-8, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8404651

RESUMO

cAMP regulation of gonadotropin secretion and subunit mRNA levels was studied in pituitary cells perifused with pulses of GnRH. Pituitary cells from 7-week-old male rats castrated at 5 weeks of age were stimulated hourly for 9-24 h with 1-min pulses of GnRH, the adenylate cyclase activator forskolin, the cell-permeable cAMP analog 8-bromo-cAMP (8Br-cAMP), or control medium. Cells were also treated with the nonsteroidal antiinflammatory drug flufenamic acid, which reduces pituitary cAMP levels. During perifusion, the effluent was collected in 10-min fractions for FSH and LH assay. At the completion of perifusion, total RNA was extracted, and gonadotropin subunit mRNA levels were quantitated by Northern analysis. Continuous administration of flufenamic acid gradually reduced the amplitude of GnRH-stimulated FSH and LH pulses to nadir values of 40 +/- 4.7% and 62 +/- 12% of the control value, respectively. Flufenamic acid decreased (P < 0.05) FSH beta and alpha-subunit mRNA levels and blocked the effect of GnRH to lengthen LH beta mRNA. Pulses of forskolin or 8Br-cAMP released LH and FSH, and continuous forskolin or 8Br-cAMP potentiated the gonadotropin stimulatory effect of GnRH. Forskolin or 8Br-cAMP increased (P < 0.05) FSH beta mRNA and alpha-subunit mRNA levels when administered in pulses, but not when administered continuously, and lengthened LH beta mRNA. The Nal-Glu GnRH antagonist blocked the effects of GnRH pulses, but not the effects of 8Br-cAMP or forskolin. In conclusion, lowering intracellular cAMP levels with flufenamic acid attenuated GnRH-stimulated gonadotropin secretion, decreased alpha-subunit and FSH beta mRNA levels, and blocked the effect of GnRH to lengthen LH beta mRNA, whereas 8Br-cAMP or forskolin produced the opposite effect. These data extend previous results which suggested that cAMP modulates gonadotropin secretion and indicate that the cAMP/A-kinase pathway regulates each of the gonadotropin subunit mRNAs.


Assuntos
Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , AMP Cíclico/fisiologia , Hormônio Foliculoestimulante/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Hormônio Luteinizante/genética , RNA Mensageiro/metabolismo , 8-Bromo Monofosfato de Adenosina Cíclica/farmacologia , Animais , Células Cultivadas , Colforsina/farmacologia , Ácido Flufenâmico/farmacologia , Subunidade beta do Hormônio Folículoestimulante , Hormônio Liberador de Gonadotropina/farmacologia , Masculino , Orquiectomia , Hipófise/efeitos dos fármacos , Hipófise/metabolismo , Ratos , Ratos Sprague-Dawley
6.
J Immunol Methods ; 124(1): 17-24, 1989 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-2809226

RESUMO

Almost 90% of the sulfate groups of iota-carrageenan (CGN) was removed with acid-methanol in an attempt to obtain a product which would selectively eliminate macrophages in mice. Desulfated CGN(DS-CGN) failed to induce in vivo polyclonal antibody production in DBA/2 mice. However, the number of phagocytes in the peritoneal cavity, spleen, thymus and lymph node of DBA/2 mice was reduced stringently by DS-CGN treatment. The number of Mac-1 positive cells(macrophages) in DS-CGN-treated mice gradually decreased for at least 7 days after the last injection of DS-CGN. In contrast, the relative proportion of T and B lymphocytes in the lymphoid organs was unaffected by DS-CGN treatment. DS-CGN suppressed antibody responses to SRBC, a T cell and macrophage-dependent antigen, but no such suppressive effect was observed in the polyclonal antibody responses to LPS, a T cell and macrophage-independent B cell activator. Furthermore, the impaired SRBC antibody responses in DS-CGN-treated mice were restored following transfer of adherent cells but not T cells. These experimental results indicate that DS-CGN selectively eliminates macrophages without influencing lymphocyte function in vivo.


Assuntos
Carragenina/farmacologia , Tecido Linfoide/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Fagocitose/efeitos dos fármacos , Animais , Formação de Anticorpos/efeitos dos fármacos , Linfócitos B/efeitos dos fármacos , Linfócitos B/imunologia , Contagem de Células , Feminino , Ativação Linfocitária/efeitos dos fármacos , Tecido Linfoide/imunologia , Macrófagos/fisiologia , Camundongos , Camundongos Endogâmicos DBA , Cavidade Peritoneal , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia
7.
Immunol Lett ; 32(3): 209-14, 1992 May.
Artigo em Inglês | MEDLINE | ID: mdl-1500092

RESUMO

In general, the in vitro induction of lymphokine activated killer (LAK) cell activities by interleukin 2 (IL-2) in human peripheral blood mononuclear cells (PMNC) has been performed in an atmosphere of 5% CO2 in air (20% O2), whereas IL-2-induced LAK cell activities are considerably reduced under concentrations of 5% O2 equal to arterial blood oxygen tension (100 mmHg) and 2% O2 equal to venous blood oxygen tension (40 mmHg). Cultured cell viability, IL-2 receptor-beta expression on large granular lymphocytes (LGL), the percentage of IL-2 receptor-beta positive LGLs and cell proliferation were not affected by oxygen-limited conditions. LAK cells were induced by IL-2 over 5 days at 20% O2, at which time the LAK cells were further stimulated by IL-2 in 2% O2 and 20% O2. Under these conditions the activity of LAK cells in 2% O2 decreased day by day, while that of LAK cells induced in 20% O2 was maintained at least until day 10 of the original culture. LAK effector cell-mediated lysis was not influenced by oxygen-limited conditions. These results point to more successful applications of the combination of oxygen therapy and adoptive cellular immunotherapy in the clinic.


Assuntos
Células Matadoras Ativadas por Linfocina/imunologia , Neutrófilos/efeitos dos fármacos , Oxigênio/farmacologia , Divisão Celular/efeitos dos fármacos , Hipóxia Celular , Humanos , Interleucina-2/farmacologia , Células Matadoras Ativadas por Linfocina/efeitos dos fármacos , Oxigênio/uso terapêutico , Receptores de Interleucina-2/análise , Receptores de Interleucina-2/antagonistas & inibidores
8.
Br J Pharmacol ; 107(3): 803-7, 1992 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1282075

RESUMO

1. To explore mechanisms of urinary obstruction in benign prostatic hyperplasia (BPH), the features of contraction and relaxation in human hyperplastic and non-hyperplastic (control) prostatic tissues were investigated for beta- and alpha 1-adrenoceptors by radioligand binding and in vitro isometric tension experiments. 2. Hyperplastic and control prostatic tissues had a similar number (per mg protein) of prazosin binding sites with similar affinities. Noradrenaline (NA) induced dose-dependent contraction in both tissues. Contraction induced by either exogenous NA or transmural stimulation was inhibited by prazosin in both tissues, indicating that the same contractile mechanisms mediated by alpha 1-adrenoceptors exist in hyperplastic and control tissues. 3. The number of dihydroalprenolol (DHA) binding sites (per mg protein) was less in hyperplastic tissues than in controls, whereas the affinity to the ligand was identical in both tissues. Isoprenaline caused a marked relaxation of the tonic contraction induced by KCl in control tissues, but not in hyperplastic tissues. Propranolol enhanced exogenous NA- or transmural stimulation-induced contraction more in control tissues than in hyperplastic tissues. Both tissues, however, similarly responded to forskolin by relaxation. 4. These results indicate that decreased beta-adrenoceptor-mediated relaxation in hyperplastic prostatic tissues, which is attributable at least in part to the decreased number of beta-adrenoceptors, may play a role in the urinary obstruction of BPH in addition to mechanical compression of the urethra by the enlarged prostate.


Assuntos
Relaxamento Muscular/fisiologia , Hiperplasia Prostática/complicações , Receptores Adrenérgicos beta/fisiologia , Obstrução do Colo da Bexiga Urinária/fisiopatologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Colforsina/farmacologia , Di-Hidroalprenolol , Humanos , Técnicas In Vitro , Contração Isométrica/fisiologia , Isoproterenol/farmacologia , Cinética , Masculino , Membranas/efeitos dos fármacos , Membranas/metabolismo , Pessoa de Meia-Idade , Cloreto de Potássio/farmacologia , Prazosina/farmacologia , Propranolol/farmacologia , Ensaio Radioligante , Obstrução do Colo da Bexiga Urinária/etiologia
9.
Br J Pharmacol ; 124(6): 1175-80, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9720788

RESUMO

1. The aim of the present study was to elucidate functional differences between embryologically different portions of the posterior urethra of male rabbits in response to muscarinic acetylcholine receptor (mAChR) stimulation using in vitro isometric tension experiments and radioligand binding studies. 2. In the in vitro isometric tension experiments, carbachol, produced a dose-dependent contraction of the proximal portion under the resting state, but did not change the basal tone of the distal portion. Contraction of the proximal portion by 10(-5) M noradrenaline (NA) was dose-dependently enhanced by carbachol either in the presence or absence of NG-nitro-L-arginine (NOARG). In contrast, carbachol induced relaxation of the distal portion contracted by 10(-5) M NA, which was reversed to dose-dependent contraction in the presence of NOARG. 3. Both portions of the urethra had a similar number of [3H]-quinuclidinyl benzilate ([3H]-QNB) binding sites (195.3+/-74.1 fmols mg(-1) protein for the proximal portion and 146.5+/-8.5 fmols mg(-1) protein for the distal portion) with similar affinities (115.0+/-45.4 pM for the proximal portion and 79.9+ 2.9 pM for the distal portion). 4. The concentration-response curves to carbachol in both portions were shifted to the right in a parallel manner in the presence of pirenzepine (an M1 antagonist), 11-[[2-[(diethylamino)methyl]-1-piperidinyl] acetyl]-5, 11-dihydro-6H-pyrido-2,3-b)-(1,4)-benzodiazepin-6-one (AFDX-116, an M2 antagonist) and 4-diphenyl-acetoxy-N-methyl-piperidine (4-DAMP, an M1/M3 antagonist). The pA2 values for pirenzepine, AFDX-116 and 4-DAMP were 7.5+/-0.1, 7.2+/-0.02 and 9.3+/-0.1 respectively for the contraction of the proximal portion, and 7.2+/-0.1, 7.1+/-0.2 and 9.1+/-0.2, respectively for the relaxation of the distal portion. 5. In conclusion mAChR subtypes distribute in a similar fashion throughout the length of the male rabbit posterior urethra with the discrepant responses to carbachol attributable to the differential involvement of the NO pathway in mAChR-generated reactions.


Assuntos
Agonistas Muscarínicos/farmacologia , Receptores Muscarínicos/fisiologia , Uretra/anatomia & histologia , Animais , Carbacol/farmacologia , Técnicas In Vitro , Masculino , Nitroarginina/farmacologia , Quinuclidinil Benzilato , Coelhos , Trítio , Uretra/efeitos dos fármacos , Uretra/embriologia , Uretra/fisiologia
10.
Br J Pharmacol ; 133(1): 97-106, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11325799

RESUMO

1. We examined the effect of ischaemia on the neurogenic and nitric oxide (NO)-mediated urethral relaxation. 2. Rabbits were divided into control and urethral ischaemia (UI) groups, which was prepared by the partial occlusion of bilateral iliac arteries using blood vessel occluders. 3. Neurogenic and NO-mediated proximal urethral relaxation induced by electrical field stimulation (EFS) was greatly impaired in the UI group, while relaxation by sodium nitroprusside (SNP) as a NO donor showed no difference between the two groups. Pretreatment with L-arginine significantly improved but did not normalize the impaired relaxation in the UI group. Not only basal level, but also stimulated production of cyclic GMP with EFS, were significantly decreased in the UI group. 4. The tissue contents of N(G)-methyl-L-arginine (L-NMA) and asymmetric N(G), N(G)-dimethyl-L-arginine (ADMA) in the proximal urethra were increased following ischaemia. While L-arginine and symmetric N(G), N'(G)-dimethyl-L-arginine (SDMA) contents remained unchanged. Exogenously applied authentic L-NMA and ADMA (1 -- 100 microM) concentration-dependently inhibited the EFS-induced urethral relaxation in the control group. The inhibition with L-NMA and ADMA was undetectable in the presence of 3 mM L-arginine. 5. The Ca(2+)-dependent NOS activity in the urethra from the UI group was significantly lower than that from the control group and was not restored by an addition of 3 mM L-arginine. 6. These results suggest that the impaired neurogenic and NO-mediated urethral relaxation with ischaemia is closely related to the increased accumulation of L-NMA and ADMA and decreased NOS activity, which would result in an accelerated reduction in NO production/release.


Assuntos
Inibidores Enzimáticos/metabolismo , Isquemia/metabolismo , Relaxamento Muscular , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase/metabolismo , Uretra/metabolismo , Uretra/fisiopatologia , Animais , Arginina/análogos & derivados , Arginina/metabolismo , Arginina/farmacologia , Pressão Sanguínea , Peso Corporal , GMP Cíclico/metabolismo , Estimulação Elétrica , Inibidores Enzimáticos/farmacologia , Artéria Ilíaca/fisiologia , Técnicas In Vitro , Isquemia/enzimologia , Isquemia/fisiopatologia , Masculino , Relaxamento Muscular/efeitos dos fármacos , NG-Nitroarginina Metil Éster/metabolismo , NG-Nitroarginina Metil Éster/farmacologia , Doadores de Óxido Nítrico/farmacologia , Nitroprussiato/farmacologia , Fenilefrina/farmacologia , Coelhos , Uretra/enzimologia , Uretra/inervação
11.
Mol Cell Endocrinol ; 113(2): 123-30, 1995 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-8674819

RESUMO

Pituitary adenylate cyclase activating polypeptide (PACAP) increases glycoprotein hormone alpha-subunit mRNA levels suggesting a role for PACAP in maintaining the high levels of alpha-subunit protein characteristic of the pituitary. The present study used primary pituitary cell cultures and the alpha T3-1 pituitary cell line to investigate how PACAP affects alpha-subunit mRNA transcripts. Stimulation of cultured pituitary cells with 10 nM PACAP38, 10 nM GnRH, or the combination, for 24 h increased alpha-subunit mRNA levels 1.5-fold, whereas GnRH more effectively (P<0.01) stimulated alpha-subunit protein release than did PACAP38 (3.2- vs. 2.0-fold). alpha-Subunit mRNA levels in alphaT3-1 cells were also increased by PACAP38 and by GnRH to maximum values at 12 h (P<0.05), and alpha-subunit protein secretion rose proportionately and in parallel with alpha-subunit mRNA levels. PACAP38 was a 100-fold more potent stimulator of alpha-subunit mRNA than was VIP, and a VIP-antagonist failed to block the stimulatory effect of PACAP38, suggesting an effect via type PACAP 1 receptors. Type I receptor mRNA transcripts were identified by Northern analysis in alphaT3-1 cells. Depletion of PCK activity by PMA failed to block the stimulatory effect of PACAP38, but prevented GnRH from increasing alpha-subunit mRNA levels and alpha-subunit secretion. PACAP38, like 8Br-cAMP and forskolin, stimulated (P<0.05) luciferase (LUC) activity in alphaT3-1 cells transfected with a plasmid containing the first 846 of 180 base pairs of the 5'-flanking region of the human alpha-subunit gene linked upstream to a LUC reporter gene. Finally, experiments using the transcription inhibitor DRB reveal that PACAP does not appreciably change alpha-subunit mRNA half-life. These findings are consistent with the proposal that PACAP contributes to the high levels of alpha-subunit protein characteristic of the pituitary by activating Type I receptors and stimulating alpha-subunit gene transcription in part by the cAMP/PKA pathway.


Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Subunidade alfa de Hormônios Glicoproteicos/genética , Neuropeptídeos/farmacologia , Adeno-Hipófise/metabolismo , RNA Mensageiro/metabolismo , 8-Bromo Monofosfato de Adenosina Cíclica/farmacologia , Animais , Northern Blotting , Linhagem Celular , Células Cultivadas , Colforsina/farmacologia , Hormônio Liberador de Gonadotropina/farmacologia , Humanos , Luciferases/genética , Masculino , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase , Proteína Quinase C/metabolismo , Ratos , Transfecção
12.
Mol Cell Endocrinol ; 131(2): 241-55, 1997 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-9296383

RESUMO

Two morphologically distinct subpopulations of GT1-7 cells have been characterized and examined for their responsiveness to glucocorticoids. Type I cells have a neuronal phenotype, extending many lengthy processes, and express neuronal, but not glial, markers. Type II cells show weaker or negative immunostaining for neuronal markers and exhibit fewer processes. The effect of glucocorticoids on gonadotropin-releasing hormone (GnRH) secretion and gene expression was compared in type I and type II GT1-7 cells. For secretion studies, cells were attached to Cytodex beads and perifused with control medium or medium containing dexamethasone (dex). The high level of GnRH secreted by type I cells was slightly enhanced in the presence of dex, whereas dex rapidly and profoundly decreased the already low level of GnRH secreted by type II cells. Immunocytochemistry for GnRH showed dark reaction product in the cell bodies and processes of type I cells and little or no immunoreactivity in type II cells. Both the endogenous mouse GnRH mRNA and the transcriptional activity of a mouse GnRH promoter luciferase reporter gene plasmid were suppressed to a greater extent in type II cells than in type I. In electrophoretic mobility shift assays, there was no difference between type I and type II nuclear extracts in the pattern of protein-DNA complexes formed on two previously identified negative glucocorticoid response elements located at -237 to -201 and -184 to -150 bp of the mouse promoter. Both cell types contained glucocorticoid receptors (GR) by Western blot analysis. Cytosols from type I or type II cells were incubated with [3H]dex to obtain GR binding parameters. Binding data were consistent with a one-site model for dex binding in each case. Small differences in Kd (1.7 nM, type I; 3.1 nM, type II) or Bmax (approximately 3600 sites/cell, type I; approximately 1800 sites/cell, type II) were not likely to account for the differential sensitivity to dex treatment. In conclusion, nuclear alterations in type II cells leading to greater transcriptional susceptibility to dex, coupled with low GnRH storage levels, may be reflected in exquisite sensitivity of GnRH secretion to glucocorticoid repression. This represents the first example of a steroid hormone acting directly on GnRH-producing cells to alter GnRH secretion.


Assuntos
Expressão Gênica/efeitos dos fármacos , Glucocorticoides/farmacologia , Hormônio Liberador de Gonadotropina/genética , Neurônios/metabolismo , Animais , Western Blotting , DNA/metabolismo , Dexametasona/metabolismo , Dexametasona/farmacologia , Hormônio Liberador de Gonadotropina/metabolismo , Luciferases/genética , Camundongos , Camundongos Transgênicos , Proteínas Nucleares/metabolismo , Fosfopiruvato Hidratase/análise , Regiões Promotoras Genéticas , Proteínas Recombinantes de Fusão , Transfecção , Células Tumorais Cultivadas
13.
Eur J Endocrinol ; 140(1): 62-5, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10037254

RESUMO

A 4-year-old boy with an undescending left testis, penoscrotal hypospadia and bilateral microphthalmia was admitted to our hospital. Chromosome analysis revealed a karyotype of 46, XX del(x)(p2 2,31) and the sex-determining region of the Y chromosome (SRY) was negative. The right testis was located in the scrotum and a left cystic ovary-like gonad, a salpinx and a unicorn uterus were found in the left inguinal canal. Histologically the gonad was an ovotestis in which primordial follicles covered infantile seminiferous tubules. Microphthalmia is observed in some congenital syndromes caused by interstitial deletion of the X chromosome. This case suggested that the short arm of the X chromosome was involved in the differentiation of the gonad. Very closely located follicles and infantile seminiferous tubules indicated that induction of meiosis in the fetus was controlled by the local microenvironment in follicles and seminiferous tubules, and not by the systemic hormonal condition.


Assuntos
Transtornos do Desenvolvimento Sexual/genética , Hipospadia/genética , Microftalmia/genética , Criança , Transtornos do Desenvolvimento Sexual/cirurgia , Feminino , Deleção de Genes , Humanos , Hipospadia/cirurgia , Cariotipagem , Masculino , Microftalmia/cirurgia , Folículo Ovariano/anormalidades , Folículo Ovariano/cirurgia , Túbulos Seminíferos/anormalidades , Túbulos Seminíferos/cirurgia , Aberrações dos Cromossomos Sexuais/genética , Uretra/cirurgia
14.
J Neurotrauma ; 11(5): 613-22, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7861452

RESUMO

This report examines a modified fluid percussion device with specific improvements made to address deficiencies found in previously reported devices. These improvements include the use of a cylindrical saline reservoir made of stainless steel, placement of the reservoir in a 15-degree head-up position for the easy release of air bubbles, placement of the fluid flushing outlet and the pressure transducer close to the piston on the same plane, with both perpendicular to the direction of the piston, and adjustable reservoir volume to vary the waveform of the pressure pulse, and a metallic central injury screw secured to the animal's skull over the exposed dura. Using this device, midline fluid percussion (MFP) and lateral fluid percussion (LFP) injuries were performed in 70 rats. Histopathologic findings included diffuse axonal injury in the MFP model and cortical contusion in the LFP model. Survival rate was 41.4% in MFP animals and 100% in LFM animals when the device settings were 178 mm3 of the cylindrical reservoir and 50 degrees-60 degrees in height of the pendulum. Our results suggest that this modified fluid percussion device may offer significant improvements over previously reported fluid percussion models for use in experimental head injury.


Assuntos
Lesões Encefálicas/patologia , Percussão/instrumentação , Animais , Axônios/patologia , Concussão Encefálica/patologia , Córtex Cerebral/lesões , Córtex Cerebral/patologia , Modelos Animais de Doenças , Desenho de Equipamento , Ratos , Ratos Wistar , Cloreto de Sódio
15.
Ann N Y Acad Sci ; 416: 410-25, 1983.
Artigo em Inglês | MEDLINE | ID: mdl-6587814

RESUMO

To get reliable information about the role of charged groups of tissue components on the integrity of blood circulation, the staining and perfusion experiments of rat organs with cationic (cacodylate iron colloid) and anionic iron colloid (chondroitin iron colloid) particles were carried out. These cationic and anionic iron colloid particles are stable in a wide range of pH's. Dissociation curves of several tissue components at varied pH levels were observed for the analysis of the results obtained by histochemical observations and perfusion experiments. The results indicated that all the intra- and extracellular spaces of living tissues are surrounded by the ionized anionic groups. No ionized cationic groups were found except on the macrophage surface. The cationic iron colloid particles perfused into organs through vessels adhered to the endothelial cell surface inducing the swelling of the cells. The cationic particles invaded into surrounding tissues passing through the damaged endothelial layer, but plasma protein leakage did not occur being prevented by the newly formed fibrin-fibrinogen lining. The anionic iron colloid particles introduced into vessels did not adhere to blood vessel walls but were taken by reticuloendothelial cells or macrophages. The importance of the ionized anionic groups of proteins on the endothelial cell surface and surrounding tissues for the integrity of blood vessel function was stressed.


Assuntos
Vasos Sanguíneos/fisiologia , Animais , Adesão Celular , Coloides , Histocitoquímica , Concentração de Íons de Hidrogênio , Ferro/metabolismo , Rim/citologia , Fígado/citologia , Substâncias Macromoleculares , Microscopia Eletrônica , Microscopia Eletrônica de Varredura , Perfusão , Permeabilidade , Ratos , Ratos Endogâmicos , Propriedades de Superfície
16.
Cancer Chemother Pharmacol ; 23 Suppl: S33-6, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2538263

RESUMO

The therapeutic results of Lp-TAE (transcatheter arterial embolization with Gelfoam particles preceded by the infusion of a mixture of lipiodol and an anticancer drug via the proper hepatic artery) were evaluated in hepatocellular carcinomas (523 non-resected and 24 resected cases). Excellent therapeutic effects were confirmed not only for the main tumor but also for the daughter nodules by a histological examination of the liver tissues resected after Lp-TAE. The cumulative 1-year, 2-year and 3-year survival rates in the 523 non-resected cases were 60.4%, 42.9% and 28.0% respectively. These survival rates were all higher than those achieved by Gelfoam TAE. The above results suggest the usefulness of Lp-TAE in the treatment of hepatocellular carcinoma.


Assuntos
Carcinoma Hepatocelular/terapia , Doxorrubicina/administração & dosagem , Embolização Terapêutica , Óleo Iodado/administração & dosagem , Neoplasias Hepáticas/terapia , Mitomicinas/administração & dosagem , Carcinoma Hepatocelular/mortalidade , Cateterismo Periférico , Artéria Hepática , Humanos , Neoplasias Hepáticas/mortalidade , Mitomicina
17.
J Atheroscler Thromb ; 2(1): 66-9, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-9225211

RESUMO

A 41-year-old female patient with muscle dystrophy, hepatosplenomegaly and tendinous xanthoma showed mild hypertriglyceridemia. The lipoprotein profile in blood showed increases in triglycerides in VLDL and LDL, and a marked decrease of cholesterol in HDL. Chylomicronemia was found, but was not severe. Both lipoprotein lipase and hepatic triglyceride lipase activities were reduced to a level that was only a few percent of the control. Immunoblotting study revealed that the IgG autoantibody in her serum was apparently reactable with hepatic triglyceride lipase and weakly with lipoprotein lipase. Hypertriglyceridemia in this patient is suggested to be due to the autoantibody to these lipases.


Assuntos
Autoanticorpos/imunologia , Hipertrigliceridemia/imunologia , Lipase Lipoproteica/imunologia , Adulto , Feminino , Humanos , Hipertrigliceridemia/sangue , Imunoglobulina G/imunologia , Lipoproteínas/sangue
18.
J Gastroenterol ; 29(1): 80-3, 1994 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8199700

RESUMO

The spontaneous passage of colon cast from a 76-year-old Japanese female patient is reported. Macroscopically, the colon case was shaped like the airbladder of a fish. Histopathologically, the cast consisted of degenerated colonal mucosa, including glands. No inflammatory reaction was apparent. The patient lacked any evidence of abdominal aneurysm. Since there have been only five reported cases of colon cast in the literature, and since in all of those association with abdominal aneurysms was always described, the present study represents the first report demonstrating the formation of a colon cast in the absence of associated abdominal aneurysm. However, the patient was found to exhibit several risk factors for ischemic colitis, such as arteriosclerosis on the wall of the abdominal aorta, chronic constipation, and colonic stenosis. Her colonal mucosal surface, indeed, suggested ischemic colitis. This case report, therefore, indicates that ischemic colitis, due to various causes, may be responsible for the formation of colon casts, and that the presence of an abdominal aneurysm is not necessarily a prerequisite for colon cast formation. This report may contribute to a better understanding of the pathogenesis of colon casts.


Assuntos
Aneurisma da Aorta Abdominal/complicações , Colite Isquêmica/patologia , Colo/patologia , Mucosa Intestinal/patologia , Idoso , Colite Isquêmica/complicações , Feminino , Humanos
19.
J Gastroenterol ; 34(1): 75-82, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10204614

RESUMO

Decreased effective circulating blood volume is an important factor in ascites formation in liver cirrhosis. We designed a "body compression" apparatus as a means to restore effective blood volume and investigated its effectiveness in reducing ascites formation in cirrhotics in terms of its effect on parameters of ascites formation noted below. The subjects, eight cirrhotics with ascites and eight cirrhotics without ascites were given spironolactone (50-75 mg/day) and furosemide (40-80 mg/day) while they received a diet containing 85 mEq of sodium per day. All four limbs and the lower abdomen were compressed with constant pressure [height (cm) divided by 13.6 mmHg] once, for 3h, using stroke rehabilitation splints, while patients lay supine. In cirrhotics both with and without ascites, urine volume, urinary sodium excretion, and creatinine clearance during the body compression were greater than values during control (non-compression) periods (urine volume, means 285 vs 169 ml/3h; P < 0.001, urinary sodium excretion 15.8 vs 9.5 mEq/3h; p < 0.001, creatinine clearance 74 vs 59 ml/min, P < 0.001, respectively). The increased basal plasma renin activity, angiotensin II, aldosterone, and norepinephrine levels in all cirrhotics were significantly decreased by the body compression. In another group of six cirrhotics who received no diuretics or albumin, repeat body compression alleviated ascites in three with well preserved renal function, but was ineffective in three with markedly impaired renal function. These results suggest that the improvement in renal function brought about by the body compression is attributable to an increase in effective circulating blood volume. This maneuver may be a useful complementary therapy in patients with cirrhotic ascites with well preserved renal function.


Assuntos
Ascite/prevenção & controle , Trajes Gravitacionais , Cirrose Hepática/complicações , Adulto , Idoso , Ascite/etiologia , Ascite/fisiopatologia , Volume Sanguíneo , Feminino , Deslocamentos de Líquidos Corporais , Seguimentos , Humanos , Testes de Função Renal , Cirrose Hepática/fisiopatologia , Cirrose Hepática/terapia , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Pressão , Resultado do Tratamento
20.
Life Sci ; 56(13): 1103-11, 1995 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-9001444

RESUMO

The effects of pituitary adenylate cyclase activating polypeptide (PACAP) administered intermittently on gonadotropin secretion and subunit mRNA levels in anterior pituitary cells from 7wk old intact and orchidectomized rats were studied. Cells were perifused for 9 h with hourly pulses of 2.5 nM GnRH or 10 nM PACAP, or with medium alone. Pulsatile PACAP initiated episodes of LH, FSH and alpha-subunit secretion, but was much less effective than GnRH. Responsiveness declined with repeated pulses of PACAP, although interpulse secretion increased gradually throughout the experiment. PACAP was a slightly more effective stimulator of LH release by pituitary cells from castrated than intact rats. At the completion of perifusion, pituitary RNA from castrated rats was extracted for measurement of gonadotropin subunit mRNA levels. Pulsatile PACAP stimulated alpha-subunit and LHbeta mRNA levels but did not affect FSHbeta mRNA. By contrast, continuous PACAP increased alpha-subunit mRNA levels, but suppressed FSHbeta mRNA without affecting LHbeta mRNA. We conclude that pulsatile PACAP is a relatively ineffective stimulator of gonadotropin secretion when administered alone, and regulates gonadotopin subunit gene expression quite differently than continuous PACAP. We propose that the mode of PACAP secretion in vivo may be a determinant of the differential expression of the gonadotropin subunit genes.


Assuntos
Gonadotropinas/metabolismo , Neuropeptídeos/farmacologia , Neurotransmissores/farmacologia , Hipófise/efeitos dos fármacos , RNA Mensageiro/análise , Animais , Northern Blotting , Células Cultivadas , Hormônio Foliculoestimulante/genética , Hormônio Foliculoestimulante/metabolismo , Regulação da Expressão Gênica , Subunidade alfa de Hormônios Glicoproteicos/genética , Subunidade alfa de Hormônios Glicoproteicos/metabolismo , Gonadotropinas/genética , Hormônio Luteinizante/genética , Hormônio Luteinizante/metabolismo , Masculino , Neuropeptídeos/administração & dosagem , Neurotransmissores/administração & dosagem , Orquiectomia , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase , Hipófise/citologia , Hipófise/metabolismo , Fluxo Pulsátil , Ratos , Ratos Sprague-Dawley
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