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1.
Phys Rev Lett ; 125(11): 111103, 2020 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-32975983

RESUMO

To understand the nature of the brightest γ-ray binary system LS 5039, hard x-ray data of the object, taken with the Suzaku and NuSTAR observatories in 2007 and 2016, respectively, were analyzed. The two data sets jointly gave tentative evidence for a hard x-ray periodicity, with a period of ∼9 s and a period increase rate by ∼3×10^{-10} s s^{-1}. Therefore, the compact object in LS 5039 is inferred to be a rotating neutron star, rather than a black hole. Furthermore, several lines of arguments suggest that this object has a magnetic field of several times ∼10^{10} T, two orders of magnitude higher than those of typical neutron stars. The object is hence suggested to be a magnetar, which would be the first to be found in a binary. The results also suggest that the highly efficient particle acceleration process, known to be operating in LS 5039, emerges through interactions between dense stellar winds from the massive primary star, and ultrastrong magnetic fields of the magnetar.

2.
Mol Psychiatry ; 23(3): 639-647, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28115744

RESUMO

Genome-wide association studies (GWASs) have identified several susceptibility loci for bipolar disorder (BD) and shown that the genetic architecture of BD can be explained by polygenicity, with numerous variants contributing to BD. In the present GWAS (Phase I/II), which included 2964 BD and 61 887 control subjects from the Japanese population, we detected a novel susceptibility locus at 11q12.2 (rs28456, P=6.4 × 10-9), a region known to contain regulatory genes for plasma lipid levels (FADS1/2/3). A subsequent meta-analysis of Phase I/II and the Psychiatric GWAS Consortium for BD (PGC-BD) identified another novel BD gene, NFIX (Pbest=5.8 × 10-10), and supported three regions previously implicated in BD susceptibility: MAD1L1 (Pbest=1.9 × 10-9), TRANK1 (Pbest=2.1 × 10-9) and ODZ4 (Pbest=3.3 × 10-9). Polygenicity of BD within Japanese and trans-European-Japanese populations was assessed with risk profile score analysis. We detected higher scores in BD cases both within (Phase I/II) and across populations (Phase I/II and PGC-BD). These were defined by (1) Phase II as discovery and Phase I as target, or vice versa (for 'within Japanese comparisons', Pbest~10-29, R2~2%), and (2) European PGC-BD as discovery and Japanese BD (Phase I/II) as target (for 'trans-European-Japanese comparison,' Pbest~10-13, R2~0.27%). This 'trans population' effect was supported by estimation of the genetic correlation using the effect size based on each population (liability estimates~0.7). These results indicate that (1) two novel and three previously implicated loci are significantly associated with BD and that (2) BD 'risk' effect are shared between Japanese and European populations.


Assuntos
Transtorno Bipolar/genética , Adulto , Proteínas de Ciclo Celular/genética , Citocinas/genética , Dessaturase de Ácido Graxo Delta-5 , Ácidos Graxos Dessaturases/genética , Feminino , Predisposição Genética para Doença/genética , Estudo de Associação Genômica Ampla , Humanos , Japão/epidemiologia , Masculino , Glicoproteínas de Membrana/genética , Pessoa de Meia-Idade , Herança Multifatorial/genética , Fatores de Transcrição NFI/genética , Proteínas Nucleares/genética , Polimorfismo de Nucleotídeo Único/genética
3.
Sci Rep ; 14(1): 2573, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38336981

RESUMO

To detect and track structural changes in atomic nuclei, the systematic study of nuclear levels with firm spin-parity assignments is important. While linear polarization measurements have been applied to determine the electromagnetic character of gamma-ray transitions, the applicable range is strongly limited due to the low efficiency of the detection system. The multi-layer Cadmium-Telluride (CdTe) Compton camera can be a state-of-the-art gamma-ray polarimeter for nuclear spectroscopy with the high position sensitivity and the detection efficiency. We demonstrated the capability to operate this detector as a reliable gamma-ray polarimeter by using polarized 847-keV gamma rays produced by the [Formula: see text]([Formula: see text]) reaction. By combining the experimental data and simulated calculations, the modulation curve for the gamma ray was successfully obtained. A remarkably high polarization sensitivity was achieved, compatible with a reasonable detection efficiency. Based on the obtained results, a possible future gamma-ray polarimetery is discussed.

4.
Phys Rev E ; 105(2-2): 025203, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35291161

RESUMO

We present an experimental method to generate quasiperpendicular supercritical magnetized collisionless shocks. In our experiment, ambient nitrogen (N) plasma is at rest and well magnetized, and it has uniform mass density. The plasma is pushed by laser-driven ablation aluminum (Al) plasma. Streaked optical pyrometry and spatially resolved laser collective Thomson scattering clarify structures of plasma density and temperatures, which are compared with one-dimensional particle-in-cell simulations. It is indicated that just after the laser irradiation, the Al plasma is magnetized by a self-generated Biermann battery field, and the plasma slaps the incident N plasma. The compressed external field in the N plasma reflects N ions, leading to counterstreaming magnetized N flows. Namely, we identify the edge of the reflected N ions. Such interacting plasmas form a magnetized collisionless shock.

5.
Minim Invasive Neurosurg ; 53(2): 77-9, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20533139

RESUMO

INTRODUCTION: The aim of this study is to describe the case of a cavernous hemangioma extending from the orbital apex to the pterygopalatine fossa that was completely removed via an endoscopic transnasal approach. CASE REPORT: We report the case of a 48-year-old man who presented with right hemianopsia of the left eye. MRI revealed a 1.5 x 1.1 cm mass lesion extending from the infero-medial part of the left orbital apex to the pterygopalatine fossa. Removal of the lesion was performed via the endoscopic transnasal approach. Using this approach, a wide operative view of the entire extent of the lesion from the optic canal to the orbital apex and the pterygopalatine fossa was obtained, and complete removal of the lesion was performed safely. The pathological diagnosis was cavernous hemangioma. CONCLUSION: The endoscopic transnasal approach is a safe, effective, and less invasive therapeutic modality for the removal of lesions extending from the infero-medial part of the left orbital apex to the pterygopalatine fossa. With appropriate patient selection, this approach improves access and visualization, and it enables performance of operative procedures with much less risk than the conventional microscopic transcranial or transfacial approaches.


Assuntos
Hemangioma/cirurgia , Órbita/cirurgia , Neoplasias Orbitárias/cirurgia , Endoscopia , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
7.
Acta Neurol Scand ; 118(1): 54-9, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18261166

RESUMO

BACKGROUND: Cerebral vasospasm following subarachnoid hemorrhage (SAH) is a significant cause of morbidity and mortality and recent studies indicate that Rho-kinase plays an important role in the occurrence of such cerebral vasospasm. Eicosapentaenoic acid (EPA), an n-3 polyunsaturated fatty acid, inhibits sphingosylphosphorylcholine (SPC)-induced Rho-kinase activation in vitro, so this study examined whether EPA prevented cerebral vasospasm occurrence after SAH in patients. METHODS: The trial population was 101 patients with SAH subjected to craniotomy and clip application. EPA was orally administered at a daily dose of 1800 mg EPA from day 4 to day 14 to 73 patients; the other 28 constituted the control group, receiving no EPA. RESULTS: EPA significantly curtailed both the occurrence of symptomatic vasospasm (14% EPA group, 36% control, P = 0.019) and of cerebral infarction because of cerebral vasospasm (4% EPA group, 29% control, P = 0.001). Moreover, the percentage of patients with a clinically good outcome was significantly higher in the EPA group (85%, P = 0.022) than in control (64%); there were no deaths in the EPA group but three (11%) in control (P = 0.020). CONCLUSION: These findings suggest EPA inhibits symptomatic cerebral vasospasm and cerebral infarction after SAH and also improves clinical prognosis.


Assuntos
Aneurisma Roto/terapia , Ácido Eicosapentaenoico/análogos & derivados , Aneurisma Intracraniano/terapia , Inibidores da Agregação Plaquetária/uso terapêutico , Hemorragia Subaracnóidea/terapia , Vasoespasmo Intracraniano/prevenção & controle , Adulto , Idoso , Idoso de 80 Anos ou mais , Aneurisma Roto/complicações , Aneurisma Roto/diagnóstico , Ácido Eicosapentaenoico/uso terapêutico , Feminino , Seguimentos , Humanos , Aneurisma Intracraniano/complicações , Aneurisma Intracraniano/diagnóstico , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Hemorragia Subaracnóidea/complicações , Hemorragia Subaracnóidea/diagnóstico , Resultado do Tratamento , Vasoespasmo Intracraniano/diagnóstico , Vasoespasmo Intracraniano/etiologia
8.
Acta Neurochir (Wien) ; 150(1): 31-9; discussion 39, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18058058

RESUMO

BACKGROUND: To evaluate our decision policy based on vertical aneurysm projection for selecting the side of the pterional approach for the surgical treatment of anterior communicating artery aneurysms. METHODS: Inferiorly projecting aneurysms were treated through the dominant A1 side, and superiorly projecting aneurysms were treated through the side of aneurysm fundus projection. We analysed postoperative outcome and surgical complications, and the correlations between the anatomical factors such as position (high or low), projection (dorsal or anterior), and the plane containing both A2 vessels (open A2 plane defined as the A2 of the approach side located more posteriorly than the contralateral A2; closed A2 plane as the ipsilateral A2 located more anteriorly than the contralateral A2), to assess the surgical requirements of approaches in patients with superiorly projecting aneurysms. FINDINGS: A favorable outcome was achieved in 95.1% of patients with inferior type aneurysms and 85.2% of patients with superior type aneurysms (P = 0.088). Surgical complications occurred in 8.9% of patients with inferior type aneurysms and 17.9% with superior type aneurysms. However, there was a distinct group of patients with superior type aneurysms characterised by a closed A2 plane, in which the ipsilateral A2 was located anterior to the contralateral A2, in whom the approach toward the neck was significantly more difficult, requiring A2 displacement or gyrus aspiration, and resulting in a neck remnant and more surgical complications such as vascular injury or cerebral contusion. This group also had a significantly high correlation with high position and dorsal projection of aneurysms causing more difficult dissection. CONCLUSIONS: This policy provided good postoperative outcomes. However, use of skull base techniques or the interhemispheric approach, instead of the normal pterional approach, may further improve the postoperative outcome for closed A2 plane aneurysms.


Assuntos
Aneurisma Roto/cirurgia , Aneurisma Intracraniano/cirurgia , Procedimentos Neurocirúrgicos/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Angiografia , Feminino , Escala de Resultado de Glasgow , Humanos , Aneurisma Intracraniano/classificação , Aneurisma Intracraniano/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Análise de Regressão , Resultado do Tratamento
9.
J Hand Surg Eur Vol ; 43(3): 324-330, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28462679

RESUMO

Boutonnière deformity of the thumb without rheumatoid arthritis or trauma is not widely recognised. This study aimed to investigate its prevalence, relation to sex and age, and identifying factors associated with the extensor mechanism using ultrasonography. We examined 248 thumbs from 127 participants who were asymptomatic for hand disorders and had no history of hand injury. Boutonnière deformity was identified in 20 thumbs of 17 participants and was significantly more prevalent among elderly participants than among young participants. No significant differences in sex or hand dominance were noted. The deformity had a significant effect on range of motion and grip and pinch strengths. The extensor pollicis brevis (EPB) tendon was significantly narrower in affected thumbs than in non-affected thumbs. The prevalence of boutonnière deformity without rheumatoid arthritis or trauma was 13%, and the deformity was associated with advanced age and a narrow EPB tendon. LEVEL OF EVIDENCE: III.


Assuntos
Deformidades Adquiridas da Mão/epidemiologia , Polegar/anormalidades , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Deformidades Adquiridas da Mão/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos , Polegar/diagnóstico por imagem , Ultrassonografia/métodos
10.
Diabetes Care ; 15(11): 1517-21, 1992 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1468279

RESUMO

OBJECTIVE: To study the possible contribution of a B-cell defect in the development of glucose intolerance in nonobese subjects. RESEARCH DESIGN AND METHODS: There were 41 normal, nondiabetic subjects; 18 subjects with IGT; and 21 patients with NIDDM. All subjects were nonobese (BMI < 27 kg/m2). Insulin secretory responses to an OGTT, IVGTT, and GST were studied. RESULTS: Early-phase insulin responses to OGTT and IVGTT were decreased in subjects with IGT to levels comparable with those in NIDDM patients, whereas the response to GST was preserved in the subjects with IGT compared with NIDDM patients. The insulinogenic index of OGTT correlated well (r = 0.78) with early-phase insulin response to IVGTT, suggesting that the insulinogenic index in OGTT is related to the early-phase insulin response to IVGTT in nonobese subjects. CONCLUSIONS: Impaired early-phase insulin response to glucose was associated with mild glucose intolerance, suggesting the importance of impaired insulin secretion in the development of glucose intolerance in nonobese subjects.


Assuntos
Glicemia/metabolismo , Diabetes Mellitus Tipo 2/sangue , Teste de Tolerância a Glucose , Hiperglicemia/sangue , Insulina/sangue , Diabetes Mellitus Tipo 2/fisiopatologia , Glucagon , Humanos , Hiperglicemia/fisiopatologia , Insulina/metabolismo , Secreção de Insulina , Valores de Referência
11.
Am J Clin Nutr ; 52(4): 689-93, 1990 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2403061

RESUMO

To investigate how urinary excretion rates (UERs) of maltose and glucose are determined after intravenous maltose infusion, maltose and glucose solutions were infused at various rates and the relationships between UERs of maltose and glucose and their plasma concentrations were examined. Results showed the existence of a threshold plasma maltose concentration for the urinary excretions of maltose and glucose and the existence of a maximum rate of urinary glucose excretion after maltose infusion. Elevation of plasma glucose concentration by simultaneous glucose infusion increased urinary glucose excretion but did not increase urinary maltose excretion; the relationship between plasma total sugar concentration and urinary total sugar excretion was unchanged. Results suggest that maltose administered intravenously is hydrolyzed to glucose by maltase in renal tubules and reabsorbed as glucose competitively with glucose derived from plasma and that the maximum utilization of intravenously infused maltose is determined by the tubular glucose reabsorption capacity.


Assuntos
Túbulos Renais/metabolismo , Maltose/metabolismo , Adulto , Glicemia/metabolismo , Carboidratos/urina , Limiar Diferencial , Glicosúria/urina , Humanos , Injeções Intravenosas , Glomérulos Renais/metabolismo , Masculino , Maltose/sangue , Maltose/urina , Concentração Osmolar
12.
Am J Med Genet ; 48(3): 151-5, 1993 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-8291569

RESUMO

To test a hypothesis that the pseudoautosomal region of the sex chromosomes contributes to the pathogenesis of schizophrenia, we carried out the following studies: First, the sex concordant rates of 77 schizophrenic sibpairs were examined. Secondly, 46 schizophrenic patients and 150 healthy controls were tested for association with DXYS17, DXYS20, DXYS28, and MIC2 in the pseudoautosomal region. Sex concordant rates in sibpairs with schizophrenia were not higher than would be expected by chance. No significant associations were found between four DNA markers we tested and schizophrenia. These results did not support the hypothesis; however, linkage disequilibrium can only be detected if the marker and trait loci are located close enough. Linkage analyses in multiplex families need to be carried out before ruling out this region as a location for a gene for schizophrenia.


Assuntos
Aberrações Cromossômicas/genética , Esquizofrenia/genética , Transtornos Cromossômicos , Feminino , Marcadores Genéticos , Humanos , Masculino , Linhagem
13.
Am J Med Genet ; 48(2): 87-9, 1993 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-8103293

RESUMO

Sixty-eight patients with bipolar affective disorder and 88 controls were investigated for genetic association of tyrosine hydroxylase (TH) restriction fragment length polymorphisms (RFLPs). No significant association between bipolar affective disorder and TH was found. Thus the hypothesis that TH is involved in the pathogenesis of bipolar affective disorder was not supported.


Assuntos
Transtorno Bipolar/genética , Cromossomos Humanos Par 11 , Tirosina 3-Mono-Oxigenase/genética , Adulto , Transtorno Bipolar/enzimologia , Estudos de Casos e Controles , Feminino , Frequência do Gene , Ligação Genética , Marcadores Genéticos , Humanos , Japão , Masculino , Polimorfismo de Fragmento de Restrição
14.
Am J Med Genet ; 67(1): 103-5, 1996 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-8678105

RESUMO

Sixty-two patients with schizophrenia and 96 normal controls were investigated for genetic association with restriction fragment length polymorphisms (RFLPs) in the serotonin receptor genes. A positive association between the serotonin 2A receptor gene (HTR2A) and schizophrenia was found, but not between schizophrenia and the serotonin 1A receptor gene. The positive association we report here would suggest that the DNA region with susceptibility to schizophrenia lies in the HTR2A on the long arm of chromosomes 13.


Assuntos
Polimorfismo de Fragmento de Restrição , Receptores de Serotonina/genética , Esquizofrenia/genética , Adulto , Sequência de Bases , DNA/genética , Primers do DNA , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Receptor 5-HT2A de Serotonina
15.
Am J Med Genet ; 74(2): 179-82, 1997 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-9129720

RESUMO

We examined the allelic association between the dopamine D2 receptor (DRD2) gene and alcoholism in 100 biologically unrelated Japanese alcoholics and 93 unrelated controls. Genomic DNA was prepared from peripheral white blood cells using the phenol-chloroform method. A 310-bp region surrounding the TaqA site at the DRD2 locus was amplified by polymerase chain reaction (PCR), and the PCR product was incubated with TaqI. The A1 allele remained intact while the A2 allele was cut. The frequency of the A1/A1 genotype and the frequency of the A1 allele were higher in early-onset alcoholics than in controls, P < 0.05 and P < 0.01, respectively. Moreover, the frequency of the A1/A1 genotype and the frequency of the A1 allele were higher in early-onset alcoholics with family histories of alcohol dependence than in controls, P < 0.01 and P < 0.01, respectively. The results indicate that the DRD2 gene is associated with susceptibility to early-onset alcoholism, and that each additional A1 allele shifts onset of alcoholism to an earlier age.


Assuntos
Alcoolismo/genética , Receptores de Dopamina D2/genética , Adulto , Idade de Início , Alelos , Feminino , Dosagem de Genes , Genótipo , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Polimorfismo de Fragmento de Restrição
16.
Schizophr Res ; 6(1): 9-13, 1991 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1786238

RESUMO

It has been reported that the amplitude of P300 is low in schizophrenic patients and high risk children. We recorded P300 components of the event-related potentials in first degree relatives of schizophrenic propositi who were considered to be over the age limit of the risk period for manifestation of schizophrenia and compared them with those of schizophrenic patients and controls. Both the first degree relatives and the schizophrenic patients showed lower P300 amplitude than the controls. There was no significant difference between the first degree relatives and schizophrenic patients in the P300 amplitude. These results would indicate that a low P300 amplitude is a trait marker for schizophrenia.


Assuntos
Nível de Alerta/genética , Atenção , Eletroencefalografia , Esquizofrenia/genética , Psicologia do Esquizofrênico , Adulto , Potenciais Evocados Auditivos/genética , Potenciais Evocados Visuais/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Esquizofrenia/diagnóstico
17.
Virchows Arch ; 433(4): 349-57, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9808437

RESUMO

The angiotensin II type 1a (AT1a) receptor is the major receptor effecting the multiple actions of angiotensin II on the cardiovascular system. It is expressed abundantly in the glomerular mesangial cells of the kidney. We investigated glomerular changes in null mutant mice minus the AT1a receptor gene to gain an understanding of the in vivo action of angiotensin II via AT1a on the mesangium. Morphological observations and morphometric analysis revealed that the glomerular volume was greatly increased owing to the expansion of the mesangial area, which contained fluid-filled spaces with a small amount of fibrillar components. The mesangial cells lost contact with each other and with the perimesangial area of the glomerular basement membrane (GBM), so that the glomerular capillary neck was greatly widened. These findings suggest a defect of the anchoring function of mesangial cells resulting from some abnormality in mesangial matrix formation. We conclude that angiotensin II has an important role in the structural and functional maintenance of the mesangium via the AT1a receptor, especially by reinforcing the connection between mesangial cells and GBM via the mesangial matrix.


Assuntos
Angiotensina II/fisiologia , Mesângio Glomerular/fisiologia , Receptores de Angiotensina/genética , Animais , Membrana Basal/ultraestrutura , Matriz Extracelular/fisiologia , Matriz Extracelular/ultraestrutura , Deleção de Genes , Mesângio Glomerular/ultraestrutura , Processamento de Imagem Assistida por Computador , Glomérulos Renais/ultraestrutura , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Microscopia Eletrônica , Receptor Tipo 1 de Angiotensina , Receptores de Angiotensina/metabolismo
18.
Neuroreport ; 9(17): 3791-6, 1998 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-9875706

RESUMO

Tumor necrosis factor-alpha (TNFalpha) was infused into the subarachnoid space of the rat rostral basal forebrain, which was previously defined as a prostaglandin (PG) D2-sensitive, sleep-promoting zone. TNFalpha increased the amount of slow-wave sleep (SWS), decreased that of paradoxical sleep (PS), and caused fever and anorexia. The TNFalpha-induced SWS enhancement, fever and anorexia were all blocked by co-infusion of diclofenac, a non-selective cyclooxygenase (COX) inhibitor, and by pretreatment with NS-398, a COX-2-specific inhibitor. In striking contrast, the TNFalpha-induced suppression of PS was not affected by the inhibitors. These results indicate that COX-2-mediated hyperproduction of PGs is critically involved in the enhancement of SWS, fever, and anorexia but not in the suppression of PS, caused by TNFalpha infused into the PGD2-sensitive zone.


Assuntos
Isoenzimas/fisiologia , Prostaglandina-Endoperóxido Sintases/fisiologia , Sono/efeitos dos fármacos , Fator de Necrose Tumoral alfa/farmacologia , Animais , Ciclo-Oxigenase 2 , Inibidores de Ciclo-Oxigenase 2 , Inibidores de Ciclo-Oxigenase/farmacologia , Diclofenaco/farmacologia , Interleucina-1/farmacologia , Masculino , Prosencéfalo/efeitos dos fármacos , Prostaglandina D2/farmacologia , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes/farmacologia
19.
Neuroreport ; 11(10): 2127-31, 2000 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-10923657

RESUMO

Prostaglandin (PG) E2 reportedly augmented wakefulness when continuously infused into the third ventricle of the rat brain, whereas it promoted sleep when continuously infused into the subarachnoid space of the ventral surface zone of the rostral basal forebrain, which was designated previously as a PGD2-sensitive sleep-promoting zone (PGD2-SZ). In the present study, we investigated the effects of PGE (EP)-receptor agonists on sleep-wakefulness activities by infusing agonists into the third ventricle or into the subarachnoid space of the PGD2-SZ. Our results indicated that the waking effect is mediated by EP1 and EP2 receptors situating around the third ventricle, whereas the sleep-promoting effect is brought about mainly through activation of EP4 receptors located at or near the subarachnoid space of the PGD2-SZ.


Assuntos
Prosencéfalo/fisiologia , Prostaglandina D2/farmacologia , Receptores de Prostaglandina E/fisiologia , Sono/fisiologia , Animais , Ritmo Circadiano , Infusões Parenterais , Masculino , Prosencéfalo/efeitos dos fármacos , Prostaglandina D2/administração & dosagem , Ratos , Ratos Sprague-Dawley , Receptores de Prostaglandina E/agonistas , Receptores de Prostaglandina E/antagonistas & inibidores , Receptores de Prostaglandina E Subtipo EP1 , Receptores de Prostaglandina E Subtipo EP2 , Receptores de Prostaglandina E Subtipo EP4 , Sono/efeitos dos fármacos , Vigília/efeitos dos fármacos
20.
Kidney Int Suppl ; 63: S201-4, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9407459

RESUMO

To localize angiotensin II type 1a (AT-1a) receptor and to reveal the physiological roles of angiotensin II in the renal microcirculation, we investigated the AT-1a gene deficient mice, generated by a targeted replacement of the AT-1a receptor loci by the lacZ gene (Sugaya et al, J Biol Chem 270: 18719, 1995). Immunohistochemical localization of beta-galactosidase was performed in the heterozygous mutant mice to reveal the expression sites of AT-1a. The AT-1a receptor (that is, beta-galactosidase) was expressed both in the afferent and efferent arteriolar smooth muscles and also in the mesangial cells. The effect of angiotensin II on glomerular arterioles was directly observed using the hydronephrotic mice. Angiotensin II similarly constricted both the afferent and efferent arterioles in the wild-type and heterozygous mutant mice in a dose-dependent manner. This constriction was completely abolished by an AT-1 antagonist, CV-11974. In the homozygous null mutant mice, however, angiotensin II did not affect the arterioles at all. Electron microscopic studies revealed that the mesangial cells made contact with the glomerular basement membrane (GBM) at the capillary neck and also with each other in the wild-type mice. However, in the homozygous null mutant mice, the mesangial cells lost the contact either with GBM or with each other and thus the capillary neck became remarkably wider. The mesangial matrix area appeared loose and enlarged, suggesting impaired mesangial matrix formation. In conclusion, via the AT-1a receptor, angiotensin II equally constricts both the afferent and efferent arterioles and plays an essential role in maintaining the normal glomerular function and structure.


Assuntos
Angiotensina II/metabolismo , Receptores de Angiotensina/metabolismo , Circulação Renal/efeitos dos fármacos , Angiotensina II/deficiência , Angiotensina II/farmacologia , Animais , Arteríolas/efeitos dos fármacos , Mesângio Glomerular/citologia , Mesângio Glomerular/efeitos dos fármacos , Mesângio Glomerular/metabolismo , Hidronefrose/genética , Hidronefrose/patologia , Imuno-Histoquímica , Camundongos , Microcirculação/efeitos dos fármacos , Receptores de Angiotensina/efeitos dos fármacos , Receptores de Angiotensina/genética , beta-Galactosidase/metabolismo
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