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1.
J Neonatal Perinatal Med ; 14(2): 177-182, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33074195

RESUMO

BACKGROUND: The fetal brain is vulnerable to severe and sustained hypoxia during and after birth, which can lead to hypoxic-ischemic encephalopathy (HIE). HIE is characterized by clinical and laboratory evidence of acute or subacute brain injury. The role of cytokines in the pathogenesis of brain injury and their relation to neurological outcomes of asphyxiated neonates are not fully understood. In this study, we investigated cytokine profile related to cerebral palsy (CP) with neonatal hypoxic ischemic encephalopathy (HIE) and HIE severity. METHODS: Eligible subjects were HIE newborns with a gestational age between 36 and 42 weeks. We included newborns who was born at our NICU and did not admit to NICU as healthy controls. The study comprised 52 newborns, including 13 with mild to severe HIE and 39 healthy control. Serum cytokine profiles were performed using a LUMINEX cytokine kit (R&D Systems). RESULTS: VEGF, MCP-1, IL-15, IL-12p70, IL-12p40, IL-1Ra, IL-2, IL-6, IL-7, IL-8, IL-10, IFN-γ, G-CSF and eotaxin in the HIE patients were significantly increased compared with the healthy neonates. In the subgroup analysis, IL-6 and G-CSF were significantly increased in CP infants (n = 5) compared with non-CP infants (n = 8). Five and eight HIE patients were classified into the mild HIE and moderate-severe HIE groups, respectively. IL-6, 10, 1Ra, and G-CSF in the moderate-severe HIE group were significantly higher than those in the mild HIE group. CONCLUSION: We demonstrated that higher serum IL-6 and G-CSF at birth in HIE patients were associated with CP and moderate-severe HIE.


Assuntos
Citocinas/sangue , Hipóxia-Isquemia Encefálica/diagnóstico , Hipóxia-Isquemia Encefálica/imunologia , Índice de Gravidade de Doença , Biomarcadores/sangue , Estudos de Casos e Controles , Feminino , Idade Gestacional , Humanos , Lactente , Recém-Nascido , Masculino , Triagem Neonatal , Exame Neurológico
2.
Eur J Biochem ; 228(3): 899-911, 1995 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-7737192

RESUMO

The mammalian paired box (Pax) genes encode a family of transcription factors involved in embryogenesis. The murine and human Pax8 genes are expressed in developing and adult thyroid as well as in the developing secretory system and at the lower level in adult kidney. In the secretory system expression is localized to the induced, extensively differentiating parts that undergo a transition from mesenchyme to epithelium. The human PAX8 gene generates at least five different alternatively spliced transcripts encoding different PAX8 isoforms. These isoforms differ in their carboxy-terminal regions downstream of the paired domain that has been shown previously to be responsible for the DNA binding. The PAX8a isoform contains a 63 amino-acid serine-rich region that is absent in the isoform PAX8b whereas PAX8c reveals a novel 99-amino-acid proline-rich region. This proline-rich region arises due to an unusual reading-frame shift in the PAX8 transcript. RNAse protection and RT(reverse transcription)-PCR analysis show the expression of all three PAX8 transcripts in human thyroid, kidney and five Wilms' tumors. Band-shift assay indicates a greatly reduced binding affinity of the isoform PAX8c to a DNA sequence from the promoter of the thyroperoxidase gene compared to the binding of PAX8a and PAX8b to this sequence. Deletion analysis of murine PAX8a indicates that its activating domain residues at the carboxy terminus of the protein which is shared by isoforms PAX8a and PAX8b. In accordance with these data PAX8a and PAX8b activate transcription from a thyroglobulin promoter as well as from a cotransfected synthetic PAX8-specific promoter/chlorampericol acetyltransferase (CAT) reporter containing a Pax8-binding oligonucleotide in front of the basal herpes simplex virus thymidine kinase (HSV-TK) promoter (P11/12-TK-CAT). However if the basal HSV-TK promoter of this reporter is substituted by a minimal adenovirus E1b TATA element, PAX8a and PAX8b fail to activate transcription. Of the three chimaeric forms containing the GAL4 DNA-binding domain at the amino-terminal end fused to the corresponding carboxy-terminal regions of the PAX8 isoforms beginning immediately downstream of the paired domain only a GAL4-PAX8b fusion significantly activates transcription from a cotransfected GAL4-specific upstream-activating-sequence (UAS)-TK-CAT reporter. Substitution of the basal HSV-TK promoter in this reporter by the minimal E1b TATA element does not affect this activation. These results indicate that the PAX8 isoforms display different functional properties and may also function differently in vivo.(ABSTRACT TRUNCATED AT 400 WORDS)


Assuntos
Processamento Alternativo , Proteínas de Ligação a DNA/genética , Neoplasias Renais/genética , Proteínas Nucleares , Neoplasias da Glândula Tireoide/genética , Transativadores/genética , Tumor de Wilms/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Proteínas de Ligação a DNA/metabolismo , Humanos , Camundongos , Dados de Sequência Molecular , Fator de Transcrição PAX8 , Fatores de Transcrição Box Pareados , RNA Mensageiro/genética , Ativação Transcricional
3.
Int J Oncol ; 5(5): 1099-104, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21559686

RESUMO

We investigated binding proteins in the upstream regulatory region of c-myc gene in human liver and colon cancers. Gel shift assay revealed a nuclear protein which bound to the HindIII/PstI fragment (nt.-2328 to nt.-2118) upstream of the pi promoter of c-myc gene. DNase I footprinting showed a unique 25bp binding sequence (nt.-2305 to nt.-2281), not related to any reported elements. The amount of binding protein was higher in the cancerous than in the non-cancerous tissues. This suggests that the 25bp sequence possibly functions as a cis-acting positive element of the c-myc gene expression.

4.
J Virol ; 67(5): 2559-65, 1993 May.
Artigo em Inglês | MEDLINE | ID: mdl-8474161

RESUMO

Recent studies have demonstrated the transacting function of the X gene product of hepatitis B virus. However, little information is available on the regulation of X gene expression. In this report, we first investigate a cellular factor regulating X gene transcription by DNA transfection, using the human hepatoma cell line HuH-7, which is permissive for HBV replication as well as X mRNA transcription. A sequence-specific cellular factor was found to bind to the promoter region upstream of the first ATG (nucleotide [nt] 1248) of the X open reading frame. DNase I footprinting analysis showed the binding sequence of this factor to be situated between nt 1097 and 1119, where an 8-bp palindrome structure resides. S1 nuclease analysis of X gene transcripts demonstrated the binding site to be adjacent to two major start sites (nt 1117 and 1125) of X mRNA. Second, we demonstrate that introduction of a mutation into the binding site gives rise to a loss of the binding with a concomitant shift of the transcription start site of X mRNA beyond the 8-bp palindrome structure, causing it to become more heterogeneous. Thus, the promoter-binding protein appears to be involved in directing the transcription initiation site of the X gene toward the downstream region of the X promoter when X protein is produced from X mRNA.


Assuntos
Regulação Viral da Expressão Gênica , Genes Virais/genética , Vírus da Hepatite B/genética , Transativadores/genética , Transcrição Gênica , Sequência de Bases , Cloranfenicol O-Acetiltransferase/biossíntese , Cloranfenicol O-Acetiltransferase/genética , Mapeamento Cromossômico , Vírus da Hepatite B/crescimento & desenvolvimento , Humanos , Dados de Sequência Molecular , Mutagênese Insercional , Regiões Promotoras Genéticas , RNA Mensageiro/genética , Proteínas Recombinantes/biossíntese , Transativadores/biossíntese , Transfecção , Células Tumorais Cultivadas , Proteínas Virais Reguladoras e Acessórias , Replicação Viral
5.
Genes Dev ; 7(4): 683-93, 1993 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8096199

RESUMO

During pituitary development, the homeo domain protein GHF-1 is required for generation of somatotropes and lactotropes and for growth hormone (GH) and prolactin (PRL) gene expression. GHF-1 mRNA is detectable several days before the emergence of GH- or PRL-expressing cells, suggesting the existence of a somatotropic progenitor cell in which GHF-1 transcription is first activated. We have immortalized this cell type by using the GHF-1 regulatory region to target SV40 T-antigen (Tag) tumorigenesis in transgenic mice. The GHF-Tag transgene caused developmental entrapment of somatotropic progenitor cells that express GHF-1 but not GH or PRL, resulting in dwarfism. Immortalized cell lines derived from a transgenic pituitary tumor maintain the characteristics of the somato/lactotropic progenitor in that they express GHF-1 mRNA and protein yet fail to activate GH or PRL transcription. Using these cells, we identified an enhancer that activates GHF-1 transcription at this early stage of development yet is inactive in cells representing later developmental stages of the somatotropic lineage or in other cell types. These experiments not only demonstrate the potential for immortalization of developmental progenitor cells using the regulatory regions from cell type-specific transcription factor genes but illustrate the power of such model systems in the study of developmental control.


Assuntos
Proteínas de Ligação a DNA/genética , Nanismo Hipofisário/genética , Elementos Facilitadores Genéticos , Hormônio do Crescimento/genética , Adeno-Hipófise/embriologia , Fatores de Transcrição/genética , Animais , Diferenciação Celular/genética , Linhagem Celular Transformada , Proteínas de Ligação a DNA/fisiologia , Feminino , Regulação da Expressão Gênica , Genes Homeobox , Masculino , Camundongos , Camundongos Transgênicos , Mutagênese Sítio-Dirigida , Neoplasias Hipofisárias/genética , Células-Tronco , Fator de Transcrição Pit-1 , Fatores de Transcrição/fisiologia
6.
Jpn J Cancer Res ; 80(7): 617-21, 1989 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2507484

RESUMO

To examine the transforming potential of the X gene product of hepatitis B virus (HBV), the X-gene-containing region (referred to as the HBx region) was introduced into mouse NIH3T3 cells. Each transformed cell line expressed X-coding mRNA at a different level. A positive correlation was found between the level of X-coding mRNA and the saturation density of the cells. The HBx-transformed cell lines exhibited X protein production and tumor formation in nude mice. The function of HBV in oncogenesis may involve the continuous expression of the X-gene-coded product in the HBV DNA-integrated cells.


Assuntos
Transformação Celular Viral , Genes Virais , Vírus da Hepatite B/genética , Neoplasias Experimentais/microbiologia , Proteínas Estruturais Virais/genética , Animais , Western Blotting , Linhagem Celular , Clonagem Molecular , Camundongos , Camundongos Nus , Plasmídeos
7.
J Virol ; 63(7): 2914-20, 1989 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2542603

RESUMO

The promoter region for transcription of the 3.6-kilobase mRNA of hepatitis B virus was identified by the chloramphenicol acetyltransferase assay by using HuH-7 hepatoma cells and was found to function directly in virus production by way of the transient expression system of HBV. The 5'-upstream sequence from nucleotides 1573 to 1657 (the transcription start site) was indispensable for promoter function, while the AT-rich sequence (from nucleotides 1581 to 1604) containing a directly repeated sequence TGTT connecting the same flanking sequence PyAAAGAC (where Py is a pyrimidine) at both sides was an essential element within this promoter region. A specific cellular factor which interacted with the essential element was detected in the HuH-7 cell extract. A similar binding factor was also observed in HepG2 and huH2-2 hepatoma cells. This factor may thus be responsible for regulating 3.6-kilobase mRNA, pregenome RNA transcription, or both.


Assuntos
Proteínas de Transporte/metabolismo , Genes Virais , Vírus da Hepatite B/genética , Regiões Promotoras Genéticas , RNA Mensageiro/genética , RNA Viral/genética , Sequência de Bases , Carcinoma Hepatocelular , Linhagem Celular , Deleção Cromossômica , Elementos de DNA Transponíveis , DNA Viral/genética , Humanos , Neoplasias Hepáticas , Dados de Sequência Molecular , Peso Molecular , Mutação , Proteínas de Ligação a RNA , Transcrição Gênica
8.
Mol Biol Med ; 6(2): 151-60, 1989 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2615644

RESUMO

The function of the X gene was clarified by examination of the transient production of hepatitis B virus (HBV) particles by transfected recombinant HBV DNA (pHBV-3 DNA) and its frameshift mutant (delta X) of the X open reading frame into hepatocellular carcinoma HuH-7 and HepG2 cells. No reduction of viral mRNAs was observed in the HuH-7 cells by the delta X mutant, whereas mRNAs underwent marked reduction in HepG2 cells. No reduction in core particle production was observed in HuH-7 cells, but in HepG2 cells reduction was considerable. To clarify the significance of the delta X mutation in the trans-acting function of the X gene in hepatoma cells, the chloramphenicol acetyl/transferase (CAT) assay was conducted. Transfection of plasmid pHBV-3 into HepG2 cells increased CAT activity of pSV2-CAT, while the delta X mutation clearly showed no stimulation of activity. On the other hand, in the HuH-7 cells, pHBV-3 exhibited no such stimulation. The trans-acting function of the X gene product in two different hepatoma cells was clearly shown to differ. Furthermore, transfection of X gene expression plasmid pKSV-HBx into mouse NIH3T3 cells increased the CAT activity of pSV2-CAT. Trans-activation was still detectable even following deletion of enhancer sequences in the pSV2CAT. The oncogenic potential of HBV is discussed with special attention to the X gene product, which may be able to activate a cellular transcription factor at the viral and cellular promotor sequences in the cells.


Assuntos
Vírus da Hepatite B/genética , Oncogenes , Animais , DNA Viral/genética , Camundongos , Mutação , Plasmídeos , Transativadores , Transcrição Gênica , Transfecção , Células Tumorais Cultivadas , Replicação Viral
10.
Nihon Igaku Hoshasen Gakkai Zasshi ; 49(3): 314-26, 1989 Mar 25.
Artigo em Japonês | MEDLINE | ID: mdl-2755797

RESUMO

The basic study of intracavitary and interstitial hyperthermia was made with the Soft-Heating Method. In this method, a hybrid device composed of non-magnetic metal ring and ferrite rod is used as a heater. Being exposed to external magnetic field, the device produces heat, and its temperature rises to the Curie Temperature of the ferrite rod with self-regulation. The accuracy of the regulation is +/- 0.2 degrees C near the Curie Temperature which can be set up almost freely. In addition to that, the frequency of magnetic field is not so high (20-50 KHz) that there is no damping nor reflection of the field in a human body. Therefore the system seems to be very useful for hyperthermia of deep seated tumor. In this paper, experimental discussion of the possibility of local hyperthermia by the system is made. From the results, it is concluded that the system will be applied to clinical uses.


Assuntos
Compostos Férricos , Hipertermia Induzida/métodos , Temperatura , Animais , Cães , Hipertermia Induzida/instrumentação , Magnetismo , Modelos Estruturais
11.
J Antibiot (Tokyo) ; 41(10): 1338-50, 1988 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-3142841

RESUMO

The structures of new antitumor antibiotics, glidobactins A (Ia), B (Ib) and C (Ic) were elucidated by a combination of chemical and enzymatic degradations and spectral analyses. They have in common a cyclized tripeptide nucleus composed of L-threonine, 4(S)-amino-2(E)-pentenoic acid and erythro-4-hydroxy-L-lysine, and differ from each other in the unsaturated fatty acid moiety attached to the peptide.


Assuntos
Antibióticos Antineoplásicos , Aminoácidos , Fenômenos Químicos , Química , Ácidos Graxos , Hidrólise , Lisina/análogos & derivados , Espectroscopia de Ressonância Magnética , Peptídeos Cíclicos
12.
J Virol ; 62(9): 3513-6, 1988 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-2841501

RESUMO

Transfection of the human hepatocellular carcinoma cell line HuH7 with a plasmid containing a tandem copy of the duck hepatitis B virus DNA sequence resulted in transient replication of the virus. Viral particles secreted by transfected HuH7 cells exhibited physical properties similar to those of serum-derived duck hepatitis B virus and were infectious in primary duck hepatocyte cultures.


Assuntos
DNA Viral/biossíntese , Vírus da Hepatite B/genética , Vírion/fisiologia , Animais , Carcinoma Hepatocelular , Células Cultivadas , Imunofluorescência , Vírus da Hepatite B/fisiologia , Humanos , Fígado/microbiologia , Neoplasias Hepáticas , Hibridização de Ácido Nucleico , Transfecção , Células Tumorais Cultivadas , Replicação Viral
13.
J Virol ; 62(3): 861-5, 1988 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2828681

RESUMO

The structure of integrated viral DNA in a hepatocellular carcinoma of a duck from Chi-tung county in China was analyzed. Three different clones of integrated viral DNA, lambda DHS 6-1, lambda DHS 6-2, and lambda DHE 6-2, were obtained from the neoplastic portion of the liver by molecular cloning. One of the three clones, lambda DHS 6-1, showed inverted repetition of integrated viral DNA with chromosomal flanking sequences. Another clone, lambda DHS 6-2, showed a head-to-head configuration of the core and surface gene regions of duck hepatitis B virus (DHBV) DNA. The virus-chromosome junctions were often located near direct repeat 1 or 2 of DHBV DNA in three independent clones. Nucleotide sequences at the virus-virus junctions in two clones, lambda DHS 6-1 and 6-2, indicated the possible rearrangement of chromosomal DNA and recombination of viral DNA. DHBV DNA appears to be integrated into the genome of hepatocytes in a manner similar to that of human and woodchuck hepatitis viruses. Thus, the duck system may serve as a useful animal model for the study of human hepatocarcinogenesis.


Assuntos
Carcinoma Hepatocelular/veterinária , DNA de Neoplasias/isolamento & purificação , DNA Viral/isolamento & purificação , Vírus da Hepatite B/análise , Neoplasias Hepáticas/veterinária , Doenças das Aves Domésticas/microbiologia , Animais , Sequência de Bases , Carcinoma Hepatocelular/análise , Carcinoma Hepatocelular/microbiologia , DNA Recombinante , Patos/microbiologia , Neoplasias Hepáticas/análise , Neoplasias Hepáticas/microbiologia , Dados de Sequência Molecular
14.
Jpn J Cancer Res ; 78(12): 1341-6, 1987 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2828295

RESUMO

The human hepatoma cell line, huGK-14, containing integrated hepatitis B virus (HBV) DNAs, produced a large number of 23 nm spherical particles of HBV surface antigen (HBsAg) in a serum-free medium. These particles closely resembled the HBsAg particles found in the sera of HBV carriers and elicited a high antibody response in guinea pigs. The huGK-14 cells in a serum-free medium would provide a new, economic source of HBV vaccine.


Assuntos
Carcinoma Hepatocelular/imunologia , Antígenos de Superfície da Hepatite B/biossíntese , Neoplasias Hepáticas/imunologia , Formação de Anticorpos , Linhagem Celular , Cromatografia de Afinidade , Meios de Cultura , Eletroforese em Gel de Poliacrilamida , Humanos
16.
Hepatology ; 7(4): 753-7, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-3038724

RESUMO

The states of hepatitis B virus DNA, RNA transcripts and antigens (HBsAg and HBcAg) were studied in the liver with hepatocellular carcinoma by blot hybridization and immunohistological methods. We used whole hepatitis B virus DNA and gene specific probes (S, C and X genes) for hybridization. Integrated viral DNA was found in all five tumors, but episomal DNA was not detected in the neoplastic tissue. In the nonneoplastic cirrhotic liver, episomal DNA was found in four cases and integrated viral DNA in four cases. A large amount of hepatitis B virus-specific RNA transcripts was demonstrated in nonneoplastic liver of all five cases. Two major transcripts, 2.4 and 3.4 kb in length, were identified. The former hybridized with the S gene probe and the latter with the C gene probe, suggesting that they were messenger RNAs for HBsAg and HBcAg, respectively. In contrast to nonneoplastic liver, RNA transcripts were found in the neoplastic portion in only two cases, small in quantity; they primarily hybridized with S and X, but not with C genes. Novel species of 4.0 and 3.9 kb transcripts were found in the neoplastic and the nonneoplastic portions, respectively, in one case. They may represent fusion transcripts of integrated viral DNA and cellular flanking sequences.


Assuntos
Carcinoma Hepatocelular/análise , DNA Viral/genética , Vírus da Hepatite B/genética , Neoplasias Hepáticas/análise , RNA Viral/genética , Adulto , DNA Viral/análise , Feminino , Antígenos do Núcleo do Vírus da Hepatite B/análise , Antígenos de Superfície da Hepatite B/análise , Humanos , Masculino , Pessoa de Meia-Idade , Hibridização de Ácido Nucleico , RNA Viral/análise , Transcrição Gênica
17.
J Virol ; 61(6): 1808-13, 1987 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3033312

RESUMO

Attention was directed to hepatitis B virus (HBV) integration in tissues obtained from an hepatocellular carcinoma (HCC) of an 11-year-old boy and from the liver of his 6-year-old brother, who had chronic active hepatitis. Multiple HBV DNA integration sites were demonstrated in both tissues. Cell population(s) in the HCC and liver from the patient with chronic active hepatitis were assumed to be heterogeneous with regard to HBV integration. The integrated forms in the two tissues showed similar genetic organization without gross rearrangement. The location of one of the virus-chromosomal junctions was restricted to the 5'-end region of the minus-strand DNA of HBV. The experimental results support our previous model for the mechanism of HBV integration, in which minus-strand replicative intermediates integrate into chromosomal DNA. The integrated HBV DNAs were conserved in the same region of the viral genome, spanning from the C gene through the S gene to the X gene, which contains intrinsic promoter-enhancer sequences.


Assuntos
Carcinoma Hepatocelular/análise , DNA de Neoplasias/análise , DNA Viral/isolamento & purificação , Vírus da Hepatite B/isolamento & purificação , Neoplasias Hepáticas/análise , Sequência de Bases , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/microbiologia , Criança , Genes Virais , Hepatite B/genética , Vírus da Hepatite B/genética , Hepatite Crônica/genética , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/microbiologia , Masculino
18.
Proc Natl Acad Sci U S A ; 84(9): 2678-82, 1987 May.
Artigo em Inglês | MEDLINE | ID: mdl-3033659

RESUMO

An in vitro system for the production of hepatitis B virus (HBV) particles was established by the transient expression of transfected HBV DNA using a human hepatocellular carcinoma cell, HuH-7, as a recipient. The 3.6- and 2.2-kilobase transcripts observed were similar to those in virus-infected liver cells. Both transcripts revealed the microheterogeneity of their 5' ends. The formation of virus-related particles subsequent to the RNA transcription was demonstrated. The core particles observed in the cytoplasm and the virus particles secreted in the culture medium contained the replicative intermediates of HBV DNA and banded at densities of 1.35-1.36 g/cm3 and 1.22-1.24 g/cm3, respectively. Furthermore, the in vitro mutagenesis of the template HBV DNA demonstrated that the P gene as well as the C gene products were essential for the production of HBV particles.


Assuntos
DNA Viral/genética , Vírus da Hepatite B/genética , Transfecção , Sequência de Aminoácidos , Sequência de Bases , Carcinoma Hepatocelular , Linhagem Celular , Enzimas de Restrição do DNA , Humanos , Neoplasias Hepáticas , Moldes Genéticos , Transcrição Gênica
19.
Nihon Naibunpi Gakkai Zasshi ; 62(7): 755-75, 1986 Jul 20.
Artigo em Japonês | MEDLINE | ID: mdl-3023151

RESUMO

This study was designed to clarify the cause of hyporeninemic hypoaldosteronism (HH) associated with diabetes mellitus. Fourty diabetic patients (DP) were divided into 3 groups; 12 patients without neuropathy or nephropathy, 13 with neuropathy and without nephropathy, and 15 with neuropathy and nephropathy; in the third group 3 HH patients were included. Fourteen normal subjects served as controls. In all DP and the normal subjects, plasma concentration of aldosterone (PAld), 18-hydroxycorticosterone (P18-OH-B), corticosterone (PB), 11-deoxycorticosterone (PDOC) and cortisol (PF) were measured before and after intravenous administration of angiotensin II (AII, 10 ng/kg/min, for 30 min) or ACTH (1-24 ACTH, 0.25 mg). In 27 DP, plasma renin activity (PRA) increased from 0.8 +/- 0.6 SD to 2.4 +/- 2.2 ng/ml/h (normal: 1.2 +/- 0.7 to 3.2 +/- 1.7 ng/ml/h) 2 hours after intravenous administration of furosemide (1 mg/kg) and assumption of the upright posture. No significant difference in PRA was found between DP and controls, whereas the response to these stimuli decreased significantly in 9 DP with neuropathy and nephropathy (from 0.4 +/- 0.2 to 0.7 +/- 0.4 ng/ml/h). The major results were as follows: 1) The mean of PAld (5.9 +/- 2.4 ng/100 ml) in DP was significantly lower than that in controls (7.7 +/- 2.2 ng/100 ml). There was no significant difference of PAld between DP without complications and controls. PAld in DP with neuropathy alone (5.0 +/- 1.5 ng/100 ml, p less than 0.05) and that in DP with neuropathy and nephropathy (4.7 +/- 2.4 ng/100 ml, p less than 0.05) were lower than that in controls. The mean of P18-OH-B (12.3 +/- 4.3 ng/100 ml) in DP was similar to that (14.2 +/- 3.2 ng/100 ml) in controls. P18-OH-B in DP without complications and that in DP with neuropathy alone were similar to that in controls. However, P18-OH-B (8.8 +/- 3.2 ng/100 ml) in DP with neuropathy and nephropathy was significantly lower than that in controls (p less than 0.001). No difference in PB, PDOC or PF was observed between DP and controls. 2) PAld increased from 6.0 +/- 2.5 ng/100 ml in DP (p less than 0.001) and from 7.6 +/- 2.2 to 15.7 +/- 5.3 ng/100 ml in controls (p less than 0.001) 30 min after A II infusion.(ABSTRACT TRUNCATED AT 400 WORDS)


Assuntos
Hormônio Adrenocorticotrópico/farmacologia , Aldosterona/sangue , Angiotensina II/farmacologia , Corticosterona/sangue , Diabetes Mellitus Tipo 2/sangue , Hidrocortisona/sangue , 18-Hidroxicorticosterona/sangue , Adulto , Idoso , Desoxicorticosterona/sangue , Nefropatias Diabéticas/sangue , Neuropatias Diabéticas/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sistema Renina-Angiotensina/efeitos dos fármacos
20.
Nihon Naibunpi Gakkai Zasshi ; 62(3): 197-207, 1986 Mar 20.
Artigo em Japonês | MEDLINE | ID: mdl-3709883

RESUMO

There is considerable information suggesting that dopamine is a physiological regulator of aldosterone secretion. Metoclopramide, a specific dopamine antagonist, elicits a rapid rise in plasma aldosterone independent of the known aldosterone-regulating factors. However, the mechanism and the site of action of metoclopramide, whether adrenal or extra-adrenal, in stimulation of aldosterone production remain to be defined. The present studies were designed to investigate the mechanism of dopaminergic control of corticosteroid secretion and to determine at which step in the aldosterone biosynthetic pathway metoclopramide and dopamine exert their effect. Plasma concentrations of progesterone, 11-deoxycorticosterone (DOC), and cortisol were not altered by a bolus intravenous administration of 10 mg metoclopramide in 8 healthy male volunteers. Metoclopramide increased plasma aldosterone from 6.9 +/- 2.8 (Mean +/- 2SD) ng/100 ml to a maximum level of 18.2 +/- 4.7 ng/100 ml, 18-hydroxycorticosterone (18-OHB) from 12.6 +/- 6.5 ng/100 ml to a maximum of 41.3 +/- 7.3 ng/100 ml and corticosterone from 0.36 +/- 0.09 microgram/100 ml to a maximum of 0.85 +/- 0.22 microgram/100 ml. The aldosterone, 18-OHB and corticosterone responses displayed a parallel time course, with a significant response of each occurring within 5 minutes after metoclopramide administration. These data suggest that metoclopramide may modulate the activities of 18-hydroxylase and 11 beta-hydroxylase. Studies in vitro revealed that metoclopramide (10(-8)-10(-4) M had little effect on basal production of aldosterone, 18-OHB and corticosterone from human adrenal slices. Dopamine (10(-4) M) did not alter the basal secretion of aldosterone, 18-OHB and corticosterone, but suppressed the secretion of these 3 mineralocorticoids by ACTH, which were diminished by addition of 10(-4) M metoclopramide. There was a concentration-dependent inhibitory effect of dopamine on conversion of corticosterone to 18-OHB and DOC to corticosterone in vitro using bovine adrenal mitochondrial fractions. IC50 of dopamine inhibiting 18-hydroxylation and 11 beta-hydroxylation were 7.5 X 10(-7) M and 9.5 X 10(-4) M, respectively. It appears that physiological concentration of dopamine can modulate the activity of 18-hydroxylase enzyme. In summary, it can be concluded that the in vivo and in vitro studies are compatible with a view that dopamine has a physiological role in the regulation of aldosterone by modulating the activity of 18-hydroxylase enzyme.


Assuntos
Dopamina/farmacologia , Metoclopramida/farmacologia , Mineralocorticoides/metabolismo , 18-Hidroxicorticosterona/metabolismo , Córtex Suprarrenal/metabolismo , Adulto , Aldosterona/metabolismo , Corticosterona/metabolismo , Desoxicorticosterona/metabolismo , Humanos , Técnicas In Vitro , Masculino , Progesterona/metabolismo
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