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1.
Mol Biol (Mosk) ; 55(5): 870-880, 2021.
Artigo em Russo | MEDLINE | ID: mdl-34671007

RESUMO

Annexin A8 (ANXA8) is a member of the annexin family, which had been reported to regulate multiple cancer cellular processes including proliferation, metastasis and inflammation. However, the specific role of ANXA8 in lung cancer cell biology remains unknown. Our previous transcriptome study revealed that ANXA8 mRNA was downregulated in curcumin analog (MHMD) -treated human non-small lung cancer cells (A549 cell line). Here, we continued to study the ANXA8 expression in A549 cells using reverse transcription-quantitative PCR and Western blotting, compared with that in human normal bronchial epithelium cells (BE-AS-2B cell line). Overexpression of ANXA8 via transfection of pEGFP-ANXA8 recombinant vector contributed to the proliferation and migration of A549 cells. Moreover, the cell cycle protein cyclin E1 was upregulated in ANXA8-transfected A549 cells. Knockdown of ANXA8 using an RNA interference technique decreased A549 cell viability and restrained their migration in vitro. The expression levels of multiple cellular factors, including EGFR, PI3K, Akt, mTOR, p70S6K and 4EBP1, in the epidermal growth factor receptor (EGFR) signaling pathway were also altered by ANXA8 knockdown or overexpression in A549 cells, which confirmed the activation of the EGFR/Akt/mTOR signaling pathway by ANXA8. The present results provided evidence to support further investigation of the functional identification of ANXA8 in lung cancer cells in the future.


Assuntos
Anexinas/fisiologia , Neoplasias Pulmonares , Proteínas Proto-Oncogênicas c-akt , Células A549 , Anexinas/genética , Anexinas/metabolismo , Proliferação de Células/genética , Receptores ErbB/genética , Humanos , Neoplasias Pulmonares/genética , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo
3.
Zhonghua Yi Xue Za Zhi ; 99(5): 380-383, 2019 Jan 29.
Artigo em Chinês | MEDLINE | ID: mdl-30772981

RESUMO

Objective: To investigate the related risk factors for hemorrhagic transformation (HT) of cerebellar infarction after posterior fossa decompression surgery. Methods: A total of 91 patients with cerebellar infarction were treated by posterior fossa decompression surgery in Department of Neurosurgery of Jinhua Municipal Central Hospital from Jan 2010 to Jan 2018, were selected as study subjects. The HT group included 17 cases, while the Non-HT group included 74 cases. The clinical data of the two groups were analyzed retrospectively, the univariate and non-conditional lgistic regression analysis were performed to detect the relevant risk factors for hemorrhagic transformation of cerebellar infarction after posterior fossa decompression surgery. Results: By univariate analysis, the differences of these seven risk factors, the large area cerebellar infarction (the diameter of area was larger than 5 cm), pre-op thrombolysis, pre-op mild HT, oral anticoagulants, atrial fibrillation, hyperglycemia and fluctuation of BP in post-op, between two groups were statistically significant (P<0.05). By multivariate logistic analysis, the large area cerebellar infarction (P<0.05), pre-op thrombolysis(P<0.01), pre-op mild HT (P<0.01), oral anticoagulants (P<0.01) were the independent risk factors for post-op HT. Conclusions: The large area cerebellar infarction (the diameter of area was more than 5 cm), pre-op thrombolysis, pre-op mild HT, oral anticoagulants, atrial fibrillation, hyperglycemia and fluctuation of BP in post-op are important risk factors for post-op HT. The large area cerebellar infarction, pre-op thrombolysis, pre-op mild HT, oral anticoagulants are the independent risk factors for post-op HT. A proper pre-op evaluation of these risk factors and an individualized treatment for post-op HT would help a lot with balancing operational risk and improving prognosis.


Assuntos
Isquemia Encefálica , Acidente Vascular Cerebral , Humanos , Infarto , Estudos Retrospectivos , Fatores de Risco
4.
Eur Rev Med Pharmacol Sci ; 23(2): 670-678, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30720199

RESUMO

OBJECTIVE: Long non-coding RNA HOX transcript antisense RNA (HOTAIR) is reported to make chromatin state, cell growth and cancer metastasis. However, the role of HOTAIR in non-small cell lung cancer (NSCLC) remains unknown. The aim of this study was to explore the regulatory mechanism of HOTAIR in NSCLC in relation to miR-217/Dachshund homolog 1 (DACH1) signaling pathway. MATERIALS AND METHODS: The expression levels of HOTAIR and miR-217 were measured by quantitative Polymerase Chain Reaction (qPCR) in NSCLC cell lines and human bronchial epithelial cell line HBE. The direct target of HOTAIR and miR-217 in NSCLC was confirmed by a Luciferase reporter assay. The expression of DACH1 protein was examined by Western blot (WB) assay. Cell migration and invasion were examined with transwell assays, and cell proliferation was measured by Cell Counting Kit-8 (CCK8) assay. RESULTS: HOTAIR was up-regulated and miR-217 was down-regulated in NSCLC cell lines. Silencing of HOTAIR significantly repressed cell proliferation and inhibited cell migration and invasion in H1299 and A549 cells by facilitating miR-217 expression. Moreover, bioinformatics analysis and Luciferase reporter assay confirmed that DACH1 was a target of miR-217. Furthermore, the overexpression of miR-217 markedly repressed cell proliferation and inhibited cell migration and invasion in H1299 and A549 cells. DACH1 reverses the effects of miR-217 overexpression in NSCLC cells. CONCLUSIONS: HOTAIR was up-regulated in NSCLC cell and regulates the proliferation, migration, invasion through the miR-217/DACH1 signaling pathway. It provides a novel potential treatment strategy for NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Proteínas do Olho/genética , Neoplasias Pulmonares/genética , MicroRNAs/genética , RNA Longo não Codificante/metabolismo , Fatores de Transcrição/genética , Células A549 , Carcinoma Pulmonar de Células não Pequenas/patologia , Movimento Celular/genética , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/patologia , MicroRNAs/metabolismo , Invasividade Neoplásica/genética , Regulação para Cima
5.
Genet Mol Res ; 15(3)2016 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-27706772

RESUMO

The WRKY family is one of the most important transcription factor families in plants, involved in the regulation of a broad range of biological roles. The recent releases of whole-genome sequences of pepper (Capsicum annuum L.) allow us to perform a genome-wide identification and characterization of the WRKY family. In this study, 61 CaWRKY proteins were identified in the pepper genome. Based on protein structural and phylogenetic analyses, these proteins were classified into four main groups (I, II, III, and NG), and Group II was further divided into five subgroups (IIa to IIe). Chromosome mapping analysis indicated that CaWRKY genes are distributed across all 12 chromosomes, although the location of four CaWRKYs (CaWRKY58-CaWRKY61) could not be identified. Two pairs of CaWRKYs located on chromosome 01 appear to be tandem duplications. Furthermore, the phylogenetic tree showed a close evolutionary relationship of WRKYs in three species from Solanaceae. In conclusion, this comprehensive analysis of CaWRKYs will provide rich resources for further functional studies in pepper.


Assuntos
Capsicum/genética , Simulação por Computador , Genes de Plantas , Família Multigênica , Proteínas de Plantas/genética , Fatores de Transcrição/genética , Sequência de Aminoácidos , Cromossomos de Plantas/genética , Sequência Conservada/genética , Éxons/genética , Duplicação Gênica/genética , Íntrons/genética , Solanum lycopersicum/genética , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Alinhamento de Sequência , Solanum tuberosum/genética , Fatores de Transcrição/química , Fatores de Transcrição/metabolismo
7.
Br J Dermatol ; 174(1): 176-9, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26440558

RESUMO

Corynespora cassiicola is a plant pathogen associated with leaf-spotting disease. The fungus has been found on diverse substrates: leaves, stems and roots of plants; nematode cysts and human skin. It rarely causes human infections. Here we report one case of subcutaneous phaeohyphomycosis caused by C. cassiicola with prominent tissue necrosis in a woman. All of her clinical features pointed towards a genetic linkage. Hence, whole-exome sequencing and Sanger sequencing were performed on this patient. One mutation of CARD9 was detected.


Assuntos
Ascomicetos , Proteínas Adaptadoras de Sinalização CARD/genética , Dermatomicoses/genética , Dermatoses Faciais/genética , Mutação/genética , Adulto , Proteínas Adaptadoras de Sinalização CARD/deficiência , Feminino , Humanos
8.
Genet Mol Res ; 14(3): 7947-56, 2015 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-26214476

RESUMO

Tomato yellow leaf curl virus is one of the main diseases affecting tomato production worldwide. Previous studies have shown that Ty-2 is an important resistance gene located between molecular markers C2_At2g28250 (82.3 cM) and T0302 (89.0 cM), and exhibits strong resistance to tomato yellow leaf curl virus in Asia. In this study, Ty-2 candidate genes were subjected to bioinformatic analysis for the sequenced tomato genome. We identified 69 genes between molecular markers C2_At2g28250 and T0302, 22 of which were disease-related resistant genes, including nucleotide binding site-leucine-rich repeat disease resistance genes, protease genes (protein kinase, kinase receptor, and protein isomerase), cytochromes, and transcription factors. Expressed sequence tag analysis revealed that 77.3% (17/22) of candidate disease-resistance genes were expressed, involving 143 expressed sequence tags. Based on full-length cDNA sequence analysis, 7 candidate genes were found, 4 of which were involved in tomato responses to pathogens. Microarray expression analysis also showed that most candidate genes were involved in the tomato responses to multiple pathogens, including fungi, viruses, and bacteria. RNA-seq expression analysis revealed that all candidate genes participated in tomato growth and development.


Assuntos
Mapeamento Cromossômico , Simulação por Computador , Resistência à Doença/genética , Genes de Plantas , Doenças das Plantas/genética , Solanum lycopersicum/genética , Solanum lycopersicum/virologia , Begomovirus/fisiologia , DNA Complementar/genética , Etiquetas de Sequências Expressas , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Estudos de Associação Genética , Análise de Sequência com Séries de Oligonucleotídeos , Doenças das Plantas/virologia , Análise de Sequência de RNA
9.
Genet Mol Res ; 14(1): 21-8, 2015 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-25729931

RESUMO

We aimed to explore the changes of peripheral B1 cells before and after treatment of adult idiopathic thrombocytopenic purpura (ITP) and to investigate the association of these changes with the disease condition and prognosis. Ninety-seven ITP patients were divided into the effective or ineffective groups, based on their response to hormone therapy. Forty healthy volunteers were enrolled into the control group (HC). The percentages of CD19+ cells, B1 cells, and platelet-associated immunoglobulin (PAIg) in peripheral blood from healthy volunteers and ITP patients before and after treatment were evaluated, and blood platelet (PLT) counts were determined. The percentages of CD19+ cells [(21 ± 10.0) vs (11.2 ± 7.1)%], B1 cells [(8.85 ± 5.23) vs (2.2 ± 1.3)%], and PAIg [(28 ± 19) vs (11.7 ± 8)%] in whole blood from ITP patients before treatment were significantly higher than those in whole blood from healthy controls (P < 0.05). Before treatment, the percentage of B1 cells and PAIg in ITP patients was negatively correlated with the PLT level (r = -0.89, P < 0.05 and r = -0.814, P < 0.05, respectively). Further, the B1 cell percentage was positively associated with the PAIg percentage in ITP patients before treatment. In the effective group, the B1 cell percentage was reduced sharply at 1 month after treatment [(2.45 ± 1.75) vs (8.74 ± 5.04)%, P < 0.05)], so as at 3 and 6 months. However, in the ineffective group, there was no difference in the B1 cell percentage before and after treatment [(7.9 ± 5.6) vs (8.76 ± 5.26)%]. This obvious association of changes in peripheral B1 cells with disease condition and prognosis in ITP patients may be of certain clinical significance for guiding the individualized treatment of ITP.


Assuntos
Linfócitos B/imunologia , Medicina de Precisão , Púrpura Trombocitopênica Idiopática/imunologia , Púrpura Trombocitopênica Idiopática/terapia , Adolescente , Adulto , Idoso , Antígenos CD19/metabolismo , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas , Prognóstico , Púrpura Trombocitopênica Idiopática/sangue , Adulto Jovem
10.
Genet Mol Res ; 14(1): 529-37, 2015 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-25729988

RESUMO

The objective of the present study was to analyze the genetic diversity of tomato yellow leaf curl virus (TYLCV). Representative TYLCV sequences were searched in the National Center for Biotechnology Information database. Comprehensive analysis of TYLCV was performed using bioinformatics by examining gene structure, sequence alignments, phylogeny, GC content, and homology. Forty-eight representative TYLCV sequences were selected from 48 regions in 29 countries. The results showed that all TYLCV sequences were 2752-2794 nucleotides in length, which encoded 6 open reading frames (AV1, AV2, AC1, AC2, AC3, and AC4). GC content ranged from 0.41-0.42. Sequence alignment showed a number of insertions and deletions within these TYLCV sequences. Phylogenetic tree results revealed that the sequences were divided into 10 classes; homology of the sequences ranged from 72.8 to 98.6%. All 48 sequences contained the typical structure of TYLCV, including open reading frames and intergenic regions. These results provide a theoretical basis for the identification and evolution of the virus in the future.


Assuntos
Begomovirus/genética , Variação Genética , Solanum lycopersicum/virologia , Composição de Bases/genética , Sequência de Bases , Begomovirus/isolamento & purificação , Sequência Conservada , Filogenia , Homologia de Sequência do Ácido Nucleico
11.
Vet Pathol ; 52(6): 1258-62, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25689989

RESUMO

Siniperca chuatsi rhabdovirus (SCRV) is one of myriad rhabdoviruses recorded in fish. Preliminary data show that inhibition of the SCRV nucleoprotein (N) could significantly reduce the progeny virus titers in infected Epithelioma papulosum cyprinid (EPC) cells. Here, the authors propose that cleavage of the viral 47-kDa N protein is caspase-mediated based on caspase inhibition experiments, transient expression in EPC transfection, and analysis of cleavage sites. Cleavage of the SCRV N protein in culture was prevented by a pan-caspase inhibitor, z-VAD-FMK (z-Val-Ala-DL-Asp-fluoromethyl ketone). Subsequently, N was transiently expressed in EPC cells, the results of which indicated that the specific cleavage of N also occurred in the cells transfected with N-GFP plasmid. Several truncated fragments of the N gene were constructed and transiently transfected into EPC cells. Immunoblotting results indicated that D324 and D374 are the cleavage sites of N by caspases. The authors also found that z-VAD-FMK could inhibit the cytopathic effect in SCRV-infected EPC cells but not affect the production of infectious progeny, suggesting that the caspase-mediated cleavage of N protein is not required for in vitro SCRV replication. To the authors' knowledge, this is the first report on the cleavage of rhabdovirus proteins.


Assuntos
Clorometilcetonas de Aminoácidos/farmacologia , Inibidores de Caspase/farmacologia , Caspases/metabolismo , Doenças dos Peixes/virologia , Nucleoproteínas/metabolismo , Rhabdoviridae/metabolismo , Animais , Apoptose , Caspases/genética , Peixes , Genes Reporter , Proteólise/efeitos dos fármacos , Proteínas Virais/metabolismo , Replicação Viral/efeitos dos fármacos
12.
Eur Rev Med Pharmacol Sci ; 18(20): 3134-8, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25392116

RESUMO

OBJECTIVE: To investigate the anticancer properties of a chemosynthetic curcumin analog, (1E,6E)-4-((furan-2-yl)methylene)-1,7-bis(4-hydroxy-3-methoxyphenyl)hepta-1,6-diene-3,5-dione (C26H22O7, abbreviated MHMD) in A549 cells. MATERIALS AND METHODS: Inverted microscope was used to observe the alteration on cytomorphology. MTT assay was used to detect cell viability. Acridine-orange staining was used to measure autophagy, and AnnexinV/PI staining and Hoechst/PI staining to measure apoptosis and necrosis. RESULTS: MTT assays showed that at 12 h, 24 h, 48 h, MHMD reduced cell viability with an IC50 of 27.46 µM, 18.86 µM, and 11.23 µM, respectively. Typical characteristics were observed in concert with cell death, including treated-cells getting brighter, rounder, and becoming non-adherent gradually. Additionally, acridine-orange staining suggested that autophagy didn't involve in MHMD-induced cell death. However, apoptosis and necrosis played important roles in MHMD-induced cell death by Hoechst33342/PI staining. It showed apoptosis was the main cause at low concentrations (≤ 4 µM), while with the concentrations rising, necrosis was the leading role. AnnexinV/PI staining again indicated the occurrence of apoptosis at 4 µM. Furthermore, the caspases inhibitor z-VAD-fmk could prevent MHMD-induced cell death, which showed much higher cell viability than those only treated with MHMD (4 µM). Moreover, MTT assay also demonstrated that MHMD did possess a greater anti-proliferative ability than curcumin. CONCLUSIONS: The curcumin analog MHMD is able to induce A549 cell death in a time and dose-dependent manner via apoptosis and necrosis. And MHMD could be a more effective drug than curcumin.


Assuntos
Apoptose/efeitos dos fármacos , Curcumina/análogos & derivados , Curcumina/farmacologia , Neoplasias Pulmonares/patologia , Apoptose/fisiologia , Autofagia/efeitos dos fármacos , Autofagia/fisiologia , Morte Celular/efeitos dos fármacos , Morte Celular/fisiologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Curcumina/uso terapêutico , Relação Dose-Resposta a Droga , Humanos , Neoplasias Pulmonares/tratamento farmacológico
14.
J Med Imaging Radiat Oncol ; 54(1): 17-23, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20377710

RESUMO

This study aims to evaluate medical student and intern awareness of ionising radiation exposure from common diagnostic imaging procedures and to suggest how education could be improved. Fourth to sixth year medical students enrolled at a Western Australian university and interns from three teaching hospitals in Perth were recruited. Participants were asked to complete a questionnaire consisting of 26 questions on their background, knowledge of ionising radiation doses and learning preferences for future teaching on this subject. A total of 331 completed questionnaires were received (95.9%). Of the 17 questions assessing knowledge of ionising radiation, a mean score of 6.0 was obtained by respondents (95% CI 5.8-6.2). Up to 54.8% of respondents underestimated the radiation dose from commonly requested radiological procedures. Respondents (11.3 and 25.5%) incorrectly believed that ultrasound and MRI emit ionising radiation, respectively. Of the four subgroups of respondents, the intern doctor subgroup performed significantly better (mean score 6.9, P < 0.0001, 95% CI 6.5-7.3) than each of the three medical student subgroups. When asked for the preferred method of teaching for future radiation awareness, a combination of lectures, tutorials and workshops was preferred. This study has clearly shown that awareness of ionising radiation from diagnostic imaging is lacking among senior medical students and interns. The results highlight the need for improved education to minimise unnecessary exposure of patients and the community to radiation. Further studies are required to determine the most effective form of education.


Assuntos
Conscientização , Diagnóstico por Imagem , Conhecimentos, Atitudes e Prática em Saúde , Internato e Residência , Radiação Ionizante , Estudantes de Medicina/psicologia , Adulto , Análise de Variância , Educação de Pós-Graduação em Medicina , Educação de Graduação em Medicina , Feminino , Humanos , Masculino , Doses de Radiação , Efeitos da Radiação , Fatores de Risco , Segurança , Inquéritos e Questionários
15.
Chin Med J (Engl) ; 106(2): 93-6, 1993 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8389276

RESUMO

The in vitro anti-viral activity of garlic extract (GE) on human cytomegalovirus (HCMV) was evaluated by tissue culture, plaque reduction and early antigen assay. A dose dependent inhibitory effect of GE was evident when GE was applied simultaneously with HCMV. But the effect was stronger when the monolayers were pretreated with GE. In addition, the anti-viral effect of GE persisted long in infected cells after its being removed from the culture medium. The strongest anti-viral effect of GE was demonstrated when it was applied continuously. It is therefore recommended that clinical use of GE against HCMV infection should be persistent and the prophylactic use of GE is preferable in immunocompromised patients.


Assuntos
Antivirais/farmacologia , Citomegalovirus/efeitos dos fármacos , Alho , Plantas Medicinais , Humanos , Extratos Vegetais/farmacologia , Ensaio de Placa Viral
16.
Neuropharmacology ; 30(7): 775-86, 1991 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1656309

RESUMO

Quantitative ligand binding studies have been used to characterize binding sites for N-allylnormetazocine ((+)SKF10,047) (SKF), 1-(1-phenylcyclohexyl) piperidine (PCP), N-[1-(2-thienyl)cyclohexyl]piperidine (TCP) and haloperidol in membranes from the brain of rat and guinea pig under conditions which permitted simultaneous analysis of the binding of both PCP and SKF. Using four labelled ligands (SKF, TCP, PCP and haloperidol), each displaced by the corresponding four unlabelled ligands, four classes of binding sites were observed in membranes from the brain of the rat, corresponding to sigma (sigma), two classes of PCP sites (PCP1, PCP2) and dopamine (D2) sites. The sigma site was suppressed by 50 nM haloperidol, while the PCP1 and PCP2 sites were not. These results were confirmed by studies employing a self- and cross-displacement design and dose-response surfaces for SKF and TCP, with and without blockade by haloperidol of the sigma site. Using mathematical modelling, employing the program LIGAND, it was possible to reject simpler models involving a common "PCP/sigma" site or a model involving only two classes of sites (sigma and PCP). Similar methods were used to identify two classes of sigma binding sites and two classes of PCP binding sites, in membranes prepared from the brain of the guinea pig. The relative potencies of 18 ligands for displacement of (+)[3H]SKF10,047 and [3H]TCP were compared: there were significant qualitative and quantitative differences in the "sigma" binding sites in the brain of rat and guinea pig, while the PCP binding sites were very similar in the two species.


Assuntos
Encéfalo/metabolismo , Fenazocina/análogos & derivados , Fenciclidina/metabolismo , Receptores Opioides/metabolismo , Animais , Sítios de Ligação , Membrana Celular/metabolismo , Cobaias , Masculino , Fenazocina/metabolismo , Fenciclidina/análogos & derivados , Psicotrópicos/farmacologia , Ensaio Radioligante , Ratos , Ratos Endogâmicos , Receptores Opioides/efeitos dos fármacos , Receptores sigma
18.
Eur J Pharmacol ; 206(4): 261-9, 1991 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-1655487

RESUMO

Computer-assisted, simultaneous analysis of self- and cross-displacement experiments demonstrated the existence of several binding sites in guinea pig brain for dextromethorphan, (+)-3-(3-hydroxyphenyl)-N-(1-propyl)piperidine ((+)-3-PPP), and 1,3-di-o-tolyl guanidine (DTG). Dextromethorphan binds with high affinity to two sites (R1 Kd 50-83 and R2 Kd 8-19 nM) and with low affinity to two additional sites (R3 and R4). (+)-3-PPP binds to one high-affinity (R1 Kd 24-36 nM), to one intermediate-affinity (R3 Kd 210-320 nM), and to two (R2 and R4) low-affinity sites. DTG binds with almost identical high affinity to two different sites (R1 Kd 22-24 and R3 Kd 13-16 nM). These results confirm that dextromethorphan, (+)-3-PPP, and DTG bind to the common DM1/sigma 1 site (R1). The binding of DTG to two different sites with identical affinities precludes the use of this compound as a specific marker for sigma receptors. Besides, haloperidol displaces labeled ligands from both high-affinity DTG sites (R1 and R3) with high affinity. Thus, haloperidol sensitivity should not be used as the single criterion to identify a putative receptor. The resolution of these novel sites also may provide new insights into the multiple effects of antipsychotic drugs. In addition, this investigation has important implications regarding the methods that must be applied to characterize multiple binding sites and their relations with putative receptors.


Assuntos
Encéfalo/metabolismo , Dextrometorfano/metabolismo , Receptores Opioides/metabolismo , Animais , Sítios de Ligação , Ligação Competitiva , Encéfalo/ultraestrutura , Simulação por Computador , Guanidinas/metabolismo , Cobaias , Haloperidol/metabolismo , Cinética , Masculino , Modelos Biológicos , Piperidinas/metabolismo , Receptores sigma , Trítio
19.
J Recept Res ; 10(1-2): 11-27, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2262931

RESUMO

The present investigation attempted to differentiate haloperidol-sensitive sigma sites (sigma H) from phencyclidine (PCP) binding sites in rat brain membranes. We studied the effects of several cations at physiologically relevant concentrations on the binding of radioligands selective for sigma H sites ([3H]haloperidol, [3H](+)3-PPP**), and [3H](+)SKF10,047), or for PCP sites ([3H]PCP and [3H]TCP). The PCP sites displayed a markedly greater sensitivity to cations than sigma H sites. This property was reflected by a greater extent of inhibition of the binding of PCP-selective relative to sigma H-selective ligands at a given cation concentration, as well as by lower IC50's and by steeper slopes of the cation dose-response curves. Divalent cations were approximately 100 times more potent than monovalent cations. All cations were inhibitory, except Sr2+ and Ba2+ which, at micromolar concentrations, enhanced PCP binding but not sigma H binding. Thus, PCP-selective sites appeared to be distinct from sigma H sites with regards to several aspects of cation modulation. This is consistent with the view that PCP and sigma H sites are distinct molecular entities. Further, the marked cation sensitivity of the PCP site is consistent with the current hypothesis according to which the PCP site is linked to the N-methyl-D-aspartate (NMDA) receptor-cation channel complex.


Assuntos
Encéfalo/ultraestrutura , Cátions/farmacologia , Fenciclidina/metabolismo , Fator sigma/metabolismo , Animais , Sítios de Ligação , Encéfalo/metabolismo , Relação Dose-Resposta a Droga , Haloperidol/farmacologia , Ligantes , Masculino , Fenazocina/análogos & derivados , Fenazocina/metabolismo , Ratos , Ratos Endogâmicos , Trítio
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