Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 4 de 4
Filtrar
Mais filtros








Base de dados
Intervalo de ano de publicação
1.
Toxicol Appl Pharmacol ; 414: 115428, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33524449

RESUMO

Researches have shown that calcitonin gene-related peptide (CGRP) plays a pivotal role in pain modulation. Nociceptive information from the periphery is relayed from parabrachial nucleus (PBN) to brain regions implicated involved in pain. This study investigated the effects and mechanisms of CGRP and CGRP receptors in pain regulation in the PBN of naive and neuropathic pain rats. Chronic sciatic nerve ligation was used to model neuropathic pain, CGRP and CGRP 8-37 were injected into the PBN of the rats, and calcitonin receptor-like receptor (CLR), a main structure of CGRP receptor, was knocked down by lentivirus-coated CLR siRNA. The hot plate test (HPT) and the Randall Selitto Test (RST) was used to determine the latency of the rat hindpaw response. The expression of CLR was detected with RT-PCR and western blotting. We found that intra-PBN injecting of CGRP induced an obvious anti-nociceptive effect in naive and neuropathic pain rats in a dose-dependent manner, the CGRP-induced antinociception was significantly reduced after injection of CGRP 8-37, Moreover, the mRNA and protein levels of CLR, in PBN decreased significantly and the antinociception CGRP-induced was also significantly lower in neuropathic pain rats than that in naive rats. Knockdown CLR in PBN decreased the expression of CLR and the antinociception induced by CGRP was observably decreased. Our results demonstrate that CGRP induced antinociception in PBN of naive or neuropathic pain rats, CGRP receptor mediates this effect. Neuropathic pain induced decreases in the expression of CGRP receptor, as well as in CGRP-induced antinociception in PBN.


Assuntos
Analgésicos/farmacologia , Peptídeo Relacionado com Gene de Calcitonina/farmacologia , Proteína Semelhante a Receptor de Calcitonina/agonistas , Dor Nociceptiva/prevenção & controle , Limiar da Dor/efeitos dos fármacos , Núcleos Parabraquiais/efeitos dos fármacos , Fragmentos de Peptídeos/farmacologia , Receptores de Peptídeo Relacionado com o Gene de Calcitonina/agonistas , Ciática/prevenção & controle , Animais , Proteína Semelhante a Receptor de Calcitonina/genética , Proteína Semelhante a Receptor de Calcitonina/metabolismo , Modelos Animais de Doenças , Regulação da Expressão Gênica , Masculino , Dor Nociceptiva/genética , Dor Nociceptiva/metabolismo , Dor Nociceptiva/fisiopatologia , Núcleos Parabraquiais/metabolismo , Núcleos Parabraquiais/fisiopatologia , Ratos Sprague-Dawley , Receptores de Peptídeo Relacionado com o Gene de Calcitonina/genética , Receptores de Peptídeo Relacionado com o Gene de Calcitonina/metabolismo , Ciática/genética , Ciática/metabolismo , Ciática/fisiopatologia
2.
Biochemistry ; 56(30): 3877-3880, 2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28691801

RESUMO

The second extracellular loop (ECL2) of the G protein-coupled receptor (GPCR) family is important for ligand interaction and drug discovery. ECL2 of the family B cardioprotective calcitonin gene-related peptide (CGRP) receptor is required for cell signaling. Family B GPCR ligands have two regions; the N-terminus mediates receptor activation, and the remainder confers high-affinity binding. Comparing antagonism of CGRP8-37 at a number of point mutations of ECL2 of the CGRP receptor, we show that the ECL2 potentially facilitates interaction with up to the 18 N-terminal residues of CGRP. This has implications for understanding family B GPCR activation and for drug design at the CGRP receptor.


Assuntos
Peptídeo Relacionado com Gene de Calcitonina/farmacologia , Proteína Semelhante a Receptor de Calcitonina/agonistas , Mióticos/farmacologia , Modelos Moleculares , Fragmentos de Peptídeos/farmacologia , Proteína 1 Modificadora da Atividade de Receptores/metabolismo , Receptores de Peptídeo Relacionado com o Gene de Calcitonina/agonistas , Transdução de Sinais/efeitos dos fármacos , Substituição de Aminoácidos , Animais , Sítios de Ligação , Ligação Competitiva , Células COS , Peptídeo Relacionado com Gene de Calcitonina/química , Peptídeo Relacionado com Gene de Calcitonina/genética , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Proteína Semelhante a Receptor de Calcitonina/química , Proteína Semelhante a Receptor de Calcitonina/genética , Proteína Semelhante a Receptor de Calcitonina/metabolismo , Chlorocebus aethiops , Cinética , Ligantes , Mióticos/química , Mióticos/metabolismo , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/metabolismo , Mutação Puntual , Conformação Proteica , Domínios e Motivos de Interação entre Proteínas , Mapeamento de Interação de Proteínas , Multimerização Proteica , Proteína 1 Modificadora da Atividade de Receptores/química , Proteína 1 Modificadora da Atividade de Receptores/genética , Receptores de Peptídeo Relacionado com o Gene de Calcitonina/química , Receptores de Peptídeo Relacionado com o Gene de Calcitonina/genética , Receptores de Peptídeo Relacionado com o Gene de Calcitonina/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/farmacologia , Homologia Estrutural de Proteína
3.
Biochem J ; 474(12): 1981-1992, 2017 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-28455390

RESUMO

Transport of bile acids across the basolateral membrane of the intestinal enterocyte is carried out by the organic solute transporter (Ost) composed of a seven-transmembrane domain (TMD) subunit (Ostα) and an ancillary single TMD subunit (Ostß). Although previous investigations have demonstrated the importance of the TMD of Ostß for its activity, further studies were conducted to assess the contributions of other regions of the Ostß subunit. Transport activity was retained when Ostß was truncated to contain only the TMD with 15 additional residues on each side and co-expressed with Ostα, whereas shorter fragments were inactive. To probe the broader functions of Ostß segments, chimeric proteins were constructed in which N-terminal, TMD or C-terminal regions of Ostß were fused to corresponding regions of receptor activity-modifying protein (RAMP1), a single TMD protein required by several seven-TMD G-protein-coupled receptors including the calcitonin receptor-like receptor (CLR). Ostß/RAMP1 chimeras were expressed with Ostα and CLR. As expected, replacing the Ostß TMD abolished transport activity; however, replacing either the entire N-terminal or entire C-terminal domain of Ostß with RAMP1 sequences did not prevent plasma membrane localization or the ability to support [3H]taurocholate uptake. Co-immunoprecipitation experiments revealed that the C-terminus of Ostß is a previously unrecognized site of interaction with Ostα. All chimeras containing N-terminal RAMP1 segments allowed co-expressed CLR to respond to agonists with strong increases in cyclic AMP. These results provide new insights into the structure and function of the heteromeric Ost transporter complex.


Assuntos
Ácidos e Sais Biliares/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Absorção Fisiológica/efeitos dos fármacos , Animais , Transporte Biológico/efeitos dos fármacos , Peptídeo Relacionado com Gene de Calcitonina/genética , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Proteína Semelhante a Receptor de Calcitonina/agonistas , Proteína Semelhante a Receptor de Calcitonina/genética , Proteína Semelhante a Receptor de Calcitonina/metabolismo , AMP Cíclico/metabolismo , Células HEK293 , Humanos , Imunoprecipitação , Proteínas de Membrana Transportadoras/química , Proteínas de Membrana Transportadoras/genética , Camundongos , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/metabolismo , Domínios e Motivos de Interação entre Proteínas , Transporte Proteico , Proteína 1 Modificadora da Atividade de Receptores/química , Proteína 1 Modificadora da Atividade de Receptores/genética , Proteína 1 Modificadora da Atividade de Receptores/metabolismo , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/metabolismo , Sistemas do Segundo Mensageiro/efeitos dos fármacos , Homologia Estrutural de Proteína , Ácido Taurocólico/metabolismo , Trítio
4.
Biol Reprod ; 91(3): 65, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25061099

RESUMO

Accumulating data suggest that adrenomedullin (ADM) regulates the trophoblast cell growth, migration, and invasion. However, the effect of ADM on trophoblast differentiation is poorly understood. In this study, we hypothesized that ADM promotes the differentiation of trophoblast stem cells (TSCs) into trophoblast giant cells (TGCs). Using rat TSCs, Rcho-1 cells, we investigated the effect of ADM on TSC differentiation into TGCs in differentiation or stem cell media, respectively, and explored the effect of ADM on the mechanistic target of rapamycin (MTOR) signaling in trophoblast cell differentiation. The results include: 1) in the presence of differentiation medium, 10⁻7 M ADM, but not lower doses, elevated (P < 0.05) Prl3b1/Esrrb (i.e., the ratio of mRNA levels) by 1.7-fold compared to that in control; 2) the supplementation of ADM antagonist, regardless of the concentration of ADM, reduced (P < 0.05) Prl3b1/Esrrb by 2-fold, compared to control group, while the supplementation of CGRP antagonist, regardless of the concentration of ADM, did not change Prl3b1/Esrrb; 3) in the presence of stem cell medium, ADM did not alter the expression of TSC and TGC marker genes, however, the ratio of Prl3b1/Esrrb was reduced (P < 0.05) by ADM antagonist compared to that in control; and 4) ADM increased (P < 0.05) phosphorylated MTOR proteins and the ratio of phosphorylated to total MTOR proteins by 2.0- and 1.7-fold, respectively. The results indicate that ADM promotes but does not induce the differentiation of TSCs to TGCs in a dose-dependent manner and MTOR signaling may play a role in this process.


Assuntos
Adrenomedulina/metabolismo , Proteína Semelhante a Receptor de Calcitonina/agonistas , Proteína 2 Modificadora da Atividade de Receptores/agonistas , Receptores de Adrenomedulina/agonistas , Transdução de Sinais , Células-Tronco/metabolismo , Trofoblastos/metabolismo , Adrenomedulina/antagonistas & inibidores , Adrenomedulina/farmacologia , Animais , Antígenos de Diferenciação/metabolismo , Biomarcadores/metabolismo , Peptídeo Relacionado com Gene de Calcitonina/farmacologia , Proteína Semelhante a Receptor de Calcitonina/antagonistas & inibidores , Proteína Semelhante a Receptor de Calcitonina/metabolismo , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Tamanho Celular/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Fragmentos de Peptídeos/farmacologia , Fosforilação/efeitos dos fármacos , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Ratos , Proteína 2 Modificadora da Atividade de Receptores/metabolismo , Receptores de Adrenomedulina/antagonistas & inibidores , Receptores de Adrenomedulina/metabolismo , Transdução de Sinais/efeitos dos fármacos , Células-Tronco/citologia , Células-Tronco/efeitos dos fármacos , Serina-Treonina Quinases TOR/química , Serina-Treonina Quinases TOR/metabolismo , Trofoblastos/citologia , Trofoblastos/efeitos dos fármacos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA