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1.
Diagnostics (Basel) ; 10(9)2020 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-32962217

RESUMO

Peripheral arterial disease (PAD) is a common manifestation of generalized atherosclerosis, which affects more than 200 million patients worldwide. Currently, there is no ideal biomarker for PAD risk stratification and diagnosis. The goal of this research was to investigate the levels of inflammation biomarkers and cystatin C and to explore their utility for the diagnosis of PAD. The study included 296 participants, distributed in two groups: 216 patients diagnosed with PAD and 80 patients without PAD as controls. All studied biomarker levels (C-reactive protein, CRP; fibrinogen; erythrocyte sedimentation rate, ESR; neopterin; beta 2-microglobulin, B2-MG; and cystatin C) were significantly higher in the PAD group and indirectly correlated with the ankle-brachial index (ABI). The final logistic regression model included an association of neopterin, fibrinogen, and cystatin C as the most efficient markers for the prediction of PAD diagnosis. When comparing the area under the curve (AUC) for all biomarkers, the value for neopterin was significantly higher than those of all the other analyzed biomarkers. In agreement with previous studies, this research shows that markers such as fibrinogen, CRP, ESR, B2-MG, and cystatin C have significant value for the diagnosis of PAD, and also clearly underlines the accuracy of neopterin as a leading biomarker in PAD prediction.

2.
Medicina (Kaunas) ; 55(7)2019 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-31269687

RESUMO

Background and objectives: The etiology of anemia associated with heart failure is not fully understood, but there are data suggesting the involvement of multiple mechanisms, including various drug therapies used in patients with heart failure. Our primary objective was to evaluate the impact of beta blockers, angiotensin-converting enzyme inhibitors, and calcium-channel blockers on iron metabolism in patients with heart failure. Materials and Methods: This was a prospective observational study that included patients diagnosed with heart failure and iron deficiency (defined by ferritin <100 µg/L, or 100-300 µg/L with transferrin saturation <20%). Patients with anemia secondary to a known cause were excluded. Results: We found a statistically significant correlation between beta-blocker treatment and ferritin values (p = 0.02). Iron, hemoglobin, and hematocrit levels were significantly lower in the patients using calcium-channel blockers than those who were not. We also found a statistically significant indirect correlation (p = 0.04) between the use of angiotensin-converting enzyme inhibitors and hematocrit levels. Conclusion: The contribution of our study arises from the additional data regarding the drug-induced etiology of iron deficiency. Practitioners should be aware of the potential impact of therapeutic recommendations and this should imply a close monitoring of the biochemical parameters of iron deficiency in this category of patients.


Assuntos
Anemia/etiologia , Insuficiência Cardíaca/tratamento farmacológico , Distúrbios do Metabolismo do Ferro/etiologia , Antagonistas Adrenérgicos beta/efeitos adversos , Antagonistas Adrenérgicos beta/uso terapêutico , Idoso , Anemia/sangue , Anemia/complicações , Inibidores da Enzima Conversora de Angiotensina/efeitos adversos , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Bloqueadores dos Canais de Cálcio/efeitos adversos , Bloqueadores dos Canais de Cálcio/uso terapêutico , Feminino , Insuficiência Cardíaca/sangue , Humanos , Ferro/análise , Ferro/sangue , Distúrbios do Metabolismo do Ferro/sangue , Masculino , Pessoa de Meia-Idade
3.
J Int Med Res ; 47(1): 159-172, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30222016

RESUMO

OBJECTIVE: This study was performed to determine whether a dual-biomarker approach using N-terminal prohormone of brain natriuretic peptide (NT-proBNP) and galectin-3 optimizes the diagnosis and risk stratification of acute cardiac dyspnea. Atypical clinical manifestations and overlapping pathologies require objective and effective diagnostic methods to avoid treatment delays. METHODS: This prospective observational study included 208 patients who presented to the emergency department for acute dyspnea. NT-proBNP and galectin-3 were measured upon admission. The patients were divided into two groups according to the etiology of their clinical manifestations: cardiac and non-cardiac dyspnea. The patients' New York Heart Association functional class, left ventricular ejection fraction, and discharge status were assessed. RESULTS: Diagnostic criteria for acute heart failure were fulfilled in 61.1% of the patients. NT-proBNP and galectin-3 were strongly and significantly correlated. Receiver operating characteristic analysis revealed similar areas under the curve for both markers in the entire group of patients as well as in the high-risk subsets of patients. CONCLUSIONS: The diagnostic performance of NT-proBNP and galectin-3 is comparable for both the total population and high-risk subsets. Galectin-3 adds diagnostic value to the conventional NT-proBNP in patients with acute cardiac dyspnea, and its utility is of major interest in uncertain clinical situations.


Assuntos
Dispneia/diagnóstico , Galectina 3/sangue , Insuficiência Cardíaca/diagnóstico , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Doença Aguda , Adulto , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Biomarcadores/sangue , Proteínas Sanguíneas , Dispneia/sangue , Dispneia/fisiopatologia , Serviço Hospitalar de Emergência , Feminino , Galectinas , Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/fisiopatologia , Ventrículos do Coração/metabolismo , Ventrículos do Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Curva ROC , Volume Sistólico/fisiologia
4.
Sci Rep ; 6: 21228, 2016 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-26888314

RESUMO

Myocardial hypertrophy is an adaptive response to hemodynamic demands. Although angiogenesis is critical to support the increase in heart mass with matching blood supply, it may also promote a hypertrophic response. Previously, we showed that cardiac angiogenesis induced by placental growth factor (PlGF), promotes myocardial hypertrophy through the paracrine action of endothelium-derived NO, which triggers the degradation of regulator of G protein signaling 4 (RGS4) to activate the Akt/mTORC1 pathways in cardiomyocytes. Here, we investigated whether miRNAs contribute to the development of hypertrophic response associated with myocardial angiogenesis. We show that miR-182 is upregulated concurrently with the development of hypertrophy in PlGF mice, but not when hypertrophy was blocked by concomitant expression of PlGF and RGS4, or by PlGF expression in eNOS(-/-) mice. Anti-miR-182 treatment inhibits the hypertrophic response and prevents the Akt/mTORC1 activation in PlGF mice and NO-treated cardiomyocytes. miR-182 reduces the expression of Bcat2, Foxo3 and Adcy6 to regulate the hypertrophic response in PlGF mice. Particularly, depletion of Bcat2, identified as a new miR-182 target, promotes Akt(Ser473)/p70-S6K(Thr389) phosphorylation and cardiomyocyte hypertrophy. LV pressure overload did not upregulate miR-182. Thus, miR-182 is a novel target of endothelial-cardiomyocyte crosstalk and plays an important role in the angiogenesis induced-hypertrophic response.


Assuntos
Cardiomegalia/metabolismo , Endotélio/metabolismo , MicroRNAs/biossíntese , Miócitos Cardíacos/metabolismo , Neovascularização Patológica/metabolismo , Regulação para Cima , Animais , Cardiomegalia/genética , Cardiomegalia/patologia , Endotélio/patologia , Alvo Mecanístico do Complexo 1 de Rapamicina , Proteínas de Membrana , Camundongos , Camundongos Knockout , MicroRNAs/genética , Complexos Multiproteicos/genética , Complexos Multiproteicos/metabolismo , Miócitos Cardíacos/patologia , Neovascularização Patológica/genética , Neovascularização Patológica/patologia , Óxido Nítrico/genética , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo III/genética , Óxido Nítrico Sintase Tipo III/metabolismo , Proteínas/genética , Proteínas/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas RGS/genética , Proteínas RGS/metabolismo , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo
5.
Open Med (Wars) ; 10(1): 278-284, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-28352706

RESUMO

OBJECTIVES: The objective of this study was to assess the pattern and outcome of acute cholinesterase inhibitors substances (CIS) poisoning cases, in a cohort from a regional tertiary care hospital. METHODS: cases admitted in the Toxicology Clinic of "Sf. Spiridon" Emergency Clinic Hospital Iasi, Romania between 1983 and 2013 were studied. RESULTS: a total number of 606 patients were included. The reason for exposures was intentional in 70% of cases and the commonest route of poisoning was oral in 92.2%. The highest percent of cases was females (56.4), the age group 20-29 (25.4%) and the majority (66.7%) coming from rural areas, 28.2% being agricultural workers. 36.6% of cases were severe clinical forms. Overall mortality rates were 3.8%, more than half of the death patients (65.2%) had concomitant alcohol intake. It was a significant statistical association between decrease level of serum cholinesterase on admittance and severe forms (p 0.000) and between survival and deaths groups (p 0.000). The pattern of poisoning described by our retrospective study suggests that CIS poisoning are mainly preventable. The main effective goals for prevention are restriction in free accessibility to toxic pesticides, together with sustained efforts in education concerning the life-threatening danger of pesticide poisoning.

6.
Circ Cardiovasc Imaging ; 7(1): 92-9, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24170237

RESUMO

BACKGROUND: A standard quantitative imaging approach to evaluate peripheral arterial disease does not exist. Quantitative tools for evaluating arteriogenesis in vivo are not readily available, and the feasibility of monitoring serial regional changes in lower extremity perfusion has not been examined. METHODS AND RESULTS: Serial changes in lower extremity arteriogenesis and muscle perfusion were evaluated after femoral artery occlusion in a porcine model using single photon emission tomography (SPECT)/CT imaging with postmortem validation of in vivo findings using gamma counting, postmortem imaging, and histological analysis. Hybrid 201Tl SPECT/CT imaging was performed in pigs (n=8) at baseline, immediately postocclusion, and at 1 and 4 weeks postocclusion. CT imaging was used to identify muscle regions of interest in the ischemic and nonischemic hindlimbs for quantification of regional changes in CT-defined arteriogenesis and quantification of 201Tl perfusion. Four weeks postocclusion, postmortem tissue 201Tl activity was measured by gamma counting, and immunohistochemistry was performed to assess capillary density. Relative 201Tl retention (ischemic/nonischemic) was reduced immediately postocclusion in distal and proximal muscles and remained lower in calf and gluteus muscles 4 weeks later. Analysis of CT angiography revealed collateralization at 4 weeks within proximal muscles (P<0.05). SPECT perfusion correlated with tissue gamma counting at 4 weeks (P=0.01). Increased capillary density was seen within the ischemic calf at 4 weeks (P=0.004). CONCLUSIONS: 201Tl SPECT/CT imaging permits serial, regional quantification of arteriogenesis and resting tissue perfusion after limb ischemia. This approach may be effective for detection of disease and monitoring therapy in peripheral arterial disease.


Assuntos
Extremidade Inferior/irrigação sanguínea , Imagem Multimodal/métodos , Neovascularização Fisiológica , Doença Arterial Periférica/diagnóstico , Tomografia Computadorizada de Emissão de Fóton Único , Tomografia Computadorizada por Raios X , Animais , Artérias/diagnóstico por imagem , Artérias/fisiopatologia , Capilares/diagnóstico por imagem , Capilares/fisiopatologia , Circulação Colateral , Modelos Animais de Doenças , Masculino , Imagem de Perfusão , Doença Arterial Periférica/fisiopatologia , Valor Preditivo dos Testes , Fluxo Sanguíneo Regional , Reprodutibilidade dos Testes , Suínos
7.
Int J Toxicol ; 32(5): 351-7, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24055824

RESUMO

The main objective of this study was to investigate whether cardiac troponin (cTn) and N-terminal, protein B-type natriuretic peptide (NT-proBNP) can be useful as indicators for amitriptyline cardiotoxicity which is a known drug having sublethal toxic cardiac effects. At the same time, this study looked at detecting potential histopathological changes specific to irreversible cardiac injuries in a rat model of amitriptyline cardiotoxicity. Male Wistar rats were randomly divided into 2 groups, control (saline) group and amitriptyline group (100 mg/kg body weight intraperitoneally, equivalent for lethal dose at 50%). Blood was collected 30 minutes after the administration. The cTn was measured using 3 different methods (2 methods designed for human use and a sandwich enzyme immunoassay specific for rat cTnT). The brain natriuretic peptide was measured by 2 different methods (1 for human and 1 specific for rats). Electrocardiography showed that the QRS complex (P < .0001) and the QT interval (P = .002) were significantly prolonged for amitriptyline-treated animals. Troponin T and NT-proBNP had significantly increased levels in all the rats but showed positive results only when using rat-specific quantitative measurement. In certain rats, the histopathological examination identified a few small foci of acute myocardial necrosis. In conclusion, elevation of cTnT and NT-proBNP are early indicators of cardiotoxicity, yet the significance of irreversible myocardial damage in amitriptyline cardiotoxicity needs to be further understood.


Assuntos
Amitriptilina/efeitos adversos , Antidepressivos Tricíclicos/efeitos adversos , Cardiopatias/sangue , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Troponina T/sangue , Animais , Biomarcadores/sangue , Coração/fisiopatologia , Cardiopatias/induzido quimicamente , Cardiopatias/fisiopatologia , Síndrome do QT Longo/sangue , Síndrome do QT Longo/induzido quimicamente , Síndrome do QT Longo/fisiopatologia , Masculino , Miocárdio/metabolismo , Miocárdio/patologia , Ratos , Ratos Wistar
8.
J Clin Invest ; 123(4): 1718-31, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23454748

RESUMO

Myocardial hypertrophy is an adaptation to increased hemodynamic demands. An increase in heart tissue must be matched by a corresponding expansion of the coronary vasculature to maintain and adequate supply of oxygen and nutrients for the heart. The physiological mechanisms that underlie the coordination of angiogenesis and cardiomyocyte growth are unknown. We report that induction of myocardial angiogenesis promotes cardiomyocyte growth and cardiac hypertrophy through a novel NO-dependent mechanism. We used transgenic, conditional overexpression of placental growth factor (PlGF) in murine cardiac tissues to stimulate myocardial angiogenesis and increase endothelial-derived NO release. NO production, in turn, induced myocardial hypertrophy by promoting proteasomal degradation of regulator of G protein signaling type 4 (RGS4), thus relieving the repression of the Gßγ/PI3Kγ/AKT/mTORC1 pathway that stimulates cardiomyocyte growth. This hypertrophic response was prevented by concomitant transgenic expression of RGS4 in cardiomyocytes. NOS inhibitor L-NAME also significantly attenuated RGS4 degradation, and reduced activation of AKT/mTORC1 signaling and induction of myocardial hypertrophy in PlGF transgenic mice, while conditional cardiac-specific PlGF expression in eNOS knockout mice did not induce myocardial hypertrophy. These findings describe a novel NO/RGS4/Gßγ/PI3Kγ/AKT mechanism that couples cardiac vessel growth with myocyte growth and heart size.


Assuntos
Crescimento Celular , Miócitos Cardíacos/fisiologia , Neovascularização Fisiológica , Óxido Nítrico/fisiologia , Proteínas RGS/metabolismo , Adaptação Biológica , Animais , Células Cultivadas , Vasos Coronários/fisiologia , Endotélio Vascular/metabolismo , Endotélio Vascular/fisiologia , Ventrículos do Coração/citologia , Ventrículos do Coração/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Complexos Multiproteicos , Miócitos Cardíacos/efeitos dos fármacos , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase/metabolismo , Fator de Crescimento Placentário , Proteínas da Gravidez/fisiologia , Proteínas/metabolismo , Proteólise , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais , Serina-Treonina Quinases TOR
9.
Circulation ; 126(22): 2589-600, 2012 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-23091063

RESUMO

BACKGROUND: Arteriogenesis and collateral formation are complex processes requiring integration of multiple inputs to coordinate vessel branching, growth, maturation, and network size. Factors regulating these processes have not been determined. METHODS AND RESULTS: We used an inhibitor of NFκB activation (IκBαSR) under control of an endothelial-specific inducible promoter to selectively suppress endothelial nuclear factor-κB activation during development, in the adult vasculature, or in vitro. Inhibition of nuclear factor-κB activation resulted in formation of an excessively branched arterial network that was composed of immature vessels and provided poor distal tissue perfusion. Molecular analysis demonstrated reduced adhesion molecule expression leading to decreased monocyte influx, reduced hypoxia-inducible factor-1α levels, and a marked decrease in δ-like ligand 4 expression with a consequent decrease in Notch signaling. The latter was the principal cause of increased vascular branching as treatment with Jagged-1 peptide reduced the size of the arterial network to baseline levels. CONCLUSIONS: These findings identify nuclear factor-κB as a key regulator of adult and developmental arteriogenesis and collateral formation. Nuclear factor-κB achieves this by regulating hypoxia-inducible factor-1α-dependent expression of vascular endothelial growth factor-A and platelet-derived growth factor-BB, which are necessary for the development and maturation of the arterial collateral network, and by regulating δ-like ligand 4 expression, which in turn determines the size and complexity of the network.


Assuntos
Células Endoteliais/metabolismo , Isquemia/fisiopatologia , Subunidade p50 de NF-kappa B/metabolismo , Neovascularização Patológica/fisiopatologia , Neovascularização Fisiológica/fisiologia , Animais , Animais Recém-Nascidos , Becaplermina , Encéfalo/metabolismo , Modelos Animais de Doenças , Membro Posterior/irrigação sanguínea , Células Endoteliais da Veia Umbilical Humana , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Isquemia/metabolismo , Camundongos , Camundongos Transgênicos , Subunidade p50 de NF-kappa B/genética , Neovascularização Patológica/metabolismo , Proteínas Proto-Oncogênicas c-sis/metabolismo , Retina/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
10.
Rev Med Chir Soc Med Nat Iasi ; 115(2): 470-6, 2011.
Artigo em Romano | MEDLINE | ID: mdl-21870743

RESUMO

Inflammation is a fundamental biologic process evolutionally preserved by a germ line code. The interplay of the epigenetic with the environment directs the code to temporally distinct inflammatory responses, which can be acute or chronic. The aim of this study is to present new aspects regarding the resolution of inflammation. Acute inflammation normally resolves by mechanisms still somewhat elusive. Current evidence suggests that an active coordinated program initiated the first few hours after the inflammatory response begins and its failure lead to chronic inflammation. This process is essential for appropriate host responses, tissue protection and the return to homeostasis. Prostaglandins and leukotrienes are lipid mediators that play important roles in host defense and acute inflammation. Granulocytes promote the switch of arachidonic acid-derived prostaglandins and leukotrienes to lipoxins, active antiinflammatory and pro-resolution mediators. The apoptosis of the neutrophils coincides with the biosynthesis of resolvins and protectins from omega-3 polyunsaturated fatty acids and releases anti-inflammatory and reparative cytokines. This information could lead to new treatments for inflammatory diseases.


Assuntos
Anti-Inflamatórios/farmacologia , Mediadores da Inflamação/imunologia , Inflamação/tratamento farmacológico , Inflamação/imunologia , Anti-Inflamatórios/uso terapêutico , Antígenos CD59/farmacologia , Antígenos CD59/uso terapêutico , Doença Crônica , Ácidos Docosa-Hexaenoicos/farmacologia , Ácidos Docosa-Hexaenoicos/uso terapêutico , Glucocorticoides/farmacologia , Glucocorticoides/uso terapêutico , Humanos , Inflamação/metabolismo , Inflamação/prevenção & controle , Lipoxinas/farmacologia , Lipoxinas/uso terapêutico , Superóxido Dismutase/farmacologia , Superóxido Dismutase/uso terapêutico , Resultado do Tratamento
11.
Hum Exp Toxicol ; 30(12): 1896-903, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21427138

RESUMO

The aim of this retrospective epidemiological study was to investigate the demographical, etiological and clinical characteristics of acute drug poisonings in Iasi County, Romania. All patients were referred and admitted in the Toxicology Clinic of "Sf. Ioan" Emergency Clinic Hospital Iasi, Romania. Between 2003 and 2009, 811 cases of acute drug poisonings were recorded, counting for 28.43% from the total number of poisonings. The majority of these poisonings resulted in mild (51.94%) and medium (28.35%) clinical forms, while 19.71% were coma situations. In all, 63.51% of patients originated from urban areas, 39.94% were unemployed and the patients were predominantly women (66.46%). A high percentage (97.27%) were suicide attempts, using only one type of drug (65.88%) and the 21-30 years group (29.8%) records the highest incidence, for both women and men. The most frequently involved drugs were benzodiazepines 13.69%, anticonvulsive drugs 8.63%, barbiturates 8.51% and cardiovascular drugs 5.92%. Drugs combinations were recorded in 32.92% of cases and 1.2% were combinations between drugs and other substances. Mortality was the outcome in 0.3% of the total registered number of acute drug poisonings. This study underlines that in order to provide a proper management of these situations, a Regional Poison Information Center is absolutely necessary.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Exposição Ambiental/efeitos adversos , Intoxicação/etiologia , Doença Aguda , Adolescente , Adulto , Distribuição por Idade , Idoso , Causas de Morte , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Intoxicação/epidemiologia , Polimedicação , Estudos Retrospectivos , Romênia/epidemiologia , Tentativa de Suicídio , Adulto Jovem
12.
J Mater Sci Mater Med ; 21(11): 3009-18, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20820886

RESUMO

Ketoprofen (Ket) was intercalated into layered double hydroxides (ZnAlLDH and MgAlLDH) using the ionic exchange method. The drug intercalation was confirmed by X-ray diffraction (XRD) and FTIR spectroscopy. Ket release from the inorganic matrix was studied at pH 7.4 in continuous regime with a flow rate of 0.5 and respectively 1.0 ml/min. The kinetical data were interpreted using the Ritger and Peppas model. The data prove that the release kinetics and mechanism depend on the eluent flow rate. Quantification of gastric tolerance shows that the ulcerogenic effect of the intercalated drug is lower than the one of the raw Ket. The antinociceptive effect of both formulations was studied by the hot-plate method performed on mice. The MgAlLDH_Ket formulation shows a tendency towards a stronger antinociceptive effect than its ZnAlLDH_Ket counterpart during the 210 min recorded period.


Assuntos
Química Farmacêutica/métodos , Portadores de Fármacos/química , Hidróxidos/química , Cetoprofeno/farmacocinética , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/efeitos adversos , Anti-Inflamatórios não Esteroides/farmacocinética , Portadores de Fármacos/metabolismo , Trato Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/patologia , Hidróxidos/metabolismo , Cetoprofeno/administração & dosagem , Cetoprofeno/efeitos adversos , Masculino , Camundongos , Medição da Dor , Polímeros/química , Polímeros/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Úlcera Gástrica/induzido quimicamente , Úlcera Gástrica/epidemiologia , Resultado do Tratamento , Difração de Raios X
13.
Rom J Physiol ; 41(1-2): 119-26, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15984662

RESUMO

The aim of this study was to investigate the importance of the amino acidic sequence at N-terminal end of certain minimum structure enkephalin-like peptides for the analgesic activity. Different groups of mice or rats were treated with 1) L-tyrosine (i.p. 200 mg/kg), 2) Tyr-Phe (i.t. 0.5 mg/rat), 3) Tyr-Pro-Phe (i.t. 0.5 mg/rat), 4) Gly-Tyr (i.t. 0.5 mg/rat), 5) Tyr-Gly-Gly (i.t. 0.5 mg/rat). Different tests were utilized to evaluate the antinociceptive effect of the substances tested: thermal nociception (hot plate test, plantar test), mechanical nociception (analgesymeter test). Tyr-Pro-Phe, Tyr-Gly-Gly, Tyr-Phe, but not Gly-Tyr, elicited analgesic activity. So, the presumption made in the case of atypical opioid peptides that opioid-like activity in case of peptides presumes a tyrosine residue at the N-terminal sequence, applies for shorter peptides. It appears also that minimal structure brain peptides with an N-terminal Tyr-Pro, rather than the Tyr-Gly-Gly-Phe sequence typical of other endogenous opioids, can provide better affinity for the opioid receptors and stronger analgesic activity. The inhibition of their analgesic effect by previous administration of naloxone proves that this effect is mediated through the endogenous opioid system.


Assuntos
Analgésicos Opioides/química , Analgésicos Opioides/farmacologia , Encefalinas/genética , Encefalinas/farmacologia , Nociceptores/efeitos dos fármacos , Sequência de Aminoácidos , Analgésicos Opioides/administração & dosagem , Animais , Encefalinas/administração & dosagem , Injeções Espinhais , Camundongos , Medição da Dor , Ratos , Ratos Wistar
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