RESUMO
Digital loop-mediated isothermal amplification (digital LAMP, dLAMP) is a novel nucleic acid amplification technique developed in recent years. It divides the target nucleic acid and LAMP reagent into a large number of independent detection regions, and uses a highly active chain replacement DNA polymerase and four specially designed primers for rapid amplification under isothermal conditions, which provides a good platform for quantitative detection of target nucleic acids. The advantages of high accuracy, high sensitivity, absolute quantification, high tolerance to inhibitors and simple instrumentation make the dLAMP technique very promising in molecular diagnosis, especially in rapid detection of pathogenic microorganisms, it shows a good application prospect in the fields of clinical diagnosis, food safety and environmental monitoring. Certainly, the development of dLAMP still faces some challenges, such as how to avoid non-specific amplification in multiple primer designs, multi-target nucleic acids and simultaneous detection of a large number of samples. With the development of dLAMP technology, this technology will greatly enrich the future development of molecular diagnostics. Applying rapid and effective molecular diagnostic techniques to the diagnosis of pathogenic microorganisms has important social significance for disease prevention and control.
Assuntos
Técnicas de Diagnóstico Molecular , Técnicas de Amplificação de Ácido Nucleico , Humanos , Sensibilidade e Especificidade , TecnologiaRESUMO
Allergic diseases have continued to increase year by year causing serious physical and mental injury to patients, families and individuals. This increase has been driven by conventional environmental and nutritional changes but is also created by the continual introduction of food additives into the diet and novel interior decoration materials into the living space. The causes of allergic diseases are complex and diverse, and the medical laboratory often is not be able to identify the allergic trigger; this creates a difficult environment to identify the appropriate clinical treatment for disease prevention and control. Physicians must be able to identify these triggers to help patients avoid the underlying allergenic cause of their disease. This can only be done by actively knowing a patient's medical history, identifying the clinical manifestations of hypersensitivity and utilizing confirmatory testing as an important clinical tool in identifying the allergic source.
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Hipersensibilidade Alimentar , Hipersensibilidade , Alérgenos , Dieta , Hipersensibilidade Alimentar/diagnóstico , Humanos , Hipersensibilidade/diagnósticoRESUMO
Objective: To analyze the antibody levels and dynamic changes in patients infected with 2019-novel coronavirus(2019-nCoV). Methods: The average age of 72 corona virus disease 2019 (COVID-19) patients was (45.53±16.74)years(median age:47 year), including (44.88±17.09) years(median age:46 year) for 38 males and (46.32±16.52)years (median age:46 year) for 34 females in Loudi City, Hunan Province. There is no significant difference in genders between the severe and mild groups (χ²=0.916, P>0.05). There is a significant difference in the age between the severe and mild groups (F=3.315, P<0.05). The blood samples of 72 discharged patients were collected and the consistence of IgM and IgG antibodies were detected by chemiluminescence method. SPSS25.0 was used for gender, age, case type and antibody analysis of variance, χ2 test and other analysis. Results: The average time of the serum samples collection of 72 patients was (34.89±9.02)days (median time: 34 days) from onset of COVID-19, and (14.53±8.35) days (median time: 14 days) from discharge. The positive rate of IgM or IgG was 97.22% (70/72), and the positive rate of IgM and IgG was 48.61% (35/72) and 97.22% (70/72) respectively. Serum COVID-19 antibodies were detected in 72 patients from 1st to 40th days after discharge. The average concentration of IgM in 1-7 days, 8-14 days, 15-21 days, 22-28 days, above 29 days were 21.91(7.07-52.84)AU/ml, 14.16(6.19-32.88)AU/ml, 11.36(6.65-42.15)AU/ml, 8.15(3.66-30.12)AU/ml, 2.98(0.46-6.37)AU/ml. There was no significant difference in the time of IgM antibody concentration (H= 8.439, P>0.05). The average concentrations of IgG in 1-7 days, 8-14 days, 15-21 days, 22-28 days, 29 days and above were 169.90 (92.06-190.91) AU/ml, 163.89 (91.19-208.02) AU/ml, 173.31 (95.06-191.28) AU/ml, 122.84 (103.19-188.34) AU/ml, 101.98 (43.75-175.30) AU/ml, respectively, (H=2.232, P>0.05). The IgM becomes negative after the 3rd week of discharge and decreases rapidly with time. The IgG concentration higher than IgM during the same period, and keep at high level without any change, and decrease in the fourth week. Among them, 5 cases developed "re-infection" within 1-3 weeks after discharge, and the rate of "re-infection" was 6.94% (5/72 cases). Conclusions: After the COVID-19 patients are discharged from the hospital, the level of antibodies produced varies greatly among individuals, but the overall changes in antibodies have a certain pattern. It is recommended to strengthen the antibody monitoring during hospitalization and after discharge from the hospital to reduce the "re-infection" rate and potential risk of infection.
Assuntos
COVID-19 , Adulto , Anticorpos Antivirais , Feminino , Humanos , Imunoglobulina G , Imunoglobulina M , Masculino , Pessoa de Meia-Idade , SARS-CoV-2RESUMO
Fluorescence imaging signal is severely limited by the quantum efficiency and emission wavelength. To overcome these challenges, novel NIR-emitting K5NdLi2F10 nanoparticles under NIR excitation was introduced as fluorescence imaging probe for the first time. The photostability of K5NdLi2F10 nanoparticles in the water, phosphate buffer saline, fetal bovine serum and living mice was investigated. The fluorescence signal was detected with depths of 3.5 and 2.0 cm in phantom and pork tissue, respectively. Fluorescence spectrum with a significant signal-to-background ratio of 10:1 was captured in living mice. Moreover, clear NIR images were virtualized for the living mice after intravenous injection. The imaging ability of nanoparticles in tumor-beard mice were evaluated, the enrichment of K5NdLi2F10 nanoparticles in tumor site due to the enhanced permeability and retention effect was confirmed. The systematic studies of toxicity, bio-distribution and in-vivo dynamic imaging suggest that these materials give high biocompatibility and low toxicity. These NIR-emitting nanoparticles with high quantum efficiency, high penetration and low toxicity might facilitate tumor identification in deep tissues more sensitively.
Assuntos
Diagnóstico por Imagem/métodos , Raios Infravermelhos , Nanoestruturas/química , Teoria Quântica , Animais , Sobrevivência Celular , Eritrócitos/citologia , Feminino , Células HeLa , Hemólise , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanoestruturas/toxicidade , Nanoestruturas/ultraestrutura , Imagem Óptica , Especificidade de Órgãos , Imagens de Fantasmas , Ratos Sprague-Dawley , Espectrometria de Fluorescência , SuínosRESUMO
Short rib-polydactyly syndrome type III (SRPS3) is a perinatal lethal skeletal disorder with polydactyly and multisystem organ abnormalities. While ultrasound of the fetus can detect skeletal abnormalities characteristic of SRPS3, the syndrome is often difficult to diagnose before birth. As SRPS3 is an autosomal recessive disorder, identification of the gene mutations involved could lead to the development of prenatal genetic testing as an accurate method of diagnosis. In this study, we describe genetic screening approaches to identify potential abnormalities associated with SRPS3. Karyotype analysis, array comparative genomic hybridization (aCGH), and next-generation panel sequencing were each performed on a fetus showing signs of the disorder, as well as on the mother and father. Karyotype and aCGH results revealed no abnormalities. However, next-generation panel sequencing identified novel mutations in the DYNC2H1 gene. The fetus was compound heterozygous for both a missense mutation c.8313A > T and a frameshift mutation c.10711_10714delTTTA in the DYNC2H1 gene, which were inherited from the mother and father, respectively. These variants were further confirmed using Sanger sequencing and have not been previously reported. Our study indicates the utility of using next-generation panel sequencing in screening for novel disease-associated mutations.
Assuntos
Hibridização Genômica Comparativa , Dineínas do Citoplasma/genética , Predisposição Genética para Doença , Síndrome de Costela Curta e Polidactilia/genética , Adulto , Feminino , Feto , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Cariótipo , Mutação , Linhagem , Síndrome de Costela Curta e Polidactilia/diagnóstico por imagem , Síndrome de Costela Curta e Polidactilia/patologiaRESUMO
Sepsis is one of the critical illnesses caused by burns, trauma, shock, infection, and so on. In patients with sepsis, vascular permeability is prone to develop through various pathophysiological mechanisms and thus could result in accumulation of tissue fluid, insufficient intravascular fluid, and finally cause septic shock and multiple organ dysfunction syndrome. Recent studies have shown that various factors and mediators involved in the regulation of vascular permeability in sepsis are expected to become targets for clinical treatment of sepsis. In this paper, we have reviewed the research advances on some molecules which are significantly associated with vascular permeability in sepsis, such as vascular endothelial growth factor, angiopoietin, sphingosine-1-phosphate, heparin-binding protein, and Slit2.
Assuntos
Sepse , Choque Séptico , Permeabilidade Capilar , Humanos , Insuficiência de Múltiplos Órgãos , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
Summary Inflammatory myofibroblastic tumorï¼IMTï¼ is a rare spindle neoplasm with malignant potentials of local invasion, recurrence and metastasis. Here, we present an extremely unusual case of the larynx IMT that was recurred three times and transformed into laryngeal squamous cell carcinoma.
Assuntos
Granuloma de Células Plasmáticas , Neoplasias Laríngeas , Laringe , Neoplasias de Tecido Muscular , Humanos , Recidiva Local de NeoplasiaRESUMO
OBJECTIVE: To observe the morphological changes in the testes and ovaries of adult 12th-generation Oncomelania hupensis bred for 12 winters in Weishan Lake areas. METHODS: The offspring of the adult O. hupensis snails bred in the Weishan Lake that were originated from the Yangzhou section of the Yangtze River was defined as the experiment group, while uninfected, adult O. hupensis snails captured from the marshland of the Yangzhou section of the Yangtze River served as the control group. Snails were dissected and intact testicular and ovarian specimens were sampled, routinely fixed, dehydrated, embedded, polymerized in an oven and sliced on an ultramicrotome. The sections were visualized under a transmission electron microscope, and the ultrastructure of the snail gonad was compared between the experiment and control groups. RESULTS: Transmission electron microscopy showed "9 + 2" microtubules on the transverse sections of the tails of sperm cells in the testes of male snails in the control group, with triangular acrosomes and spiral, dense nuclei seen in the tip, while in the experiment group, the "9 + 2" microtubules disappeared on the transverse sections of the tails of sperm cells in the testes of male snails, with low chromatin density found in the tip. Transmission electron microscopy revealed clear nucleolus and nuclear membranes in the ova of female snail ovaries, and displayed yolk body, liposomes and endoplasmic reticulum in the cytoplasm, bilayer twists of nuclear membrane and a uniform nucleolus in the control group, while in the experiment group, smooth nuclear membrane and unclear nucleolus were observed in the ova of female snail ovaries, with few contents seen within cells. CONCLUSIONS: Following breeding for 12 winters in the Weishan Lake, the 12th-generation O. hupensis snails fail to fully adapt to the natural environment in northern China, and the remarkable changes in the ultrastructure of the snail gonad may be a cause of gradual decline and even extinction of O. hupensis in the Weishan Lake areas.
Assuntos
Microscopia Eletrônica de Transmissão , Caramujos , Animais , Cruzamento , China , Gônadas/ultraestrutura , Lagos , Caramujos/ultraestruturaRESUMO
Two cases with piriform fossa cancer underwent larynx lateral wall repair surgery. Case 1: The patient was admitted to the hospital because of pharyngeal discomfort with swallowing pain for 2 months Electronic laryngoscopy revealed neoplasm in the left piriform fossa. Space occupying lesion in left piriform fossa and paranasal space was found in MRI scan. The pathological diagnosis of this patient was squamous cell squamous cell carcinoma (T2N1M0). Case 2: The patient was admitted to the hospital because of blood in the sputum for more than 1 year. The electronic laryngoscope suggested neoplasm in the pharyngeal space and left vocal cord paralysis.Soft tissue thickening of the oropharynx and hypopharyngeal right wall was found in MRI scan. The pathological diagnosis of this patient was squamous cell carcinoma (T1N2M0).
RESUMO
In the course of exploring the hybridization properties of glass DNA microarrays, multi-stranded DNA structures were observed that could not be accounted for by classical Watson-Crick base pairing. Non-denatured double-stranded DNA array elements were shown to hybridize to single-stranded (ss)DNA probes. Similarly, ssDNA array elements were shown to bind duplex DNA probes. This led to a series of experiments demonstrating the formation of multi-stranded DNA structures on the surface of microarrays. These structures were observed with a number of heterogeneous sequences, including both purine and pyrimidine bases, with shared sequence identity between the ssDNA and one of the duplex strands. Furthermore, we observed a strong binding preference near the ends of duplexes containing a 3'-homologous strand. We suggest that such binding interactions on cationic solid surfaces could serve as a model for a number of biological processes mediated through multi-stranded DNA.
Assuntos
DNA/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Modelos Genéticos , Conformação de Ácido Nucleico , Hibridização de Ácido Nucleico/métodos , Oligonucleotídeos/metabolismo , Reação em Cadeia da PolimeraseRESUMO
To explore the genes responsible for myocardial infarction and restenosis after percutaneous transluminal coronary angioplasty, we performed association studies of the polymorphisms of the angiotensinogen and angiotensin-converting enzyme (ACE) genes. In the first study, normotensive myocardial infarction patients (n = 103) and control subjects (n = 103), who were matched for established risk factors with the myocardial infarction patients, were randomly selected. The angiotensinogen-TT genotype (T indicates threonine instead of methionine at position 235) was more frequent in the myocardial infarction group than in the control group (P < .05). The ACE-DD genotype (D indicates a deletion polymorphism in intron 16) was also more frequent in the myocardial infarction group (P < .0001). The odds ratio estimated by the combined analysis of the angiotensinogen-TT and ACE-DD genotypes (11.2) was markedly increased compared with that estimated separately from the angiotensinogen-TT (1.75) or ACE-DD (4.43) genotype. In the second study, we investigated 91 consecutive patients with acute myocardial infarction who underwent successful direct angioplasty. Combined analysis showed that the angiotensinogen-TT genotype did not enhance the predictability of myocardial infarction from the ACE-DD genotype. In conclusion, the angiotensinogen-TT genotype is a predictor for myocardial infarction, as well as the ACE-DD genotype, and the combined analysis of the angiotensinogen-TT and ACE-DD genotypes further enhanced the predictability of myocardial infarction in Japanese, suggesting its future clinical usefulness.
Assuntos
Infarto do Miocárdio/genética , Angioplastia Coronária com Balão , Sequência de Bases , Genótipo , Humanos , Pessoa de Meia-Idade , Dados de Sequência Molecular , Infarto do Miocárdio/etiologia , Peptidil Dipeptidase A/genética , Fatores de RiscoRESUMO
OBJECTIVE: To determine the changes in serum angiotensin II (Ang II) and endothelin-1 levels induced by vanadium treatment of sugar-fed rats in order to investigate the relationship between changes in blood pressure and Ang II and endothelin-1 levels. METHODS: Male spontaneously hypertensive rats (SHR) were fed starch (control), sucrose, and sucrose plus vanadium compounds at various concentrations. The systolic blood pressure of the rats was estimated by tail-cuff plethysmography. Serum Ang II and endothelin-1 levels were measured by radioimmunoassay. RESULTS: There were increases in systolic blood pressure (by 8%) and in serum Ang II (by 20%) in sucrose-fed SHR compared with control. In sucrose plus vanadium-fed SHR, the lowering of the systolic blood pressure (by 11-16% of the sucrose-fed value) was accompanied by a significant decrease in Ang II levels (by 25-60% of the sucrose-fed value) and an increase in endothelin-1 level (by 61-76% of the sucrose-fed value). CONCLUSION: That Ang II levels are elevated in sucrose-induced hypertension and decreased after vanadium therapy suggests that the renin-angiotensin system plays a role in the induction of hypertension in this model. On the other hand, the elevation of endothelin-1 levels associated with a decreased systolic blood pressure might be secondary to vanadium stimulation of endothelial cells. The data suggest that endothelin-1 is not involved in sugar-induced elevations of the blood pressure.
Assuntos
Angiotensina II/sangue , Sacarose Alimentar/farmacologia , Hipertensão/sangue , Vanádio/farmacologia , Animais , Pressão Sanguínea/efeitos dos fármacos , Peso Corporal , Endotelina-1/sangue , Masculino , Radioimunoensaio , Ratos , Ratos Endogâmicos SHRRESUMO
The stress distribution in the periodontal tissue around roots of a mesially inclined mandibular second molar as the the abutment of a fixed bridge was analysed by the three dimensional photoelasticity. It was shown by 3-D photoelasticity that the stress distribution in the alveolar bone around the roots of the abutment was modified by the placement of the fixed bridge. The maximum stress points in alveolar bone around the roots of abutment were also located.
Assuntos
Dente Suporte , Análise do Estresse Dentário/métodos , Fenômenos Biomecânicos , Elasticidade , Humanos , Dente Molar , PeriodontoRESUMO
This paper introduces the composition of Castabe Glass-Ceramic (CGC), synthetic technique and physical and chemical properties. By means of TEM, SEM, XRD and EPMA techniques, the structure of CGC on K2O-MgO-Al2O-SiO2-F glass, type and size of crystallization are investigated. The results are as follows: the main crystal phase is tetrasilicic flourmica (K2Mg2.5Si4-O10F2), refractive index = 1.53, transparency = 48%, Density = 2.7 g/cm3, elastic modulus = 68.22 GPa, breaking strength = 141.1 MPa, breaking durability = 1.83 and V. H. = 505 kg/mm2. Base the above properties described, the function of CGC is similar to the Dicor (Dentsply. Int. U. S. A.) which is one of the well known material in western countries in now days.
Assuntos
Porcelana Dentária/síntese química , Materiais Biocompatíveis , Porcelana Dentária/química , Vidro , Teste de MateriaisRESUMO
The successful key of endosteal implants depends on the properties of implant materials which are very important for oral implantology at the present. Because silicon nitride has high strength and hydroxylapatite (HA) and flourapatite (FA) have good biocompatibility. In this paper, we apply silicon nitride as base material. Plasma spray HA, FA onto its surface as composite endosteal implants. Physical and chemical properties test, includes X-ray diffraction (XRD), scanning electronic microscope (SEM), EDAX and bonding strength test (push-out test). The results indicate: after plasma-spraying coating, crystalline phase of HA and FA unchanged and form a lot of pores among the crystal particles. Those pores benefit bone growing into them. It is very important for implants to be fixed in bone for long time, Ca/P ratio has no significant change. Bonding strength test results indicate: Si3N4-HA 23.6MPa, Si3N4-FA 27.12 MPa are higher than that of Ti-HA 15.07 MPa. On the basis of these studies, they are kinds of ideal implant materials.
Assuntos
Materiais Biocompatíveis , Cerâmica , Implantação Dentária Endóssea , Compostos de Silício , Apatitas , Fenômenos Químicos , Físico-Química , Durapatita , Microscopia Eletrônica de Varredura , Propriedades de Superfície , Difração de Raios XRESUMO
The interaction of endothelin-1 (ET-1), a novel vasoconstrictor peptide synthesized according to the encoded amino acid sequence, with L-NG-nitroarginine (NOARG), an L-arginine-reversible inhibitor of endothelium-derived relaxing factor (EDRF) on adrenergic receptors, was investigated. Male Sprague-Dawley rats were used in this study. Mesenteric arteries were isolated and perfused with Krebs-Ringer solution at a constant flow rate. The vasoconstrictor responses to exogenous norepinephrine were determined. Low concentrations of ET-1 (10(-11) and 10(-10) M) potentiated the pressor responses to norepinephrine without affecting the baseline perfusion pressure. Simultaneous NOARG (10(-5) M) infusion with ET-1 (10(-11) M) into the mesenteric arteries caused further enhancement of the pressor responses to exogenous norepinephrine (200 ng) without affecting the baseline perfusion pressure: 126 +/- 15% to 262 +/- 45% (p less than 0.05, vehicle control: 100%). This facilitatory effect of NOARG on the pressor response to norepinephrine was attenuated with L-arginine (10(-4) M) infusion, but not D-arginine. These results suggest that ET, one of the endothelium-derived vasoconstricting factors, interacts with EDRF to modulate the tone of resistance vessels.
Assuntos
Arginina/análogos & derivados , Endotelinas/farmacologia , Norepinefrina/farmacologia , Vasoconstrição/efeitos dos fármacos , Animais , Arginina/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Interações Medicamentosas , Técnicas In Vitro , Masculino , Artérias Mesentéricas/efeitos dos fármacos , Músculo Liso Vascular/efeitos dos fármacos , Óxido Nítrico/farmacologia , Nitroarginina , Ratos , Ratos Endogâmicos , Receptores Adrenérgicos/efeitos dos fármacosRESUMO
1. We previously reported that angiotensin II release from the mesenteric arteries of Wistar-Kyoto (WKY) and spontaneously hypertensive rats (SHR) increased in a time-dependent manner as a result of the isolation of the arteries and perfusion. This phenomenon appeared to be due to the withdrawal of circulating angiotensin II (AII). 2. The purpose of the present study was to test the hypothesis that vascular AII generation may be negatively regulated by circulating AII in WKY and SHR, and to clarify the role of this vascular angiotensin II in the sustained hypertension of SHR following nephrectomy. 3. The mesenteric arteries from kidney-intact and nephrectomized WKY and SHR were perfused and the amount of AII released into the perfusate was measured. The effects of the angiotensin converting enzyme inhibitor, captopril, and the effects of supplementation of renal renin and circulating angiotensins to nephrectomized rats, by blood exchange between kidney-intact and nephrectomized rats, on AII release were examined to clarify the pathway of vascular AII generation after nephrectomy. 4. Nephrectomy caused augmentation of vascular AII release both in WKY and SHR in spite of the abolishment of circulating renin. Captopril reduced this enhanced release of AII, but blood exchange did not affect it. There was no significant difference in these responses between WKY and SHR. 5. These results suggest that WKY and SHR have in common a potent pathway for production of vascular AII in response to the withdrawal of circulating AII, although this pathway is not responsible for the sustained hypertension of SHR after nephrectomy. The precise pathophysiological role of this pathway remains to be elucidated.
Assuntos
Angiotensina II/fisiologia , Hipertensão/fisiopatologia , Artérias Mesentéricas/fisiologia , Sistema Renina-Angiotensina/fisiologia , Angiotensina II/metabolismo , Animais , Técnicas In Vitro , Rim/fisiologia , Masculino , Artérias Mesentéricas/metabolismo , Nefrectomia , Radioimunoensaio , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Renina/fisiologiaRESUMO
The objectives of the present study were to test the hypothesis that vascular angiotensin II (AII) generation may be negatively regulated by circulating AII in Wistar-Kyoto rats (WKY) and spontaneously hypertensive rats (SHR), and to clarify the role of this vascular AII in the sustained hypertension seen in SHR following nephrectomy. The mesenteric arteries from kidney-intact and nephrectomised WKY and SHR were perfused, and the level of AII released into the perfusate were measured. The effects of CV-11974, a newly developed nonpeptide AII receptor antagonist, on AII release were examined to investigate the existence of a local feedback system in the blood vessels. Nephrectomy augmented vascular AII release both in WKY and SHR despite the reduction in circulating AII. CV-11974 significantly increased AII release from the mesenteric arteries of kidney-intact rats. There were no significant differences in these responses between WKY and SHR. These results suggest that WKY and SHR share a potent pathway for producing vascular AII in response to the withdrawal of circulating AII, although this pathway is not responsible for the sustained hypertension seen in SHR after nephrectomy.
Assuntos
Angiotensina II/biossíntese , Rim/fisiologia , Artérias Mesentéricas/fisiologia , Angiotensina II/sangue , Angiotensina II/metabolismo , Animais , Benzimidazóis/farmacologia , Compostos de Bifenilo , Retroalimentação/fisiologia , Hipertensão/metabolismo , Hipertensão/fisiopatologia , Rim/cirurgia , Masculino , Artérias Mesentéricas/metabolismo , Nefrectomia , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Renina/sangue , Tetrazóis/farmacologiaRESUMO
We investigated the release of endothelin-1 (ET) from rat mesenteric arteries to clarify its pathophysiological role in the sustained hypertension of spontaneously hypertensive rats (SHR) following nephrectomy and the regulatory mechanism of the ET release which might be modified by vascular angiotensins and bradykinins. Nephrectomy increased the plasma level of ET and enhanced the ET release in both SHR and Wistar-Kyoto rats (WKY). CV-11974, an angiotensin II receptor antagonist, did not affect the ET release from arteries of nephrectomized rats. On the contrary, infusion of captopril, a converting enzyme inhibitor, further enhanced the ET release in both intact and nephrectomized rats. These findings suggest that the release of ET from mesenteric arteries may be regulated by bradykinins, but not by angiotensins. This pressor substance does not contribute to the sustained hypertension because the enhanced production of ET observed in both SHR and WKY. However, there is a possibility that the exaggerated responsiveness of vascular ET may in part account for local vascular tone and vascular remodeling in renal dysfunction.
Assuntos
Captopril/farmacologia , Endotelinas/metabolismo , Artérias Mesentéricas/metabolismo , Nefrectomia , Análise de Variância , Antagonistas de Receptores de Angiotensina , Animais , Benzimidazóis/farmacologia , Compostos de Bifenilo , Endotelinas/sangue , Masculino , Artérias Mesentéricas/efeitos dos fármacos , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Peptidil Dipeptidase A/metabolismo , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Tetrazóis/farmacologiaRESUMO
Two separate studies were performed on hypertensive rats to assess the effects of wild, uncultivated garlic on elevated systolic blood pressure (SBP) and other cardiovascular parameters. Also, effects of wild garlic and cultivated garlic preparations were compared and the mechanisms behind pressure-lowering abilities of different garlic preparations were examined. The initial study determined that wild garlic lowers blood pressure. In the second study, cardiovascular effects of three different concentrations of wild garlic and two different cultivated garlics, i.e., a preparation low in allicin and one high in allicin, were compared. All three garlic preparations decreased SBP significantly. Wild garlic produced the greatest pressure-lowering effects, and the least pressure-lowering effects were seen with low-allicin garlic. Compared with control rats, circulating angiotensin II levels were significantly lower in all garlic-eating rats. Losartan decreased blood pressure significantly less and Nw-nitro-L arginine-methyl ester hydrochloride (LNAME) increased blood pressure significantly more in garlic-eating rats than in control rats, suggesting that the renin-angiotensin system (RAS) was less active and the nitric oxide system more active in garlic-consuming hypertensive rats. Accordingly, different garlic preparations, especially wild garlic, favorably influenced high SBP in hypertensive rats. These results suggest that both the RAS and the nitric oxide system are involved in the antihypertensive effects of garlic in hypertensive rats.