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1.
Nat Prod Res ; 35(4): 676-680, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30931614

RESUMEN

This study aimed to evaluate the cytotoxicity and genotoxicity from Inga laurina leaves extracts and fractions and obtain their chemical profile. The chemical profile of the crude extract from I. laurina leaves and its fractions was investigated through 1H NMR, RP-HPLC-PDA by co-injection with authentic standards and HPLC-MS. The quinone reductase induction as a biomarker for cancer chemoprevention was evaluated in murine hepatocellular carcinoma line, whereas the cytotoxicity was evaluated by sulforhodamine B assay (SRB) using HepG2 cell line and genotoxicity was evaluated by comet assay. The phytochemical analysis of the leaves crude extract and its fractions showed the presence of 2-hydroxyethyl-dodecanoate and the phenolic compounds: gallic acid, methyl gallate, p-coumaric acid, cinnamic acid, myricetin-3-O-(2″-O-galoyl)-α-rhamnopyranoside, proanthocyanidin A-2 and myricetrin. All the fractions tested were not considered cytotoxic against the selected human cancer cell lines, they did not cause genotoxic in some concentrations damage and induced the enzyme quinone reductase.


Asunto(s)
Fabaceae/química , Mutágenos/toxicidad , Animales , Muerte Celular/efectos de los fármacos , Cromatografía Líquida de Alta Presión , Ensayo Cometa , Daño del ADN , Inducción Enzimática/efectos de los fármacos , Células Hep G2 , Humanos , Ratones , NAD(P)H Deshidrogenasa (Quinona)/biosíntesis , Fitoquímicos/análisis , Fitoquímicos/farmacología , Extractos Vegetales/química , Hojas de la Planta/química
2.
Sci Rep ; 10(1): 13824, 2020 08 14.
Artículo en Inglés | MEDLINE | ID: mdl-32796880

RESUMEN

The present work assessed the effects of dietary ratios of essential fatty acids, arachidonic (ARA), eicosapentaenoic (EPA) and docosahexaenoic acid (DHA), on liver and intestine oxidative status, intestinal histomorphology and gut microbiota of gilthead sea bream. Four isoproteic and isolipidic plant-based diets were formulated containing a vegetable oil blend as the main lipid source. Diets were supplemented with ARA/EPA/DHA levels (%DM) equivalent to: 2%:0.2%:0.1% (Diet A); 1.0%:0.4%:0.4% (Diet B); 0%:0.6%:0.6% (Diet C); 0%:0.3%:1.5% (Diet D) and tested in triplicate groups for 56 days. Lipid peroxidation was higher in fish fed diets C and D while no differences were reported between diets regarding total, oxidized, and reduced glutathione, and oxidative stress index. Glutathione reductase was higher in fish fed diet A than diets C and D. No histological alterations were observed in the distal intestine. Lower microbiota diversity was observed in intestinal mucosa of fish fed diet C than A, while diets C and D enabled the proliferation of health-promoting bacteria from Bacteroidetes phylum (Asinibacterium sp.) and the absence of pathogenic species like Edwardsiella tarda. Overall, results suggest that a balance between dietary ARA/EPA + DHA promotes gilthead sea bream juveniles' health however higher dietary content of n-3 LC-PUFA might limited the presence of microbial pathogens in intestinal mucosa.


Asunto(s)
Alimentación Animal , Fenómenos Fisiológicos Nutricionales de los Animales/fisiología , Ácido Araquidónico/administración & dosificación , Dieta/veterinaria , Suplementos Dietéticos , Ácidos Docosahexaenoicos/administración & dosificación , Ácido Eicosapentaenoico/administración & dosificación , Microbioma Gastrointestinal , Estrés Oxidativo , Dorada/metabolismo , Dorada/microbiología , Animales , Glutatión Reductasa/metabolismo , Mucosa Intestinal , Intestinos/microbiología , Peroxidación de Lípido , Hígado/metabolismo
3.
Fish Physiol Biochem ; 42(6): 1699-1707, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27325349

RESUMEN

Lipoic acid (LA) is an antioxidant that also favors glucose uptake in mammals. Until now, there are no studies evaluating the potential effect of this molecule on glycemic control in fish. It was evaluated LA effects on glucose uptake in common carp Cyprinus carpio fed with carbohydrate diets from two carbohydrate sources: glucose (GLU) and starch (STA), and supplemented or not with LA, being the diets: +GLU/-LA (GLU); +GLU/+LA (GLU + LA); +STA/-LA (STA); and +STA/+LA (STA + LA). Carp juveniles (6.5 ± 0.1 g) were fed with each diet ad libitum 4 times a day, during 68 days. Muscle glycogen concentration was higher (p < 0.05) in GLU and GLU + LA than in STA and STA + LA groups. On fish fed with starch, muscle cholesterol and triglyceride concentrations were higher (p < 0.05) in fish fed diets supplemented with LA. Muscle protein levels were higher in fish fed with LA, independent of the diet carbohydrate source. Lipid peroxidation was significantly reduced (p < 0.05) in fish muscle on fish fed the STA + LA diets when compared with the STA diet. Our findings indicate that LA modulates lipid, proteins and carbohydrate metabolism together with the well-known antioxidant effect. Also, LA showed to enhance starch utilization taking into account muscle cholesterol and triglyceride levels.


Asunto(s)
Antioxidantes/farmacología , Carpas/crecimiento & desarrollo , Carpas/metabolismo , Carbohidratos de la Dieta/farmacología , Ácido Tióctico/farmacología , Animales , Acuicultura/métodos , Colesterol/metabolismo , Dieta , Glucosa/metabolismo , Hemoglobina Glucada/análisis , Glucógeno/metabolismo , Hematócrito , Peroxidación de Lípido , Músculos/efectos de los fármacos , Músculos/metabolismo , Sustancias Reactivas al Ácido Tiobarbitúrico/metabolismo , Triglicéridos/metabolismo
4.
J Anim Physiol Anim Nutr (Berl) ; 100(3): 590-600, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26614118

RESUMEN

The aim of this study was to evaluate the effect of protein reduction and supplementation of l-glutamic acid in male broiler diets. A total of 648 chicks of the Cobb 500 strain were distributed in a completely randomized design with six treatments and six replications with eighteen birds per experimental unit. The study comprised pre-starter (1-7 days), starter (8-21 days), growth (22-35 days) and final (36-45 days) phases. The first treatment consisted of a control diet formulated according to the requirements of essential amino acids for each rearing phase. The second and third treatments had crude protein (CP) reduced by 1.8 and 3.6 percentage points (pp) in relation to the control diet respectively. In the fourth treatment, l-glutamic acid was added to provide the same glutamate level as the control diet, and in the last two treatments, the broilers were supplemented with 1 and 2 pp of glutamate above that of the control diet respectively. The reduction in CP decreased the performance of broilers and the supplementation of l-glutamic acid did not influence performance when supplied in the diets with excess of glutamate. The lowest excreted nitrogen values were observed in the control diet, and treatments 2 and 3, respectively, in comparison with treatments with the use of l-glutamic acid (5 and 6). Retention efficiency of nitrogen was better in the control diet and in the treatment with a reduction of 1.8 pp of CP. It was verified that the serum uric acid level decreased with the CP reduction. A reduction in CP levels of up to 21.3%, 18.8%, 18.32% and 17.57% is recommended in phases from 1 to 7, 8 to 21, 22 to 35 and at 36 to 42 days, respectively, with a level of glutamate at 5.32%, 4.73%, 4.57%, 4.38%, also in these phases.


Asunto(s)
Alimentación Animal/análisis , Pollos/crecimiento & desarrollo , Dieta/veterinaria , Proteínas en la Dieta/farmacología , Ácido Glutámico/farmacología , Nitrógeno/metabolismo , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Proteínas en la Dieta/administración & dosificación , Ácido Glutámico/administración & dosificación , Masculino
5.
Nutr Metab Cardiovasc Dis ; 24(6): 606-13, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24602606

RESUMEN

BACKGROUND & AIMS: Butyrate is a four-carbon fatty acid that presents anti-inflammatory, anti-oxidative and apoptotic properties in colon and several cell lines. Because atherosclerosis has important oxidative and inflammatory components, butyrate could reduce oxidation and inflammation, impairing atherogenesis. We evaluated the effects of butyrate supplementation of butyrate on atherosclerosis and its mechanisms of action. METHODS AND RESULTS: ApoE knockout mice were fed on chow diet or 1% butyrate-supplemented chow diet (Butyrate) for 10 weeks to assess atherosclerosis lesions area and inflammatory status. Macrophage and endothelial cells were also pretreated with butyrate (0.5 mM) for 2 h before oxLDL stimulation to study oxLDL uptake and pro and anti-inflammatory cytokine production. Butyrate reduced atherosclerosis in the aorta by 50%. In the aortic valve, butyrate reduced CCL2, VCAM1 and MMP2 productions in the lesion site, resulting in a lower migration of macrophage and increased collagen depositions in the lesion and plaque stability. When EA.hy926 cells were pretreated with butyrate, oxLDL uptake, CD36, VCAM1, CCL2 TNF, IL1ß and IL6 productions were reduced, whereas IL10 production was increased. These effects were accompanied by a lower activation of NFκB due to a lower nuclear translocation of the p65 subunit. CONCLUSION: Oral butyrate is able to slow the progression of atherosclerosis by reducing adhesion and migration of macrophages and increasing plaque stability. These actions are linked to the reduction of CD36 in macrophages and endothelial cells, decreased pro-inflammatory cytokines and lower activation of NFκB all of these data support a possible role for butyrate as an atheroprotective agent.


Asunto(s)
Antiinflamatorios no Esteroideos/uso terapéutico , Antioxidantes/uso terapéutico , Aterosclerosis/dietoterapia , Ácido Butírico/uso terapéutico , Suplementos Dietéticos , Placa Aterosclerótica/prevención & control , Factor de Transcripción ReIA/antagonistas & inhibidores , Animales , Antiinflamatorios no Esteroideos/metabolismo , Antioxidantes/metabolismo , Aorta/inmunología , Aorta/metabolismo , Aorta/patología , Válvula Aórtica/inmunología , Válvula Aórtica/metabolismo , Válvula Aórtica/patología , Aterosclerosis/inmunología , Aterosclerosis/metabolismo , Aterosclerosis/fisiopatología , Ácido Butírico/metabolismo , Antígenos CD36/antagonistas & inhibidores , Antígenos CD36/metabolismo , Adhesión Celular , Línea Celular , Movimiento Celular , Núcleo Celular , Células Cultivadas , Endotelio Vascular/inmunología , Endotelio Vascular/metabolismo , Endotelio Vascular/patología , Humanos , Macrófagos Peritoneales/inmunología , Macrófagos Peritoneales/metabolismo , Macrófagos Peritoneales/patología , Masculino , Ratones Noqueados , Placa Aterosclerótica/etiología , Transporte de Proteínas , Factor de Transcripción ReIA/metabolismo
6.
Heredity (Edinb) ; 101(4): 351-8, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18594559

RESUMEN

In flowering plants, self-incompatibility is a genetic mechanism that prevents self-fertilization. In gametophytic self-incompatibility (GSI), pollen specificity is encoded by the haploid genotype of the pollen tube. In GSI, specificities are maintained by frequency-dependent selection, and for diploid species, at equilibrium, equal specificity frequencies (isoplethy) are expected. This prediction has been tested in diploid, but never in polyploid self-incompatible species. For the latter, there is no theoretical expectation regarding isoplethy. Here, we report the first empirical study on specificity frequencies in a natural population of a polyploid self-incompatible species, Prunus spinosa. A total of 32 SFB (the pollen S gene) putative specificities are observed in a large sample from a natural population. Although P. spinosa is polyploid, the number of specificities found is similar to that reported for other diploid Rosaceae species. Unequal specificity frequencies are observed.


Asunto(s)
Proteínas de Plantas/genética , Polen/genética , Poliploidía , Prunus/genética , Alelos , Frecuencia de los Genes , Genética de Población , Datos de Secuencia Molecular , Filogenia , Prunus/clasificación , Selección Genética , Análisis de Secuencia de ADN
7.
Transplant Proc ; 38(6): 1796-9, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16908284

RESUMEN

INTRODUCTION: The aim of this work was to study the effects of hyperbaric oxygenation as a preservation technique for small bowel transplantation. METHODS: Twenty 2-month-old male Wistar rats weighting 250 g were divided into two groups: group A (n = 10) in which the small bowel was preserved for 12 hours, and group B (n = 10) in which the small bowel was preserved for 24 hours. After vascular and intraluminal perfusion, 3-cm segments were maintained in Ringer's solution at temperatures between 2 degrees C to 4 degrees C and in normobaric O2 conditions (groups A1, B1) or conditioned in an hyperbaric O2 metal chamber (100% oxygen at 5.5 absolute atmospheres) (groups A2, B2). After this preservation time, we studied intestinal tissue injury and morphometric analysis of the villi. RESULTS: Mucosal injury was significantly greater among group A1 compared to group A2 animals. The grade of the lesions was greater among group B1 compared to group B2 animals. Group A1 showed no difference from Group B1. For lesion grade, the range was smaller in group A2 and group B2 animals. The villi height was significantly smaller in groups A1 and B1 compared to the other groups; whereas it was higher in group A2 as compared with B2. CONCLUSION: Hyperbaric oxygenation may play a role as a preservation technique. Further research is necessary.


Asunto(s)
Oxigenoterapia Hiperbárica/métodos , Yeyuno , Preservación de Órganos/métodos , Animales , Oxigenoterapia Hiperbárica/instrumentación , Mucosa Intestinal/patología , Yeyuno/patología , Masculino , Microvellosidades/patología , Modelos Animales , Ratas , Ratas Wistar
8.
Transplant Proc ; 38(6): 1876-8, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16908311

RESUMEN

UNLABELLED: This study was conducted to assess apoptosis and nuclear proliferation in rat small bowel submitted to hypothermic hyperbaric oxygenation for preservation. METHODS: Twenty two-month-old, male Wistar rats, weighing 250 g were divided into two groups: group I (n = 10), in which the small bowel was preserved for 12 hours, and group II (n = 10) in which the small bowel was preserved for 24 hours. After vascular and intraluminal perfusion, 3-cm segments were maintained in Ringer's solution at 2 degrees to 4 degrees C under normobaric conditions (groups Ia and IIa) or conditioned in a small hyperbaric metal chamber with 100% oxygen at 5.5 absolute atmospheres (groups Ib and IIb). After 12 or 24 hours, apoptotic and mitotic indices were evaluated by immunohistochemical methods. RESULTS: The apoptotic index was significantly higher in small bowel segments in groups Ia and IIa compared with groups Ib and IIb. The mitotic index was significantly higher among group IIb. CONCLUSION: Hypothermic hyperbaric oxygenation reduced intestinal epithelial apoptosis and increased nuclear proliferation during rat small bowel preservation.


Asunto(s)
Apoptosis , Núcleo Celular/fisiología , Núcleo Celular/ultraestructura , Intestino Delgado/citología , Intestino Delgado/fisiología , Preservación de Órganos/métodos , Animales , División Celular , Oxigenoterapia Hiperbárica , Hipotermia Inducida , Mucosa Intestinal/citología , Mucosa Intestinal/fisiología , Masculino , Índice Mitótico , Modelos Animales , Ratas , Ratas Wistar
9.
Transplant Proc ; 38(6): 1879-82, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16908312

RESUMEN

UNLABELLED: This study was designed to investigate the feasibility of building a simple and inexpensive device to preserve organs or tissues in hyperbaric and hypothermic conditions. METHODS: The device was built on a 40-cm wide, 28-cm long, and 23-cm deep stainless steel chassis. The pressure vessel was built by a 7.8-cm bore stainless steel cylinder put inside another 12-cm cylinder welded together and closed by a steel plate on the top and bottom. The inferior plate was welded, and the superior one was fixed by manual clasp nut. The cooling system is made up of air compressor, condenser, expansion area, and cooling worm that is located between the cylinders. The temperature-controlling device is a computer processor contained in an integrated-circuit chip, with a on-off system to maintain the chamber temperature between 2 degrees to 4 degrees C. The compression of the chamber is performed by lateral coupling with the oxygen cylinder and is maintained at 5.5 absolute atmospheres and controlled by air pressure gauge. The maximal work pressure was evaluated by spreadsheet. Temperature or pressure changes were evaluated by 12- and 24-hour assays. RESULTS: The maximal work pressure permitted was 6.5 absolute atmospheres. Thus, the container was free from danger. The temperature inside the chamber was kept between 2 degrees and 4 degrees C. The production costs of the prototype was US$1000. DISCUSSION: The manufacture of the refrigerating hyperbaric chamber is viable, simple, and inexpensive.


Asunto(s)
Oxigenoterapia Hiperbárica/métodos , Preservación de Órganos/métodos , Frío , Diseño de Equipo , Oxigenoterapia Hiperbárica/instrumentación , Preservación de Órganos/instrumentación , Refrigeración , Temperatura
10.
Brain Res ; 1038(1): 32-40, 2005 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-15748870

RESUMEN

The Wistar Audiogenic Rat (WAR) is a genetic model of reflex epilepsy with seizures induced by high-intensity sound stimulation (120 dB SPL). In spite of the known neural substrates involved in WAR seizure phenotype, neuroendocrine hypothalamic neurons were never investigated. In this work, AVP immunohistochemistry in the hypothalamus and radioimmunoassay (RIA) in plasma and in hypothalamic and hypophysial tissues were performed on both controls and WARs in order to evaluate the dynamics of AVP release due to seizure induction. Susceptible animals (WARs) displayed at least tonic-clonic convulsions followed by clonic spasms, while resistant Wistar rats (R) had no convulsive behavior. Animals were sacrificed at 3 instances: basal condition (without stimulus) and at 3 and 10 min after sound stimulation. For the immunohistochemistry AVP study, brains were harvested and processed by the avidin-biotin-peroxidase detection method. Optic densitometry was used for quantifying AVP labeling in supraoptic (SON) and paraventricular (PVN) hypothalamic nuclei. SON presented higher densitometry levels (%D--relative to background) for both WARs and R when compared to PVN. Nevertheless, both nuclei presented a marked decrease, referenced to basal levels, in %D for WARs at 3 min (approximately 35%) against a discrete change for R (approximately 90%). RIA results were significantly higher in the hypophysis of WARs when compared to R rats, at 3 min. Also, at 3 min, plasma AVP in WARs (89.32 +/- 24.81 pg/mL) were higher than in R (12.01 +/- 2.39 pg/mL). We conclude, based on the AVP releasing profiles, that vasopressinergic hypothalamic neurons are recruited during the audiogenic seizure of WARs.


Asunto(s)
Epilepsia Refleja/fisiopatología , Retroalimentación Fisiológica , Hipotálamo/metabolismo , Neuronas/metabolismo , Vasopresinas/metabolismo , Estimulación Acústica , Animales , Modelos Animales de Enfermedad , Hipotálamo/química , Hipotálamo/citología , Masculino , Hipófisis/química , Ratas , Ratas Wistar , Vasopresinas/análisis , Vasopresinas/sangre
11.
Braz J Med Biol Res ; 31(3): 421-30, 1998 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9698793

RESUMEN

In the present study, using noise-free stimulated signals, we performed a comparative examination of several preprocessing techniques that are used to transform the cardiac event series in a regularly sampled time series, appropriate for spectral analysis of heart rhythm variability (HRV). First, a group of noise-free simulated point event series, which represents a time series of heartbeats, was generated by an integral pulse frequency modulation models. In order to evaluate the performance of the preprocessing methods, the differences between the spectra of the preprocessed simulated signals and the true spectrum (spectrum of the model input modulating signals) were surveyed by visual analysis and by contrasting merit indices. It is desired that estimated spectra match the true spectrum as close as possible, showing a minimum of harmonic components and other artifacts. The merit indices proposed to quantify these mismatches were the leakage rate, defined as a measure of leakage components (located outside some narrow windows centered at frequencies of model input modulating signals) with respect to the whole spectral components, and the numbers of leakage components with amplitudes greater than 1%, 5% and 10% of the total spectral components. Our data, obtained from a noise-free simulation, indicate that the utilization of heart rate values instead of heart period values in the derivation of signals representative of heart rhythm results in more accurate spectra. Furthermore, our data support the efficiency of the widely used preprocessing technique based on the convolution of inverse interval function values with a rectangular window, and suggest the preprocessing technique based on a cubic polynomial interpolation of inverse interval function values and succeeding spectral analysis as another efficient and fast method for the analysis of HRV signals.


Asunto(s)
Pruebas de Función Cardíaca/métodos , Frecuencia Cardíaca/fisiología , Procesamiento de Señales Asistido por Computador , Estimulación Acústica , Análisis Espectral
12.
Braz. j. med. biol. res ; 31(3): 421-30, Mar. 1998. tab, graf
Artículo en Inglés | LILACS | ID: lil-212279

RESUMEN

In the present study, using noise-free simulated signals, we performed a comparative examination of several preprocessing techniques that are used to transform the cardiac event series in a regularly sampled time series, appropriate for spectral analysis of heart rhythm variability (HRV). First, a group of noise-free simulated point event series, which represents a time series of heartbeats, was generated by an integral pulse frequency modulation model. In order to evaluate the performance of the preprocessing methods, the differences between the spectra of the preprocessed simulated signals and the true spectrum (spectrum of the model input modulating signals) were surveyed by visual analysis and by contrasting merit indices. It is desired that estimated spectra match the true spectrum as close as possible, showing a minimum of harmonic components and other artifacts. The merit indices proposed to quantify these mismatches were the leakage rate, defined as a measure of leakage components (located outside some narrow windows centered at frequencies of model input modulating signals) with respect to the whole spectral components, and the numbers of leakage components with amplitudes greater than 1 percent, 5 percent and 10 percent of the total spectral components. Our data, obtained from a noise-free simulation, indicate that the utilization of heart rate values instead of heart period values in the derivation of signals representative of heart rhythm results in more accurate spectra. Furthermore, our data support the efficiency of the widely used preprocessing technique based on the convolution of inverse interval function values with a rectangular window, and suggest the preprocessing technique based on a cubic polynomial interpolation of inverse interval function values and succeeding spectral analysis as another efficient and fast method for the analysis of HRV signals.


Asunto(s)
Pruebas de Función Cardíaca/métodos , Frecuencia Cardíaca , Procesamiento de Señales Asistido por Computador , Estimulación Acústica , Análisis Espectral
13.
Hypertension ; 19(2 Suppl): II56-61, 1992 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-1310484

RESUMEN

The heptapeptide angiotensin-(1-7) is a circulating biologically active product of the renin-angiotensin system. In this study, we evaluated the role of the vascular endothelium in the formation of angiotensin-(1-7). Metabolism of 125I-angiotensin I was investigated using confluent cultured bovine and human aortic and umbilical vein endothelial cells. The fetal calf serum-supplemented medium was replaced by serum-free medium containing 0.2% bovine serum albumin. One hour later, this medium was replaced by serum-free medium containing 125I-angiotensin I. After incubation of 125I-angiotensin I for various intervals at 37 degrees C, the medium was collected and analyzed for formed products by high-performance liquid chromatography. Products of angiotensin I metabolism were identified by comparison of their retention times with those of radiolabeled standards. The contribution of proteases released into the medium was evaluated by incubation of 125I-angiotensin I with medium previously incubated for 1 hour with endothelial cells. Incubation of 125I-angiotensin I with bovine and human endothelial cells produced a time-dependent generation of 125I-angiotensin-(1-7) greater than 125I-angiotensin II greater than 125I-angiotensin-(1-4). Generation of angiotensin peptides was not due to the presence of proteases in the medium. When human umbilical endothelial cells were incubated in the presence of the angiotensin converting enzyme inhibitor enalaprilat (1 microM), generation of angiotensin II was undetectable. In contrast, angiotensin-(1-7) production increased by an average of 30%.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Angiotensina II/biosíntesis , Endotelio Vascular/metabolismo , Fragmentos de Péptidos/biosíntesis , Angiotensina I/metabolismo , Angiotensina I/farmacología , Animales , Enalaprilato/farmacología , Humanos , Radioisótopos de Yodo , Peptidil-Dipeptidasa A/metabolismo , Inhibidores de Proteasas/farmacología , Venas Umbilicales/metabolismo
14.
J Hypertens ; 9(7): 631-8, 1991 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-1653799

RESUMEN

In order to understand angiotensin metabolism in the canine brain, we determined the molecular forms of angiotensin peptides present in the hypothalamus of the dog and carried out measurements of the metabolism of 125I-angiotensin I in homogenates of that tissue. Angiotensin peptides were extracted from canine hypothalamic tissue and quantified by specific radioimmunoassays combined with high-performance liquid chromatography. The major angiotensin peptides detected were angiotensin-(2-7) (391.2 +/- 16.8 pg/g tissue) and angiotensin-(3-7) (864.8 +/- 128.1 pg/g). Angiotensin II immunoreactivity was mainly composed of angiotensin-(3-8) (117.5 +/- 64 pg/g) and trace amounts of angiotensin II and angiotensin III. Angiotensin I immunoreactivity was composed of angiotensin I (52.3 +/- 5.8 pg/g). In separate experiments, addition of 125I-angiotensin I into supernatants (18,000 g for 2 min) of canine hypothalamic homogenates resulted in the accumulation of 125I-angiotensin-(1-7) as the major peptide product (14% of the total 125I-radioactivity) at 2 min. Incubation of the homogenate supernatants with enalaprilat (1 mumol/l), phosphoramidon (10 mumol/l), or ethylenediamine tetraacetic acid (1 mmol/l) did not inhibit the production of 125I-angiotensin-(1-7). In contrast, addition of Z-Pro-Prolinal (1 mumol/l), a specific inhibitor of prolyl endopeptidase, prevented the generation of 125I-angiotensin-(1-7) from 125I-angiotensin I by 47.0 +/- 8.0% (n = 6).(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Angiotensina II/metabolismo , Endopeptidasas/metabolismo , Hipotálamo/metabolismo , Serina Endopeptidasas , Angiotensina I/metabolismo , Animales , Cromatografía Líquida de Alta Presión , Perros , Técnicas In Vitro , Radioisótopos de Yodo , Masculino , Fragmentos de Péptidos/metabolismo , Prolil Oligopeptidasas , Radioinmunoensayo , Sistema Renina-Angiotensina/fisiología
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