The osmotic fragility (OF) test is used to determine the extent of red blood cell hemolysis (RBCH) produced by osmotic stress. RBCH is dependent upon cell volume, surface area, and functional integrity of cell membranes. The variation of cell lysis with stress reflects underlying cell subpopulations and their membranes' cytoskeletal functionality. OF was determined on blood from New Zealand white rabbits. The dependence of RBCH on NaCl concentration ([NaCl]) was determined spectrophotometrically by measuring absorbance (Abs) from hemoglobin release at 545 nm. Abs data were fitted to the equation Abs = p3 erfc( ([NaCl] - p1) p2) where p3 reflects maximum RBCH, p1 measures the [NaCl] at 50% RBCH, and p2 shows the dispersion in [NaCl] producing the RBCH. Parameter values for control blood were p1 = 0.4489 ± 0.0016; p2 = 0.0486 ± 0.0016; and p3 = 0.4366 ± 0.0022. Addition of indomethacin (9.6 μg/mL) produced an increased fragility in the RBC's characterized by increased values of p1 and p2. Normalization of the data to p3 did not change the values of p1 or p2. Our equation satisfactorily describes the variation in RBCH as a function of [NaCl]. The parameters of the equation can be used to quantitatively characterize Abs/[NaCl]. The compare pharmacological, Toxicological, and pathological effects on the OF of RBC's.

The hypothesis that calcium influxes from the extracellular space play an important role in the pathogenesis of irreversible anoxic injury was tested using isolated adult rat myocytes. Myocytes treated with 6 mm amytal and 3 mm iodoacetate and subsequently incubated in either calcium-containing (1.12 mm) or calcium-free media (with or without 1 mm EGTA) developed rigor contracture (cell squaring) and cell death (trypan blue permeability) at the same rate. The rates of cell death in both calcium-containing and calcium-free media were increased by incubation in hypotonic media even though the rates of contracture development remained unaltered. Cells developed osmotic fragility prior to membrane permeability increases. The calcium ionophore, A23187 (10 μm), induced rapid rounding of rod-shaped cells subjected only to mitochondrial inhibition in calcium containing media, confirming its ability to cause an increase in cellular permeability to calcium. However, A23187 did not alter the rates of cell death of totally metabolically inhibited myocytes in either calcium-containing or calcium-free media with EGTA. The results indicate that influxes of calcium are not necessary for the development of irreversible injury in metabolically inhibited, isolated myocytes.

Isolated adult rat myocytes were subjected to 180 min of metabolic inhibition or incubated in ischaemic pellets, in the presence and absence of 10 μm okadaic acid (OA) or calyculin A (CL-A). Contracture and viability was determined by light microscopic analysis of trypan blue-stained preparations and ATP levels by HPLC. Osmotic fragility was assessed by brief hypotonic swelling of cells in 170 or 85 mOsm media prior to determination of viability. Neither drug significantly affected the relatively rapid rates of contracture of myocytes during metabolic inhibition, and both afforded significant protection from development of trypan blue permeability and osmotic fragility. Both OA and CL-A significantly accelerated the rates of contracture and ATP depletion of myocytes during ischaemic incubations. Despite an enhanced rate of ATP depletion, which would be expected to accelerate development of injury, neither drug accelerated development of loss of viability or development of osmotic fragility as measured by 170 mOsm swelling. Mathematical compensation for different rates of ATP depletion confirmed that a protective effect of the drugs, during ischaemic incubation, was masked by their enhancement of the rate of injury, following swelling at 170 mOsm. When the effects of CL-A on ischaemic cells were examined at 85 mOsm, a more stringent test for osmotic fragility, protection was found without compensation for differing rates of ATP depletion. A dose/response curve for CL-A showed some effect at 100 nm and a nearly full effect during metabolic inhibition at 1 μm concentrations. It is concluded that protein phosphatase inhibitors reduce the rates of development of osmotic fragility of metabolically inhibited cells and reduces the rate of injury relative to the rate of ATP depletion of ischaemic cardiomyocytes. Phosphorylation mechanisms may be important to development of irreversible myocardial cell injury.

The relationship between myocardial cell contracture and injury during total metabolic inhibition (amylobarbital and iodacetic acid) and ischemia was examined, using 5-50 mm butanedione monoxime (BDM) as an inhibitor of contracture. BDM had no apparent effect on control myocytes during 180 min incubations, but inhibited contracture following anoxia or ischemia in a dose-dependent fashion, as directly quantitated by length/width ratios. Cellular ATP levels decreased at a similar rate in the absence or presence of BDM, following metabolic inhibition. BDM-mediated inhibition of contracture was associated with accelerated cell injury, as defined by: the uptake of an extracellular marker (trypan blue) by the cardiomyocytes, by direct analysis of myoglobin released into the supernatant and by ultrastructural demonstration of defects in sarcolemmal membrane integrity. Calcium was not required for BDM's enhancement of injury, in that cells incubated in calcium free-EGTA buffer showed a similar BDM-mediated acceleration of injury. In the presence or absence of calcium, enhancement of injury was more marked in cells osmotically stressed with a brief incubation in hypotonic buffer, than in cells resuspended in isotonic media. It is concluded that BDM enhances development of osmotic fragility of inhibited or ischemic cardiomyocytes and that contracture is not a necessary contributing factor to myocardial cell death.

Submitted by Claudia Rocha (claudia.rocha@udesc.br) on 2018-03-16T13:58:06Z No. of bitstreams: 1 PGCA17MA220.pdf: 918895 bytes, checksum: 7bd16289da82c230fdc69d3a30554771 (MD5) / Made available in DSpace on 2018-03-16T13:58:06Z (GMT). No. of bitstreams: 1 PGCA17MA220.pdf: 918895 bytes, checksum: 7bd16289da82c230fdc69d3a30554771 (MD5) Previous issue date: 2017-02-20 / Capes / Promop / Laboratory tests in veterinary medicine are of particular importance with regard to the establishment of an efficient diagnosis. In the practice of the equine clinic a veterinary clinical pathology facilitates an interpretation of disturbances that damages the fetus and a pregnant female. In the pregnancy period, there is greater oxygen consumption and consequent changes in energy consumption and greater exposure to oxidative stress, which may cause embryonic reabsorption and abortions. The objective of this research was to evaluate the main hematological and biochemical alterations of the oxidative metabolism in Crioula mares in the gestation period. Blood samples were collected from 44 mares arranged in four different gestational groups, with eleven mares in each group (G0 = empty mares, G3 = 3 months gestation, G6 = 6 months gestation and G10 = 10 months gestation). The gestation of these animals was confirmed by means of sonographic examinations and palpation. The mares were evaluated by physical examination, blood count and biochemical evaluation. The samples were collected in mares from the same property, submitted to the same nutritional and sanitary management. The hemogram and clinical biochemistry were evaluated, in which was dosed urea, creatinine, total serum protein (PST), albumin, globulins, alkaline phosphatase (AF), gamma glutamyltransferase (GGT), alanine aminotransferase (ALT), aspartate aminotransferase (AST), Creatine kinase (CK), calcium, phosphorus, magnesium, total, diretct and indirect bilirubin, lactate, cholesterol, triglycerides, glucose, and iron dosage. In addition, the iron binding capacity (CTLF) was measured and the transferrin saturation index (SIT) was calculated. For the evaluation of oxidative metabolism, two parameters were used: concentrations of plasma malondialdehyde (MDA) and erythrocyte reduced glutathione (GSH). For of erythrocyte osmotic fragility evaluation, were used concentrations of 0.85% to 0.00% of sodium chloride (NaCl) and hemolysis was calculated in 50% of the samples. The hemogram showed a significant difference (P = 0.001) in erythrocytes, hemoglobin, globular volume (GV), mean globular hemoglobin concentration (MGHC), platelets and monocytes. The concentration of total plasma protein (PST) and fibrinogen did not show significant differences (P> 0.05). In the clinical biochemistry, a significant difference (P = 0.001) was observed in the concentration of glucose, magnesium, iron and SIT. In the concentrations of oxidative stress markers, a statistical difference was observed in the MDA dosage (P = 0.001). The EOS evaluation did not present statistical differences. The MDA indicated the presence of oxidative stress stimulus, as well as the discrete increase of GSH indicated a response to the production of antioxidants during the gestation period. During pregnancy, erythrocyte fragility and reduction in the number of circulating cells occurred, and the initial third of gestation requires a greater care / Os exames laboratoriais na medicina veterinária têm especial importância no que diz respeito à instituição de um diagnóstico eficiente. Na prática da clínica equina a patologia clínica veterinária facilita a interpretação de distúrbios que possam prejudicar o feto e a fêmea gestante. No período de prenhez ocorre maior consumo de oxigênio e consequentes alterações no consumo de energia e maior exposição ao estresse oxidativo, podendo causar reabsorção embrionária e abortamentos. O objetivo dessa pesquisa foi avaliar as principais alterações hematológicas, bioquímicas e do metabolismo oxidativo em éguas da raça Crioula no período da gestação. Foram colhidas amostras de sangue de 44 éguas dispostas em quatro diferentes grupos gestacionais, sendo onze éguas em cada um dos grupos (G0 = éguas vazias, G3 = 3 meses de gestação, G6 = 6 meses de gestação e G10 = 10 meses de gestação). A comprovação da gestação desses animais foi por meio de exames ultrassonográficos e palpação. As éguas foram avaliadas por meio de exame físico, hemograma e avaliação bioquímica. As éguas eram da mesma propriedade, submetidas ao mesmo manejo nutricional e sanitário. Foram avaliados o hemograma, a bioquímica clínica, no qual foram dosados ureia, creatinina, proteína sérica total (PST), albumina, globulinas, fosfatase alcalina (FA), gama glutamiltransferase (GGT), alanina aminotransferase (ALT), aspartato aminotransferase (AST), creatinaquinase (CK), cálcio, fósforo, magnésio, bilirrubina total, direta e indireta, lactato, colesterol, triglicérides, glicose, e a dosagem de ferro. Além da capacidade de ligação do ferro (CTLF) e calculado o índice de saturação de transferrina (IST). Para avaliação do metabolismo oxidativo foram utilizados dois parâmetros, as concentrações de malondialdeído plasmático (MDA) e glutationa reduzida eritrocitária (GSH). Para avaliação da fragilidade osmótica eritrocitária foram utilizadas concentrações de 0,85% a 0,00% de cloreto de sódio (NaCl) e foi calculado a hemólise em 50% das amostras. No hemograma foi observada diferença significativa (P=0,001) em eritrócitos, hemoglobina, volume globular (VG), concentração de hemoglobina globular média (CHGM), plaquetas e monócitos. A concentração de proteína plasmática total (PST) e fibrinogênio, não apresentaram diferenças significativas (P>0,05). Na bioquímica clínica observou-se diferença significativa (P=0,001) na concentração de glicose, magnésio, ferro e IST. Nas concentrações dos marcadores de estresse oxidativo se observou diferença estatística na dosagem de MDA (P=0,001). Já a avaliação da FOE não apresentou diferenças estatísticas. O MDA indicou a presença de estímulo ao estresse oxidativo, bem como o aumento discreto de GSH indicou uma resposta à produção de antioxidantes no período da gestação. Ocorreu maior fragilidade eritrocitária e redução no número de células circulantes, sendo que o terço incial da gestação requer maiores cuidados

Made available in DSpace on 2014-12-17T14:13:34Z (GMT). No. of bitstreams: 1 AdalgisaIM.pdf: 212398 bytes, checksum: 91a56cbfe357d683d0b60cf3fa34bf87 (MD5) Previous issue date: 2007-08-14 / Medicinal plants have been studied and used in the world. Lantana camara has medicinal properties and it has been used in folk medicine. The aim was to verify the effect of a lantana extract on the labeling of blood constituents with 99mTc, and to evaluate the effect of an aqueous extract of Lantana camara on the morphology of RBC withdrawn from Wistar rats. The results showed that lantana extract has decreased the fixation of radioactivity on the IF-P. This effect was not observed in the BC compartment and in IF-BC. The BC-%ATI was decreased in all concentrations tested when the BC was washed. The osmotic fragility assay and morphological analysis were carried out. In presence of the extract, the data obtained indicated that (i) an increase of the hemolysis and (ii) modifications on the morphology of RBC. These effects of the Lantana camara could be associated with some pharmacological properties of the chemical compounds of this studied extract / Extratos de plantas medicinais s?o utilizados amplamente em todo o mundo. Entretanto, efeitos biol?gicos associados aos mesmos n?o t?m sido investigados exaustivamente. Atrav?s do uso de suas folhas e flores a Lantana camara (Cambar? de espinho) tem sido usado para tratamento de v?rias doen?as na medicina popular. O presente estudo teve como objetivo verificar o efeito do extrato desta planta na marca??o de constituintes sang??neo com tecn?cio 99m, bem como a morfologia de hem?cias de ratos Wistar. Os resultados mostraram que o extrato de Lantana camara acarretou uma diminui??o de fixa??o de radioatividade na fra??o insol?vel do plasma. Este efeito n?o foi observado na c?lula e nem na fra??o insol?vel da c?lula. O percentual de atividade teve diminui??o em todas as concentra??es quando as c?lulas foram lavadas, o que n?o foi observado com o controle. O extrato estudado aumentou a fragilidade osm?tica das hem?cias e modificou a morfologia dessas c?lulas. Os efeitos do extrato de Lantana camara podem estar associados a algumas propriedades farmacol?gicas de componentes qu?micos do extrato estudado. O estudo teve car?ter multidisciplinar com a participa??o das seguintes ?reas do conhecimento: Radiobiologia, Bot?nica, Fitoterapia e Hematologia