Comparação de atividades de enzimas liquóricas com achados histopatológicos do sistema nervoso central de cães com encefalite por cinomose

A análise do líquido cerebrospinal demonstra ser uma ferramenta complementar viável e eficaz ao exame clínico-patológico do sistema nervoso, especialmente auxiliando no diagnóstico e prognóstico das suas inúmeras enfermidades. Porém, as variáveis apreciadas ao exame de rotina do liquor, nem sempre propiciam a detecção de anormalidades sutis frente a algumas situações neuropatológicas agudas, como por exemplo, nas viroses. Sendo assim, se faz necessário o aprofundamento do estudo do liquor com o escopo de se buscar técnicas mais sensíveis à identificação de alterações estruturais do tecido nervoso, bem como à avaliação do prognóstico do quadro clínico. E, recentemente, tem sido utilizada com sucesso em humanos a avaliação de marcadores bioquímicos, dentre os quais as atividades enzimáticas liquóricas da creatina quinase, lactato desidrogenase e aspartato aminotransferase. Sendo assim, idealizou-se o projeto de pesquisa, em tela, com o objetivo de se avaliar amostras liquóricas de cães acometidos por cinomose, com atenção especial às atividades enzimáticas, e sua correlação com achados histopatológicos do sistema nervoso central. Para tanto, foram colhidas amostras de LCR de 10 cães neurologicamente sadios e de 20 cães na fase neurológica da cinomose, as quais foram analisadas segundo a coloração, o aspecto, o pH, a densidade, a taxa de proteínas liquóricas totais e as atividades enzimáticas da lactato desidrogenase, da aspartato aminotransferase e da creatina quinase total e sua isoenzima CK-BB. Ademais fragmentos do encéfalo e medula espinhal também foram colhidos para posterior avaliação histopatológica. Os resultados obtidos foram capazes de demonstrar, principalmente a origem neurológica do aumento das atividades enzimáticas liquóricas, principalmente da CK e, ainda, a correlação entre o grau...Evaluation of the cerebrospinal fluid is an important and efficient tool in the clinical-pathologic examination of the central nervous system, helping in the diagnosis and prognosis of several disorders. However, the variables presented in the cerebrospinal fluid not always allow the detection of acute neuropathology, such as viruses. It is necessary more studies with the purpose to obtain more sensitive techniques to identify structural changes in the nervous system, as well as the evaluation and prognosis of clinical signs. Recently, the evaluation of biochemical ma rkers , such as cerebrospinal enzyme activity, lactate dehidrogenase and aspartate aminotransferase, has been used in humans. Thus, the aim of the present study is to evaluate cerebrospinal samples of dogs with canine distemper, with focus on enzymatic activity and its correlation with histopathological finding of the central nervous system. For that purpose, samples of the CSF were collected from 10 dogs clinically healthy and 20 dos presenting neurological signs of canine distemper. The samples were evaluated for color, aspect, pH, density, total protein in CSF and enzyme activities (Iactate dehidrogenase, aspartate aminotransferase and total creatine kinase and its isoenzyme CK-BB). Moreover, fragments of the brain and spinal marrow were collected for histopathological evaluation. The results were capable to demonstrate the neurological origin of the increase in CSF enzyme activities, especially of CK and also the correlation between the degree of enzyme activities and the extent of desmielinizing injury found in the central nervous system.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Physical-chemical analysis of the cerebrospinal fluid of healthy dogs submitted to different storage periods and temperatures

Disfunções envolvendo o sistema nervoso são de grande importância na Medicina Veterinária, pois tratam-se de enfermidades de elevada incidência e com poucos subsídios auxiliares no seu diagnóstico, prognóstico e na avaliação de terapias empregadas. Ainda hoje, o diagnóstico baseia-se, em grande parte, no histórico e no exame clínico neurológico. Dessa forma, a análise dos constituintes do fluido cefalorraquidiano torna-se uma das poucas alternativas de acesso clínico ao sistema nervoso central (SNC). Mesmo com a grande utilidade do exame físico-químico e citoscópico do liquor na neurologia veterinária, poucos são os estudos sobre a estabilidade dos seus constituintes sob estocagem. Dessa forma, o presente trabalho teve como finalidade verificar a influência da temperatura e do tempo de conservação nas características físico-químicas do liquor de cães hígidos. Para tanto, foram coletadas amostras de LCR, através da punção da cisterna cerebelo-medular de cães clinicamente sadios, as quais foram submetidas à análise da densidade específica, do pH, da glicorraquia, das proteínas totais e das atividades das enzimas creatina quinase (CK) e aspartato aminotransferase (AST), após conservá-las em diferentes temperaturas (25°C, 4°C e -4°C) e por diferentes períodos de tempo (logo após a colheita, 24 horas, 48 horas, uma semana e um mês). Dentre os resultados obtidos, foi possível verificar, principalmente, que houve estabilidade dos parâmetros estudados por até um mês de estocagem nas amostras mantidas sob a temperaturas de congelamento de -4°C.Disorders involving the nervous system have a great importance in veterinary medicine because they have a high incidence and few auxiliary tools for their diagnostic, prognostic and evaluation of the employed therapy. Today, the diagnostic is based, mainly, on the patient history and neurologic examination. Hence, evaluation of the cerebrospinal fluid elements is one of the few alternatives to clinically access the central nervous system (CNS). Even with the great usefullness of the physical-chemical and cytoscopy exams of the CSF in veterinary neurology, there are few studies concerning the stability of its elements under freezing storage. The present study was aimed at verifing the influence of temperature and period of conservation on physical-chemical characteristics of the CSF of healthy dogs. For that purpose, CSF samples were collected by puncture of the cisterna magna of dogs clinically healthy, and then were analysed for density, pH, glucorrhachia, total proteins and activity of the enzymes creatine kinase (CK) and aspartate aminotransferase (AST), after storage in different temperatures (25°C, 4°C and -4°C) and periods (immediately after collection and after 24 hours, 48 hours, a week and a month). Regarding the obtained results it was possible to verify that the parameters studied were stable up to a month of storage, under freezing at -4°C

Caracteres físico-químicos e citológicos do liquor de cães em diferentes fases da cinomose

O líquido cerebrospinal é útil no diagnóstico, acompanhamento e prognóstico de enfermidades neurológicas caninas. Dentre elas, a cinomose é considerada a encefalite mais comum nos cães e inúmeras alterações podem ocorrer neste fluido frente a esta enfermidade. Sendo assim, diante da possível verificação de anormalidades precoces relacionadas com esta virose, amostras liquóricas de cães portadores do vírus da cinomose, na fase neurológica e não neurológica foram avaliadas quanto à coloração, aspecto, pH, densidade, glicose, proteínas totais, celularidade e comparadas com amostras liquóricas de cães hígidos. Os parâmetros coloração, aspecto, pH, densidade e glicose mostraram-se semelhantes entre animais acometidos pela cinomose, independentemente da fase evolutiva da doença, e animais normais. A concentração liquórica de proteínas totais mostrou-se mais elevada nos animais portadores de sinais neurológicos, bem como a celularidade total, cuja pleocitose foi observada em 50% dos cães deste mesmo grupo, com predominância de mononucleares.The cerebrospinal fluid is useful to diagnosis, monitoring and prognosis canine neurological diseases. Among them distemper is considered the most common encephalitis in dogs and several alterations can be observed in this fluid with this disease. Since the early abnormalities related to this virus were possibly verified, CSF samples of dogs infected by distemper virus, with or without neurological signs were collected. The samples were evaluated according to colour, turbidity, pH, specific gravity, glucose, total proteins, and cytological examination, and then were compared to CSF samples of healthy dogs. The parameters related to colour, turbidity, pH, specific gravity, glucose showed to be similar between all animals studied in this attempt. The CSF total protein concentration revealed higher values in animals with neurological signs of distemper, as the celularity, whose pleocytosis with predominance of mononuclear cells was observed in 50% of dogs among this group.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Agarose gel electrophoresis of cerebrospinal fluid proteins of dogs after sample concentration using a membrane microconcentrator technique

Background: Cerebrospinal fluid (CSF) is produced in the cerebral ventricles through ultrafiltration of plasma and active transport mechanisms. Evaluation of proteins in CSF may provide important information about the production of immunoglobulins within the central nervous system as well as possible disturbances in the blood-brain barrier. Objective: the objective of this study was to measure the concentration and fractions of protein in CSF samples using a membrane microconcentrator technique followed by electrophoresis, and to compare the protein fractions obtained with those in serum. Methods: CSF samples from 3 healthy dogs and 3 dogs with canine distemper virus infection were concentrated using a membrane microconcentrator having a 0.5 to 30,000 d nominal molecular weight limit (Ultrafree, Millipore, Billerica, MA, USA). Protein concentration was determined before and after concentration. Agarose gel electrophoresis was done on concentrated CSF samples, serum, and serial dilutions of one of the CSF samples. Results: Electrophoretic bands were clearly identified in densitometer tracings in CSF samples with protein concentrations as low as 1.3 g/dL. The higher CSF protein concentration in dogs with distemper was mainly the result of increased albumin concentration. Conclusion: the microconcentrating method used in this study enables characterization of the main protein fractions in CSF by routine electrophoresis and may be useful for interpreting the underlying cause of changes in CSF protein concentration

Cerebrospinal fluid collection in dogs: modification of previous technique

Unlike the already described techniques, which are based on imaginary lines among extremities or bone projections, this research describes a collection technique modification of cerebrospinal fluid (CSF) in dogs, in the atlantooccipital space. The palpation of bone structures in this joint, plus the supported directioning of the needle, does make the collection easy, even by professionals which have no experience in this kind of procedure. The applied technique enabled the collection of adequate volumes of limpid and colorless CSF of 50 healthy dogs in the first attempt of collection. There was no contamination with blood during the procedure, what made possible the correct interpretation of laboratory parameters usually examined in CSF samples