Resultado da pesquisa (6)

Termo utilizado na pesquisa Neurons

#1 - Quantification of the neurons of myenteric plexus of the bat molossus rufus

Abstract in English:

There are no studies that characterize the enteric nervous system (ENS) bats. The organization and density of myenteric neurons may vary according to the animal species, as well as the segment of the digestive tube considered. The nitric oxide is one of the key neurotransmitters present in the myenteric neurons, acting as a mediator in the smooth muscle relaxation. These neurons are evidenced by immunohistochemistry of nitric oxide synthase (NOS) or by NADPH-diaphorase histochemistry. In this sense, this study aimed to characterize the total neuronal population and subpopulation NADPH-d+ of the myenteric plexus present in the jejunum of the insectivore species Molossus rufus quantitatively. Five specimens were collected of M. rufus in a buffer area of the “Reserva Biológica das Perobas” in the microregion of Cianorte/PR. After the euthanasia, in a chamber saturated with isoflurane, segments were collected from the small intestine corresponding to the jejunum intended for two techniques for neuronal marking, Giemsa and NADPH-diaphorase, and a fragment to the histological technique of hematoxylin-eosin and Masson’s trichrome. All the procedures were approved by the “Comitê de Ética no Uso de Animais Unipar” (CEUA - protocol No. 34347/2017) and the “Instituto Chico Mendes de Conservação da Biodiversidade” (ICMBio - protocol No. 60061-1) The histological sections allowed to highlight the location of the myenteric plexus between the longitudinal and circular layers of the muscular tunic. The myenteric plexus had an average of total neuronal population (neurons Giemsa+) of 279.23 neurons/mm2, being the nitrergic neurons (neurons NADPH-d+) represented 20.4% of this total population, with an average of 58.14 neuron/mm2. Therefore, the collected data are consistent with previous studies in other mammalian species concerning the location of the myenteric plexus, as well as the neural myenteric proportion NADPH-d+ compared with the population of neurons Giemsa+. The gaps in the knowledge of ENS of bats limits comparative intraspecific and interspecific studies.

Abstract in Portuguese:

Não há estudos que caracterizem o sistema nervoso entérico (SNE) destes animais, configurando uma lacuna no conhecimento quanto à biologia destes indivíduos. A organização e densidade dos neurônios mientéricos podem variar de acordo com a espécie animal bem como o segmento do tubo digestório considerado. O óxido nítrico é um dos principais neurotransmissores presentes nos neurônios mientéricos, atuando como mediador no relaxamento do músculo liso gastrointestinal, de modo que estes neurônios são evidenciados igualmente pela imunohistoquímica da óxido nítrico-sintase (NOS) ou pela histoquímica da NADPH-diaforase. Neste sentido, objetivou-se caracterizar quantitativamente a população neuronal total e subpopulação NADPH-d+ do plexo mientérico presente no jejuno da espécie Molossus rufus de hábito alimentar insetívoro. Foram coletados cinco espécimes de M. rufus em área de amortecimento da Reserva Biológica das Perobas na microrregião de Cianorte/PR. Após a eutanásia, em câmara saturada com isoflurano, foram coletados segmentos do intestino delgado correspondentes ao jejuno destinados a duas técnicas para marcação neuronal, Giemsa e NADPH-diaforase e, um fragmento para a técnica histológica de hematoxilina-eosina e tricômio de Masson. Todos os procedimentos realizados foram aprovados pelo Comitê de Ética no Uso de Animais da Unipar (CEUA - protocolo nº 34347/2017) e pelo Instituto Chico Mendes de Conservação da Biodiversidade (ICMBio - protocolo nº 60061-1) Os cortes histológicos possibilitaram evidenciar a localização do plexo mientérico entre os estratos longitudinal e circular da túnica muscular. Neurônios Giemsa+ apresentaram uma média de 279,23 neurônios/mm2, já os neurônios nitrérgicos apresentaram em média 20,4% da população neuronal mientérica total, sendo evidenciados 58,14 neurônios NADPH-d+/mm2. Portanto, os dados coletados mostram-se condizentes com estudos anteriores em outras espécies de mamíferos quanto à localização do plexo mientérico, bem como, a proporção neuronal mientérica NADPH-d+ comparada com a população de neurônios Giemsa+. As lacunas existentes quanto ao conhecimento do SNE de morcegos limita possíveis inferências em comparativo intraespecífico e interespecífico.


#2 - A new experimental model of intrinsic denervation in ileum from wistar rats through intramural microinjections of benzalkonium chloride

Abstract in English:

Extensive literature is available about the intrinsic denervation of segments of the digestive tube through the application of CB in the serosa of the viscera. However, this technique has some disadvantages like causing peritonitis, flanges and high mortality, limiting its use in humans. The aim of the present study was to evaluate the feasibility of benzalkonium chloride (CB) to induce intrinsic chemical denervation, through applications of CB in the intramural ileum of wistar rats, as well as deepen the knowledge about the evolution of neuronal injury caused in the process. We used 40 rats, divided into two groups (control-GC and benzalkonium GB) of 20 animals each, divided into four sub-groups according to the time of postoperative assessment of 24, 48 hours, 30 and 90 days. The animals were submitted to intramural microinjections of sterile saline solution 0.9% (GC) or benzalkonium chloride (GB) in ileal portion, and subsequent histopathological analysis and immunohistochemistry for evaluation of neuronal injury. A significant decrease (p<0.05) was found of the neuronal myenteric count over time in groups, GB3, GB4 and GB2. The specific positive immunolabeling for H2AX and Caspase-3 confirmed the results obtained in the histopathological evaluation, denoting the ignition of irreversible cell injury in 24 hours, evolving into neuronal apoptosis in 48 hours after application of the CB 0.3%. Under the conditions in which this work was conducted, it can be concluded that the application of CB 0.3% by means of microinjections intramural in the ileal wall is able to induce intrinsic chemical denervation of the diverticulum of wistar rats and that the main mechanism of neuronal death is induction of apoptosis.

Abstract in Portuguese:

Existe vasta literatura sobre a desnervação intrínseca de segmentos do tubo digestório através da aplicação de CB na serosa da víscera. Entretanto, essa técnica tem a desvantagem de causar peritonite, formação de bridas e alta mortalidade, não sendo factível para eventuais utilizações em humanos. O objetivo do presente estudo foi avaliar a viabilidade do Cloreto de benzalcônio (CB) induzir desnervação química intrínseca, por meio de aplicações intramurais em íleo de ratos wistar, além de aprofundar o conhecimento sobre a evolução da lesão neuronal causada neste processo. Foram utilizados 40 ratos, distribuídos em dois grupos (controle- GC e benzalcônio GB) de 20 animais cada, subdivididos em quatro subgrupos de acordo com o tempo de avaliação pós-operatória de 24, 48 horas, 30 e 90 dias. Os animais foram submetidos à microinjeções intramurais de solução salina estéril 0,9% (GC) ou de cloreto de benzalcônio (GB) em porção ileal, e posterior análise histopatológica e imuno-histoquímica, para avaliação da lesão neuronal. Houve diminuição significativa (p<0,05) na contagem neuronal mientérica ao longo do tempo nos grupos GB2, GB3 e GB4. A imunomarcação específica positiva para H2AX e Caspase-3 confirmou os resultados obtidos na avaliação histopatológica, denotando início da lesão celular irreversível em 24 horas, evoluindo para apoptose neuronal em 48 horas após a aplicação do CB 0,3%. Nas condições em que este trabalho foi conduzido, é possível concluir que a aplicação de CB 0,3% por meio de microinjeções intramurais na parede ileal é capaz de induzir desnervação química intrínseca da porção ileal de ratos wistar e que o principal mecanismo de morte neuronal é a indução de apoptose.


#3 - Isolation and culture of neurons and neurospheres from chicken brain cortex, 33(Supl.1):45-50

Abstract in English:

ABSTRACT.- Crepaldi C.R., Merighe G.K.F., Laure H.J., Rosa J.C., Meirelles F.V. & Cerqueira César M. 2013. [Isolation and culture of neurons and neurospheres from chicken brain cortex.] Isolamento e cultivo de neurônios e neuroesferas de córtex cerebral aviar. Pesquisa Veterinária Brasileira 33(Supl.1):45-50. Laboratório de Neurociência e Proteômica, Faculdade de Zootecnia e Engenharia de Alimentos, Universidade de São Paulo, Av. Duque de Caxias Norte 225, Pirassununga, SP 13635-900, Brazil. E-mail: mccesar@usp.br Cell culture methods are used for studies of protein interactions in neural cells, helping to detect the interactome of proteins linked to generation of central nervous system diseases. For this reason, neural cells and neurospheres isolated from cortical chicken brain are a current model for studies of neurological diseases, such as epilepsy. Chicken brain has key characteristics on its proteome, with a differential expression of proteins linked to energy metabolism, some of them (VDAC 1 and VDAC 2) play an important role in understanding mechanism of refractory epilepsy. Using the methods described, we found neurospheres, in which cells grow in structures with the ideal diameter of 100-200µm within seven days after isolation. Neurospheres differentiation was obtained after adhesion of these cells to surfaces coated with poly-D-Lysine, detected by migration of fibers inside them. Unlike neurospheres, neurons extended neurites after 11 days of isolation. Here we describe a method to isolate and culture neurons and neurospheres from chicken cerebral cortex. Such “in vitro” model can be utilized on studies of neuronal protein differential expression and interaction. Cultures of isolated neurons represent an accessible model on studies of apoptosis and channel blockers of key proteins linked to brain metabolism.

Abstract in Portuguese:

RESUMO.- Crepaldi C.R., Merighe G.K.F., Laure H.J., Rosa J.C., Meirelles F.V. & Cerqueira César M. 2013. [Isolation and culture of neurons and neurospheres from chicken brain cortex.] Isolamento e cultivo de neurônios e neuroesferas de córtex cerebral aviar. Pesquisa Veterinária Brasileira 33(Supl.1):45-50. Laboratório de Neurociência e Proteômica, Faculdade de Zootecnia e Engenharia de Alimentos, Universidade de São Paulo, Av. Duque de Caxias Norte 225, Pirassununga, SP 13635-900, Brazil. E-mail: mccesar@usp.br Métodos de cultivo celular são convenientes na realização de análises funcionais de alterações/interações protéicas das células neuronais, auxiliando a decifrar o interactoma de proteínas chaves na neurogênese de doenças do Sistema Nervoso Central. Por esse motivo, culturas de neurônios e neuroesferas isolados do córtex cerebral aviar representam um modelo acessível para o estudo de diversas doenças neurológicas, tal como a epilepsia. A espécie aviar apresenta peculiaridades em seu proteoma neuronal, visto a presença de uma expressão diferenciada de proteínas chaves no metabolismo energético cerebral, algumas destas (VDAC1 e VDAC2) desempenham papel importante na compreensão do mecanismo da epilepsia refratária. A metodologia estabelecida no presente estudo obteve cultivo de neuroeferas, onde as células cresceram tipicamente em aglomerados atingindo, dentro de 7 dias, o diâmetro ideal de 100-200 µm. A diferenciação celular das neuroesferas foi obtida após a aderência destas às placas tratadas com poli-D-lisina, evidenciada pela migração de fibras do interior da neuroesfera. Ao contrário das neuroesferas, os neurônios em cultivo extenderam seus neuritos após 11 dias de isolamento. Tal modelo in vitro pode ser utilizado com sucesso na identificação das variáveis neuroproteômicas, propiciando uma avaliação global das alterações dinâmicas e suas interações protéicas. Tal modelo pode ter aplicações em estudos dos efeitos de indutores da morte celular e bloqueadores de canais de membrana mitocondriais em proteínas chaves do metabolismo energético cerebral.


#4 - Effects of ascorbic acid supplementation in ileum myenteric neurons of streptozotocin-induced diabetic rats, p.295-302

Abstract in English:

ABSTRACT.- Silverio S.M., Mari R.B, Clebis N.K., Scoz J.R., Germano R.M., Major J.A.A., Bombonato P.P. & Stabille S.R. 2009. The effects of ascorbic acid supplementation in ileum myenteric neurons of streptozotocin-induced diabetic rats. Pesquisa Veterinária Brasileira 29(4):295-302. Departamento de Cirurgia, Setor de Anatomia dos Animais Domésticos e Silvestres, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Av. Prof. Dr. Orlando Marques de Paiva 87, São Paulo, SP 05508-270, Brazil. E-mail: remari@usp.br The exacerbation of the oxidative stress and of the polyol pathway which impair damage myenteric plexus are metabolic characteristics of diabetes. The ascorbic acid (AA) is an antioxidant and an aldose reductase inhibitor, which may act as neuroprotector. The effects of AA supplementation on the density and cellular body profile area (CP) of myenteric neurons in STZ-induced diabetes in rats were assessed. Four groups with five animals each were formed: normoglycemic (C); diabetic (D); AA-treated diabetic (DS) and AA-treated normoglycemic (CS). Dosagen of 50mg of AA were given, three times a week, for each animal (group DS and CS). Ninety days later and after euthanasia, the ileum was collected and processed for the NADPH-diaphorase technique. There were no differences (P>0.05) in the neuronal density among the groups. The CP area was lower (P<0.05) in the DS and CS groups, with a higher incidence of neurons with a CP area exceeding 200mm2 for groups C and D. The AA had no influence on the neuronal density in the ileum but had a neuroprotective effect, preventing the increase in the CP area and allowing a higher number of neurons with a CP area with less than 200mm2.

Abstract in Portuguese:

ABSTRACT.- Silverio S.M., Mari R.B, Clebis N.K., Scoz J.R., Germano R.M., Major J.A.A., Bombonato P.P. & Stabille S.R. 2009. The effects of ascorbic acid supplementation in ileum myenteric neurons of streptozotocin-induced diabetic rats. Pesquisa Veterinária Brasileira 29(4):295-302. Departamento de Cirurgia, Setor de Anatomia dos Animais Domésticos e Silvestres, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Av. Prof. Dr. Orlando Marques de Paiva 87, São Paulo, SP 05508-270, Brazil. E-mail: remari@usp.br The exacerbation of the oxidative stress and of the polyol pathway which impair damage myenteric plexus are metabolic characteristics of diabetes. The ascorbic acid (AA) is an antioxidant and an aldose reductase inhibitor, which may act as neuroprotector. The effects of AA supplementation on the density and cellular body profile area (CP) of myenteric neurons in STZ-induced diabetes in rats were assessed. Four groups with five animals each were formed: normoglycemic (C); diabetic (D); AA-treated diabetic (DS) and AA-treated normoglycemic (CS). Dosagen of 50mg of AA were given, three times a week, for each animal (group DS and CS). Ninety days later and after euthanasia, the ileum was collected and processed for the NADPH-diaphorase technique. There were no differences (P>0.05) in the neuronal density among the groups. The CP area was lower (P<0.05) in the DS and CS groups, with a higher incidence of neurons with a CP area exceeding 200mm2 for groups C and D. The AA had no influence on the neuronal density in the ileum but had a neuroprotective effect, preventing the increase in the CP area and allowing a higher number of neurons with a CP area with less than 200mm2.


#5 - The number and profile of reactive NADH-d and NADPH-d neurons of myenteric plexus of six-month-old rats are different in the cecum portions, p.241-248

Abstract in English:

ABSTRACT.- Silva E.A., Natali M.R.M. & Prado I.M.M. 2008. The number and profile of reactive NADH-d and NADPH-d neurons of myenteric plexus of six-month-old rats are different in the cecum portions. Pesquisa Veterinária Brasileira 28(5):241-248. Departamento de Cirurgia, Faculdade de Medicina Veterinária e Zootecnia, USP, Cidade Universitária, Av. Prof. Dr. Orlando Marques de Paiva 87, São Paulo, SP 05508-270. E-mail: elizangela@usp.br Whole-mount preparations were prepared and submitted to NADH-diaphorase and NADPH-diaphorase histochemistry techniques. The myenteric plexus arrangement and the number of neurons were comparatively evaluated among the different portions of the cecum. The neurons from the apical and basal regions were distributed in classes at intervals of 100µm2, the means of the corresponding intervals being compared. The ganglia, in both techniques, were often connected by fine bundles, which became thicker in the mesenteric region and in the region next to the cecal ampulla. The number of positive NADH-d neurons was higher than that of NADPH-d neurons in all portions, from both regions. The numbers of reactive NADH-d e NADPH-d neurons were significantly different among the different portions of the cecum, except for the antimesenteric basal and intermediate basal regions, considering the NADH-d neurons. The profile area for the reactive NADH-d e NADPH-d neurons was higher in the apical region than in the basal area. Differences in arrangement, distribution and size of positive NADH-d e NADPH-d neurons in the different cecum portions evidenced the importance of the subdivision of the analyzed organ.

Abstract in Portuguese:

ABSTRACT.- Silva E.A., Natali M.R.M. & Prado I.M.M. 2008. The number and profile of reactive NADH-d and NADPH-d neurons of myenteric plexus of six-month-old rats are different in the cecum portions. Pesquisa Veterinária Brasileira 28(5):241-248. Departamento de Cirurgia, Faculdade de Medicina Veterinária e Zootecnia, USP, Cidade Universitária, Av. Prof. Dr. Orlando Marques de Paiva 87, São Paulo, SP 05508-270. E-mail: elizangela@usp.br Whole-mount preparations were prepared and submitted to NADH-diaphorase and NADPH-diaphorase histochemistry techniques. The myenteric plexus arrangement and the number of neurons were comparatively evaluated among the different portions of the cecum. The neurons from the apical and basal regions were distributed in classes at intervals of 100µm2, the means of the corresponding intervals being compared. The ganglia, in both techniques, were often connected by fine bundles, which became thicker in the mesenteric region and in the region next to the cecal ampulla. The number of positive NADH-d neurons was higher than that of NADPH-d neurons in all portions, from both regions. The numbers of reactive NADH-d e NADPH-d neurons were significantly different among the different portions of the cecum, except for the antimesenteric basal and intermediate basal regions, considering the NADH-d neurons. The profile area for the reactive NADH-d e NADPH-d neurons was higher in the apical region than in the basal area. Differences in arrangement, distribution and size of positive NADH-d e NADPH-d neurons in the different cecum portions evidenced the importance of the subdivision of the analyzed organ.


#6 - Assessment of NADPH-diaphorase stained myenteric neurons of the jejunum of diabetic rats supplemented with ascorbic acid, p.95-102

Abstract in English:

ABSTRACT.- Silverio S.M., Mari R.B., Clebis N.K., Scoz J.R., Germano R.M., Agreste F., Bombonato P.P. & Stabille S.R. 2008. Assessment of NADPH-diaphorase stained myenteric neurons of the jejunum of diabetic rats supplemented with ascorbic acid. Pesquisa Veterinária Brasileira 28(2):95-102. Departamento de Ciências Biológicas, UNIPAR, Campus-Paranavaí, Av. Huberto Brüning 360, Jardim Santos Dumont, Paranavaí, PR 87706-490, Brazil. E-mail: srstabille@wnet.com.br The relation between hyperglycemia and diabetic neuropathy has already been demonstrated in some studies. Among the theories proposed for its etiology the oxidative stress stands out. The performance of nitric oxide as a link between the metabolic and vascular neuropathogenic factors that triggers the diabetic neuropathy has already been put forward. This study aimed to assess the quantification and measurements of the cell body profile area (CBPA) of NADPH-diaphorase reactive (NADPH-dp) myenteric neurons of the jejunum of diabetic rats (induced by streptozotocin) supplemented with Ascorbic Acid (AA). These changes in the myenteric neurons seem to be related to the gastrointestinal disturbances observed in diabetes mellitus (DM). Twenty male Wistar rats (Rattus norvegicus) were distributed in 4 groups (n=5): controls (C), control supplemented (CS), diabetic (D), and diabetic suplemented (DS). DM was induced by estreptozotocin (50mg/kg body wt). One week after the induction and confirmation of the DM (glycemia exam), animals of the groups CS and DS received 50mg of AA three times a week by gavage. After 90 days of experiment, the animals were anesthetized with lethal thiopental dose (40mg/kg) and the collected jejunum processed for the histochemistry NADPH-diaphorase technique. Whole-mount preparations were obtained for quantitative and morphometric analysis of the myenteric neurons. A quantity of jejunum neurons in the Group D (96±7.5) was not different (P>0.05) from Group DS (116±8.08), C (92±9.7), and CS (81±5.4), but in Group DS the quantity was higher (P<0.05) than in Group C and CS. The CBPA of neurons from Group D (189.50±2.68µm2) and DS (195.92±3.75µm2) were lower (P<0.05) than from Group C (225.13±4.37µm2) and CS (210.23±3.15µm2). The streptozotocin-induced DM did not change the jejunum-ileum area, the jejunum myenteric plexus space organization and the density of NADPH-dp neurons. The 50g AA-supplementation, three times a week, during 90 days, did not decrease hyperglycemia; however, it had a neuroprotective effect on the myenteric neurons, minimizing the increase on the CBPA of NADPH-dp neurons and increasing the amount of NADPD-dp neurons.

Abstract in Portuguese:

ABSTRACT.- Silverio S.M., Mari R.B., Clebis N.K., Scoz J.R., Germano R.M., Agreste F., Bombonato P.P. & Stabille S.R. 2008. Assessment of NADPH-diaphorase stained myenteric neurons of the jejunum of diabetic rats supplemented with ascorbic acid. Pesquisa Veterinária Brasileira 28(2):95-102. Departamento de Ciências Biológicas, UNIPAR, Campus-Paranavaí, Av. Huberto Brüning 360, Jardim Santos Dumont, Paranavaí, PR 87706-490, Brazil. E-mail: srstabille@wnet.com.br The relation between hyperglycemia and diabetic neuropathy has already been demonstrated in some studies. Among the theories proposed for its etiology the oxidative stress stands out. The performance of nitric oxide as a link between the metabolic and vascular neuropathogenic factors that triggers the diabetic neuropathy has already been put forward. This study aimed to assess the quantification and measurements of the cell body profile area (CBPA) of NADPH-diaphorase reactive (NADPH-dp) myenteric neurons of the jejunum of diabetic rats (induced by streptozotocin) supplemented with Ascorbic Acid (AA). These changes in the myenteric neurons seem to be related to the gastrointestinal disturbances observed in diabetes mellitus (DM). Twenty male Wistar rats (Rattus norvegicus) were distributed in 4 groups (n=5): controls (C), control supplemented (CS), diabetic (D), and diabetic suplemented (DS). DM was induced by estreptozotocin (50mg/kg body wt). One week after the induction and confirmation of the DM (glycemia exam), animals of the groups CS and DS received 50mg of AA three times a week by gavage. After 90 days of experiment, the animals were anesthetized with lethal thiopental dose (40mg/kg) and the collected jejunum processed for the histochemistry NADPH-diaphorase technique. Whole-mount preparations were obtained for quantitative and morphometric analysis of the myenteric neurons. A quantity of jejunum neurons in the Group D (96±7.5) was not different (P>0.05) from Group DS (116±8.08), C (92±9.7), and CS (81±5.4), but in Group DS the quantity was higher (P<0.05) than in Group C and CS. The CBPA of neurons from Group D (189.50±2.68µm2) and DS (195.92±3.75µm2) were lower (P<0.05) than from Group C (225.13±4.37µm2) and CS (210.23±3.15µm2). The streptozotocin-induced DM did not change the jejunum-ileum area, the jejunum myenteric plexus space organization and the density of NADPH-dp neurons. The 50g AA-supplementation, three times a week, during 90 days, did not decrease hyperglycemia; however, it had a neuroprotective effect on the myenteric neurons, minimizing the increase on the CBPA of NADPH-dp neurons and increasing the amount of NADPD-dp neurons.


Colégio Brasileiro de Patologia Animal SciELO Brasil CAPES CNPQ UNB UFRRJ CFMV