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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Central role for Sonic hedgehog-triggered pericytes in hindbrain choroid plexus development

Yang, Peter 25 February 2014 (has links)
The choroid plexus is an organ within each brain ventricle comprised of elaborate folds of epithelium (CPe) and vasculature. It performs numerous functions essential for brain development and health, including secretion of cerebrospinal fluid (CSF) and acting as the blood-CSF barrier. Functionality requires: (1) that CPe and vasculature develop in register and in close proximity, so that the CPe ensheaths the vasculature at a high surface area to volume ratio, which permits efficient CSF secretion; and (2) that CPe barrier integrity is sustained throughout choroid plexus expansion. Genetic experiments in mouse embryos have identified a central role for Sonic hedgehog (Shh) in coordinating these developmental challenges. Specifically, Shh is secreted by differentiated CPe and drives choroid plexus expansion. In the absence of Shh, a hypoplastic choroid plexus forms, which is deficient in CPe, vasculature, and villous folds. Two choroid plexus cell populations respond to Shh: (1) rhombic lip-resident CPe progenitor cells and (2) vascular pericytes. Here, I present evidence that canonical Shh signaling to CPe progenitors alone is insufficient to fully drive their proliferation at normal rates. Rather, Shh-triggered pericytes appear to secondarily boost CPe progenitor cell proliferation, in addition to acting in vascular development. Shh-triggered pericytes also appear necessary for formation of the characteristic folds of the choroid plexus. Thus, pericytes coordinate the expansion of choroid plexus epithelium and vasculature. Notch signaling was also explored and was found to inhibit the differentiation of CPe progenitors, maintaining them in a proliferative state. Notch activation in CPe progenitors leads to invaginated tubules from the overproliferating CPe progenitor domain, without associated vascular growth or villous folds. Folding morphogenesis may thus be regulated by vascular components such as pericytes, and require that vascular growth match CPe growth. To identify Shh-induced pericyte signaling programs that might underlie these developmental processes, expression profiling was performed on dsRed-labeled pericytes isolated from Shh-deficient versus wild-type choroid plexuses. Candidate genes, including several involved in lipid metabolism, were identified. Collectively, this work points to pericytes as central in orchestrating the coordinated elaboration of multiple choroid plexus cell types, producing the complex tissue architecture required for efficient CSF production.
82

Gial cell line-derived neutrotrophic factor expression in proliferating intestinal smooth muscle cells is important for enteric neuron survival

HAN, TIAN YU 28 September 2012 (has links)
Normal intestinal functions are coordinated by enteric neurons within the enteric nervous system (ENS). In the embryonic and neonatal gut, enteric neuron survival is dependent on the expression of glial cell line-derived neurotrophic factor (GDNF) from its targets of innervation - the intestinal smooth muscle cells (ISMC). In the inflamed adult intestine, enteric neuron loss is immediately followed by ISMC proliferation, resulting in severe disruption of normal intestinal functions. Although GDNF can support the survival of postnatal enteric neurons, whether adult ISMC can secrete GDNF and support neuron survival is unclear. Results from qPCR analysis showed that freshly isolated adult ISMC have acquired the ability to express GDNF at the onset of proliferation, in vitro. Western blot analysis indicates that GDNF continues to be upregulated in ISMC at Passage 2 (P2), but its expression is decreased after long periods of proliferation at Passage 10 (P10). A neuron survival bioassay suggests that GDNF expression is correlated with enteric neuron survival. Results showed that P2 ISMC or conditioned media (CM) - but not P10 ISMC and CM, significantly increased enteric neuron survival. In subsequent experiments, the RET tyrosine kinase inhibitor vandetanib was used to block GDNF receptor-ligand interactions, and anti-GDNF neutralizing antibody was used to sequester soluble GDNF within the culture media. Both methods were successful at decreasing myenteric neuron survival. Furthermore, abolishing GDNF expression in P2 ISMC with GDNF siRNA also resulted in a decreased myenteric neuron survival. The above observations suggest that ISMC-derived GDNF is important in supporting myenteric neuron survival in vitro. / Thesis (Master, Neuroscience Studies) -- Queen's University, 2012-09-28 09:43:23.968
83

Morphological and Immunohistochemical Patterns of the Intrinsic Ganglionated Nerve Plexus in the Mouse Heart / Pelės širdies vidusieninio nervinio rezginio morfologija ir imunohistochemija

Rysevaitė, Kristina 22 September 2011 (has links)
Intrinsic neural plexus of the mouse heart has not been adequately investigated despite the extensive use of this species in experimental cardiology. Both the normal and the genetically modified mice are excellent models for investigations of molecular mechanisms of cardiac arrhythmia associated with disbalance between sympathetic and parasympathetic neural inputs to the heart. The purpose of this study was to determine the topographical and structural organization of the mouse cardiac neural plexus, also to determine the distribution of cholinergic (parasyphatetic), adrenergic (symphatetic), and sensory (peptidergic) neural components in whole-mount mouse heart preparations using double immunohistochemical labeling. Results showed, that despite substantial anatomic differences in the number and distribution of epicardiac ganglia, structural organization of intrinsic ganglionated plexus in the mouse heart corresponds in general to that of other mammalian species, including the human. Majority of nerves and neural bundles in the mouse heart are mixed, but a lot of them express either adrenergic or cholinergic phenotype. Therefore, the selective stimulation and/or ablation of the functionally distinct intrinsic neural pathways appears fairly available in the mouse heart model and this should allow further investigations on specific effects of distinct intrinsic nerves and ganglia on cardiac function. / Intrakardinė nervų sistema atlieka svarbų vaidmenį reguliuodama širdies ritmą, miokardo laidumą ir susitraukimo jėgą bei vainikinių arterijų tonusą. Tyrinėjant simpatinės-parasimpatinės nervų sistemos tonusų disbalansą, širdies ritmo sutrikimų bei miokardo išemijos molekulinius mechanizmus, pastaruoju metu eksperimentiniais modeliais yra pasirenkamos įvairios genetiškai modifikuotų laboratorinių pelių linijos, tačiau pelės širdies vidusieninis nervinis rezginys iki šiol nebuvo dažnas neuroanatominių tyrimų objektas. Šiame darbe buvo ištirtos pelės širdies nervinio rezginio topografinės bei struktūrinės ypatybės totaliuose (nesupjaustytuose ir nesukarpytuose) širdies preparatuose, panaudojant histocheminį acetilcholinesterazės metodą, taip pat imunohistochemiškai ištirtos pelės širdies adrenerginės (simpatinės), cholinerginės (parasimpatinės) bei peptiderginės (sensorinės) nervinės struktūros. Rezultatai rodo, kad nežiūrint individualaus epikardinio rezginio variabilumo rūšies viduje, suaugusios pelės ir žmogaus intrakardinė nervinė sistema yra daug kuo panaši. Pelės širdyje yra cholinerginių, adrenerginių ir peptiderginių nervinių skaidulų. Dauguma pelės intrakardinių nervų ir nervinių pluoštų yra mišrūs, tačiau yra nervų, kuriuose yra tik cholinerginiai arba tik adrenerginiai aksonai. Šio neuroanatominio darbo rezultatai sudaro realias prielaidas tobulinti esamus ir kurti naujus širdies ritmo sutrikimų mechanizmų bei jų gydymo fiziologinių eksperimentų modelius, kurių dėka... [toliau žr. visą tekstą]
84

Intrinsische Innervation im Pansen von Wiederkäuern verschiedener Ernährungstypen

Münnich, Juliane 15 April 2009 (has links) (PDF)
Wiederkäuer können entsprechend ihrer Ernährungsgewohnheiten in Rauhfutterfresser, Konzentrat-selektierer und Intermediärtypen eingeteilt werden (HOFMANN 1989). Diese verschiedenen Ernährungstypen spiegeln sich in anatomischen Unterschieden des gesamten Gastrointestinaltraktes, insbesondere jedoch in der Vormagenanatomie wider. Ziel der vorliegenden Arbeit war es, die intrinsische Innervation des Pansens von Wiederkäuern des Rauhfutterfresser- und Intermediärtyps näher zu charakterisieren und mögliche Unterschiede zwischen diesen beiden Ernährungstypen aufzuzeigen. Dafür wurden im ersten Teil der Arbeit die Expression des generellen Neuronenmarkers HuC/D, der Syntheseenzyme Stickstoffmonoxidsynthase (NOS) und Cholinazetyltransferase (ChAT), sowie der Neuropeptide und der neuronalen Marker Neuropeptid Y (NPY), Vasoaktives Intestinales Peptid (VIP), Somatostatin (SOM) und Calbindin (Calb) an Häutchenpräparaten (whole mounts) des myenterischen Plexus aus dem Pansen der Rauhfutterfresser Schaf und Rind und der Intermediärtypen Ziege und Damwild immunhistochemisch untersucht. Desweiteren wurden die Parameter Gangliengröße (Neurone/Ganglion), Gangliendichte (Ganglien/cm² Plexusfläche) und Neuronendichte (Neurone/cm² Plexusfläche) der genannten Spezies tierartlich vergleichend erfasst. Beim Rind fanden sich mit 73±6 Neuronen/Ganglion (Mittelwert ± Standardabweichung) signifikant größere Ganglien als bei den kleinen Wiederkäuern Ziege (57±19), Damwild (51±20) und Schaf (45±18). Demgegenüber war die mittlere Gangliendichte beim Rind mit 6±1 Ganglien/cm² Plexusfläche signifikant geringer als bei Schaf (8±2) und Ziege (10±3), die wiederum eine signifikant geringere Gangliendichte als das Damwild mit 15±3 Ganglien/cm² Plexusfläche aufwiesen. Die Neuronendichte war im ventralen Pansensack von Damwild und Ziege (664±194 bzw. 584±295 Neuronen/cm² Plexusfläche) signifikant höher als beim Schaf (289±132). Die Neuronendichte des Rindes lag mit 432±238 Neuronen/cm² Plexusfläche zwischen den Werten der anderen Spezies. Alle untersuchten myenterischen Neurone waren entweder cholinerg oder nitrerg kodiert. Der relative Anteil nitrerger Neurone pro Ganglion war bei der Ziege (44±10 %) signifikant höher als beim Schaf (30±8 %). Dementsprechend war der relative Anteil cholinerger Neurone beim Schaf signifikant höher als bei der Ziege. Neben den Anteilen unterschied sich auch die Verteilung der nitrergen Neurone in den myenterischen Ganglien. Bei Rind und Ziege waren diese in Clustern am Rand der Ganglien angeordnet, während sie bei Schaf und Damwild locker über die Ganglienfläche verteilt erschienen. Mit Hilfe von Kolokalisationsuntersuchungen konnten bei allen untersuchten Spezies folgende Hauptneuronenpopulationen nachgewiesen werden: ChAT/SP>NOS/NPY/VIP>>ChAT/- und NOS/NPY. Dabei war die cholinerge Hauptpopulation ChAT/SP beim Schaf mit 67±7 % aller myenterischen Neurone signifikant stärker ausgeprägt als beim Damwild (58±11 %), während die nitrerge Hauptpopulation NOS/NPY/VIP bei der Ziege mit 40±9 % signifikant stärker als beim Schaf (26±6 %) ausgeprägt war. SOM und Calbindin fanden sich nur in einer sehr geringen Anzahl (vornehmlich cholinerger) Neurone, wobei SOM–positive Somata nur bei Damwild und Schaf nachgewiesen werden konnten. Im myenterischen Plexus von Rind und Ziege fanden sich ausschließlich Somatostatin-positive Nervenfasern. Im zweiten Teil der Arbeit wurden die Reaktionen von Zirkulärmuskelstreifen aus dem ventralen Pansensack von Schaf und Ziege auf Elektrische Feldstimulation nach Zugabe von Atropin bzw. L-NAME (NG-Nitro-L-Arginine Methylester Hydrochlorid), sowie die Reaktionen auf steigende Konzentrationen von Carbachol funktionell untersucht. Bei beiden Spezies führte Atropin zu verminderten, L-NAME zu verstärkten Kontraktionen als Reaktion auf Elektrische Feldstimulationen. Der muskarinerge Agonist Carbachol führte im Schaf- und Ziegenpansen zu einer konzentrationsabhängigen Steigerung der Motilität. Die Ergebnisse der neurochemischen Untersuchungen lassen auf eine stärkere cholinerge (und somit exzitatorische Kontrolle) des Pansens des Rauhfutterfressers Schaf im Vergleich zu Ziege und Damwild (Intermediärtypen) schließen. Die mikrobielle Fermentation grob strukturierten Rauhfutters erfordert starke, mixende Pansenkontraktionen. Es ist zu vermuten, dass ein höherer Anteil cholinerger myenterischer Neurone auch stärkere Pansenkontraktionen ermöglicht. Somit wäre die starke Ausprägung der cholinergen Innervation im Pansen des Rauhfutterfressers Schaf als eine Anpassung an die physikomechanischen Eigenschaften der bevorzugten Nahrungsquelle Gras zu sehen. Allerdings gelang es in der vorliegenden Arbeit nicht, diese Hypothese durch Unterschiede der in-vitro Motilität an ovinen und caprinen Pansenmuskelstreifen zu untermauern. In scheinbarem Widerspruch zu dieser Hypothese stand auch die nur gering ausgeprägte cholinerge Dominanz bei dem untersuchten großen Rauhfutterfresser Rind. Allerdings könnte diese genetisch bedingt sein, da es sich bei den untersuchten Proben um Material von auf hohe Milchleistung (und damit Konzentratverdaulichkeit) gezüchteten Rinderrassen handelte. Auch ein direkter diätetischer Einfluss auf die intrinsische Panseninnervation scheint in diesem Zusammenhang denkbar. Diese Annahme gründet sich auf Untersuchungen an kleinen Labornagern, bei denen die Aufnahme hoher Energiemengen zu einem Verlust enterischer cholinerger Neurone – und somit zu einem relativ höheren Anteil nitrerger Neurone führt. Deshalb sollte bei allen untersuchten Spezies neben einem möglichen genetischen Einfluss auch der Einfluss der Fütterung nicht außer Acht gelassen werden. Klarheit könnte hier neben vergleichenden Untersuchungen an Extensiv- und Hochleistungsrinderrassen auch die Untersuchung des Einflusses von bestimmten Fütterungsregimen auf die enterische Panseninnervation bringen.
85

Influência da atividade física sobre o envelhecimento inicial do plexo mioentérico do jejuno em rato Wistar / Influence of the physical activity on the initial aging of myenteric plexus of jejunum in Wistar rat

Naianne Kelly Clebis 24 March 2006 (has links)
Embora diversos trabalhos relatem as alterações fisiológicas que ocorrem no trato gastrointestinal com a senescência e com o exercício físico, poucos são os relatos morfológicos a respeito destas duas variantes. Portanto, o objetivo deste trabalho foi verificar qual a influência da atividade física (corrida em esteira) na ultraestrutura, na densidade neuronal (neurônios/mm2) e na área do perfil do corpo celular (µm2) dos neurônios mioentéricos do jejuno de ratos com a idade. Para tanto, foram utilizados 45 ratos Wistar divididos em três grupos: C (controle com seis meses), S (sedentário com 12 meses) e T (treinado com 12 meses) sendo utilizado 5 animais para cada técnica/grupo. Os preparados de membrana do jejuno foram corados com as técnicas histoquímicas de NADH e NADPH para estimar o número de neurônios e a área do perfil neuronal. Os resultados alcançados nos testes de esforço (TEMs) forçam sempre maiores no grupo T do que no grupo S. O peso dos animais do grupo T foi menor que os do grupo S. A área do jejuno-íleo foi mensurada e não presentou diferença significativa (P>0,05) entre os animais dos grupos C, S e T. Com exceção da membrana basal que apresentou-se menos definida e da região periganglionar que encontrava-se mais espassada nos animais do grupo S, não foram identificadas alterações ultraestruturais e no arranjo do plexo mioentéricos entre os grupos. A densidade dos neurônios reativos a NADH-diaforase foi menor (P<0,05) nos animais do grupo S (67,76±3,7) em relação aos animais dos grupos C (104,8±5,86) e T (95,18±7,18). Para os neurônios NADPH-diaforase, observou-se menor densidade neuronal nos grupos S (32,32±1,7) e T (27,39±1,2) comparado com o grupo C (44,53±4,5), mas diferenças significativas não foram evidencias entre os grupos S e T. A área do perfil do corpo celular (µm2) dos neurônios NADH- diaforase positivos diminuiu no grupo S (103,4±8,68) e aumento no grupo T (198,4±8,22) em relação ao grupo C (167±6,93). A área neuronal mensurada nos neurônios NADPH-diaforase positivos foi estatisticamente menor entre os grupos T (129,9±9,55) e C (186,8±9,34), mas não foram observadas diferenças entre estes grupos com o grupo S (157,3±3,64). Contudo, as alterações observadas indicam poucas são as influências do envelhecimento em animais com 12 meses de idade. / Although several works tell the physiologic alterations that they happen in the treatment gastrointestinal with the aging and with the physical exercise, few are the morphologic reports regarding these two variants. Therefore, the objective of this work was to verify which the influence of the physical activity (treadmill workout) in the ultrastructural, in the in the neuronal density (neurons/mm2) and in the profile area of the cellular body (µm2) of the myenteric neurons of the jejunum of rats with aging. For so much, 45 Wistar rats were used and they were divided in three groups: C (controls with six months), S (sedentary with 12 months) and T (trained with 12 months) being used 5 animals for each technique/group. The whole mounts of the jejunum were stained with the NADH and NADPH histochemistry techniques to estimate the density and the profile area of the myenteric neurons. The results of the maximal exercise test (METs) they always bigger in the T group than S group. The weight of the animals of the T group was smaller than S group. The jejunum-ileum area was measured and it didn\'t present significant difference (P>0.05) among the animals of the C, s and T groups. Except for the basal membrane that it came less defined and of the periganglionic area that was more scattered in the animals of the S group, they were not identified ultrastructural alterations and in the arrangement of the myenteric plexus among the groups. The density of the NADH-diaphorase neurons was smaller (P<0.05) in the animals of the S group (67.76±3.7) in relation to the animals of the C (104.8±5.86) and T (95.18±7.18) groups. For the NADPH- diaphorase neurons, smaller neuronal density was observed in the S (32.32±1.7) and T (27.39±1.2) groups compared with the C group (44.53±4.5), but the significant differentiate didn\'t evidence among the S and T groups. The profile area (µm2) of the NADH-diaphorase neurons decreased in the S group (103.4±8.68) and increase in the T group (198.4±8.22) in relation to the C group (167±6.93). The profile area of the NADPH-diaphorase neurons was smaller statically among the T (129.9±9.55) and C (186.8±9.34) groups, but differences were not observed among these groups with the S group (157.3±3.64). However, the observed alterations indicate little are the influences of the aging in animals with 12 months age.
86

Caraterização morfoquantitativa do plexo mioentérico do esôfago no modelo de distrofia muscular camundongo MDX / Morphoquantitative features of myenteric plexus of the oesophagus in MDX mice

Valquiria Barboza Mariotti 17 December 2012 (has links)
A Distrofia Muscular de Duchenne (DMD) é um tipo de miopatia grave, degenerativa e progressiva, geneticamente determinada e ligada ao cromossomo X. Além dos graves distúrbios cardiorrespiratórios e da motricidade, o paciente apresenta disfunções do sistema digestório, caracterizadas pelas desordens da motilidade. Entretanto, sabe-se que tais disfunções não ocorrem no camundongo MDX. O objetivo deste estudo foi estimar a densidade numérica por área da população total de neurônios (QA[T]) e dos neurônios nitrérgicos (QA[N]); assim como a área de secção transversal média do corpo celular destes neurônios (A[T] e A[N]) do plexo mioentérico esofágico e a largura média das fibras estriadas (L) das camadas musculares. Foram utilizados 40 camundongos machos da linhagem C57BL/10 nas idades de 4 e 10 semanas, distribuídos entre grupos experimentais (MDX4 e MDX10), e controles (C4 e C10). As estimativas foram analisadas em preparados de membrana dos esôfagos, e técnicas histoquímicas de NADH-diaforase (NADH-d) e NADPH-diaforase (NADPH-d) foram utilizadas para evidenciar toda a população de neurônios e os neurônios nitrérgicos, respectivamente. Os resultados mostraram que a QA[T] foi significativamente maior no grupo MDX10 em relação ao C10 (p<0.05); enquanto a QA[N] foi menor no grupo MDX4 em relação ao C4 (p<0.05). A A[T] foi menor no grupo MDX10 em relação ao MDX4 e ao C10 (p<0.05); enquanto que para a A[N] não houve diferença significativa entre os grupos controle e experimental, e tampouco entre os grupos de 4 e de 10 semanas. A variável L foi maior nos grupos MDX4 e MDX10 em relação aos seus respectivos controles de mesma idade (p<0.05). Concluímos que no plexo mioentérico esofágico de camundongos MDX existe uma redução dos neurônios mediadores do relaxamento, especialmente em animais jovens (MDX4), provavelmente porque o organismo tenta manter íntegra a função peristáltica do órgão. Esse fato pode explicar a adaptação e ausência de disfunções esofágicas durante quase toda a vida desses animais. / Duchenne Muscular Dystrophy (DMD) is the most common and the most severe muscular dystrophy of childhood. DMD is degenerative, progressive and a genetic X-linked disease. Besides the cardiomyopathy and the movement disorders, the patients have serious disfunctions in the alimentary system, characterized by motility disorders. However, it is known that such changes do not exist in MDX mice. The aim of this study was to estimate the neuronal numerical density/area of total (QA[T]) and nitregic neurons (QA[N]), the average cross-sectional area of total (A[T]) and nitregic (A[N]) neurons in myenteric plexus of the oesophagus and the average width of striped muscle of muscular layer (L). Forty C57BL/10 male mice were studied from four to ten weeks of age, divided into four groups: MDX mice formed the experimental groups (MDX4 and MDX10) and C57BL/10 male mice without the mutation formed the control groups (C4 and MDX10). Whole mounts preparations were obtained from the samples and histochemistry for NADH-diaphorase (NADH-d) and NADPH-diaphorase (NADPH-d) were used for morphometric evaluation. The results showed a significant increase of the QA[T] in the MDX10 than C10 (p<0.05), and a decrease of the QA[N] in MDX4 comparing to C4 (p<0.05). The A[T] decreased significantly in MDX10 comparing to both MDX4 and C10 (p<0.05), while no significant differences were observed among all the groups regarding the A[N]. The groups MDX4 and MDX10 showed a significant increase in L when compared to its controls at the same age (p<0.05). We conclude that in the myenteric plexus of the oesophagus in MDX mice there is a reduction of the inhibitory neurons, manly in the young animals (MDX4), probably to keep normal the peristaltic functions. Thus, it may explain the adaptation and the absence of oesophageal disfunction during almost the whole life in this animal model.
87

Efeitos da ração autoclavada sobre os aspectos quantitativos e morfométricos dos neurônios mioentéricos do jejuno de ratos em períodos de pré e pós-desmame / Effects of the autoclaved diets in the quantitative and morphometric aspects of rat’s jejunum myenteric neurons in pre and pos weaning

Patrícia Orlandini Gonçalez 17 December 2004 (has links)
Para evitar a presença de microorganismos nas rações fornecidas para animais de laboratório, são utilizados processos de esterilização como a autoclavagem, porém esta ocasiona perda de nutrientes, como as proteínas, devido à alta temperatura usada. A deficiência protéica pode afetar a atividade celular, provocando diferentes alterações nos tecidos. Por estes fatos, objetivou-se avaliar a ação da ração autoclavada sobre os neurônios do plexo mioentérico do jejuno de ratos em período de crescimento. Para tanto, foram utilizados ratos em período dedesmame (21 dias) provindos de mães que receberam ração autoclavada ou não autoclavadadurante a gestação e lactação e ratos em período de pós-desmame (21 a 70 dias) alimentados com o mesmo tipo de dieta que as mães recebiam. Para a mensuração do perfil do corpo celular e contagem do número de neurônios por área, estes foram evidenciados pelo método de nadh-diaforase. O peso corpóreo dos animais não apresentou diferença significativa em relação ao tipo de alimentação (p > 0,05). Houve uma diminuição do comprimento jejuno-íleo em ratos alimentados com ração autoclavada (p > 0,05). O número de neurônios por área aumentou aproximadamente 10% para ratos que receberam ração autoclavada (p > 0,05). Já a área do perfil dos corpos dos neurônios apresentou um aumento para ratos alimentados com ração autoclavada, sendo este significativo para animais em período de desmame. Todos os fatores observados apresentaram diferença significativa em relação às idades / Autoclaving is the most common sterilization process to avoid the presence of pathogens in the diet of laboratory animals. However, it may cause the loss of nutrients such as proteins due to the high temperature used. The protein deficiency can affect cellular activity, leading todifferent changes in the tissues. Due to these facts, this research aimed to verify the effect of autoclaved diet in the jejunum neurons of the myenteric plexus in rats during their growing phase. The experiment groups were constituted by rats in weaning period (21 days) from mothers that received autoclaved or not diets during the gestation and lactation, and rats in post weaning period (21 to 70 days) fed the same diet the mothers received. In order to measure the neurons body profile and to quantify the number of neurons by area, they were stained by the nadh-diaphorase method. No significant changes were observed to the weight body in animals with autoclaved diet (p > 0.05). There was a decrease in the length of jejunum-ileum in rats treated with autoclaved diet (p > 0.05). The number of neurons by area increased approximately 10% in the rats supplied with autoclaved diet (p > 0.05). The neuron body profile area increased in the rats that received autoclaved diet and it was significant in the animals in weaning period. Nevertheless, all factors observed showed significant differences when related to animal age
88

Aspectos estruturais, ultraestruturais e quantitativos dos efeitos da desnutrição protéica pré e pós-natal e da renutrição pós-natal no plexo ganglionar da traquéia de ratos. / Structural, ultrastructural and quantitative aspects from pre and postnatal protein deprivation and postnatal refeeding effects on ganglioned trachea plexus of the rats.

Thiago Habacuque Silva de Souza 27 January 2011 (has links)
A desnutrição é responsável pela metade das 11 milhões de crianças abaixo de 5 anos de idade que falecem todo ano. A desnutrição é fator determinante para instalação de doenças do sistema respiratório e nervoso. Avaliaram-se os efeitos da desnutrição e renutrição no plexo traqueal de ratos. Foram utilizados filhotes dos grupos: nutridos (N) (20% de caseína), desnutridos (D) (5% de caseína) e renutridos (R) (alimentados com 5% de caseína até 21 dias e com 20% até os 42 dias). Os espécimes foram avaliados pela NADH-d; NADPH-d; AChE; SP; VIP e MEV. Observou-se fraca reatividade à AChE dos neurônios do grupo D. Não houve diferença do número de neurônios e gânglios (NADH-d e NADPH-d). A área neuronal foi maior no grupo N (NADH-d e NADPH-d.) Os gânglios do grupo N eram maiores (NADH-d) e sem diferença entre gânglios reativos à NADPH-d. Na metade torácica da traquéia havia cerca de 80% dos neurônios e gânglios (NADH-d e NADPH-d). A desnutrição protéica alterou componentes do plexo traqueal e a renutrição foi responsável pela recuperação parcial deste desenvolvimento. / Malnutrition is responsible for half of the 11 million children under age 5 who die every year. Malnutrition is a determining factor for plant diseases of the respiratory system and nervous. We assessed the effects of malnutrition and renutrition tracheal plexus of rats. We used offspring of the groups: nourished (N) (20% casein), undernourished (UN) (5% casein) and renourish (R) (fed 5% casein up to 21 days and 20% up to 42 days ). The specimens were evaluated by NADH-d, NADPH-d, AChE, SP, VIP and SEM. There was a weak reactivity to AChE neurons of group UN. There was no difference in the number of neurons and ganglia (NADH-d and NADPH-d). The neuronal area was higher in group N (NADH-d and NADPH-d). Ganglia were higher in group N (NADH-d) and no difference between the ganglia reactive to NADPH-d. In half of the thoracic trachea was about 80% of neurons and ganglia (NADH-d and NADPH-d). Protein malnutrition altered components of the tracheal plexus and renutrition was responsible for the partial recovery of this development.
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Densidade e área do perfil celular dos neurônios mioentéricos reativos a acetilcolinesterase, NADH e NADPH-diaforase positivos do ceco de ratos (Rattus norvergicus) adultos / Density and area of the cellular outline of the myoenteric plexus reactive to Acethylcholinesterase, NADH and NADPH diaphorase positives of the caecum of adult (Rattus norvergicus) rats

Carlos Eduardo Seyfert 16 December 2003 (has links)
Tendo seu início no íleo terminal onde se abre a papila ileal, o ceco é a porção inicial do intestino grosso onde ocorre parte da digestão da celulose proveniente da alimentação e a posterior absorção de seus produtos. O ceco de rato é uma estrutura sacciforme que apresenta partes distintas, tanto macroscópica quanto estruturalmente. O presente estudo teve como finalidade avaliar a densidade e a área do perfil celular dos neurônios mioentéricos em diferentes regiões do ceco de ratos adultos com sete meses de idade (384gr), utilizando as técnicas da Acetilcolinesterase, NADH e NADPH-diaforase. Para tanto o ceco foi dividido em quatro regiões: uma, próxima à ampola cecal (PA), uma, apical mesentérica (AM), uma, basal antimesentérica (BA) e outra apical antimesentérica (AA). Observou-se, que, no que diz respeito à densidade neuronal, existe diferença significativa para as regiões estudadas, sendo à região PA a que apresentou maior quantidade de neurônios com todas as técnicas utilizadas. Em média, nos 80 campos (17,92mm2) microscópicos contados, foram encontrados 1479 ± 357 neurônios acetilcolinesterásicos positivos, 717 ± 142 neurônios que se coram pela técnica da NADH-d e 240 ± 26 células nervosas que se coram pela técnica da NADPH-d. Com relação ao perfil celular dos neurônios, o teste de variância mostrou não haver diferença significativa entre as regiões. O menor e o maior perfil celular foi observado junto à região BA, em neurônios corados com as técnicas da AChE e NADPH-d respectivamente, tendo o menor perfil, 77,94&micro;m2 e o maior, 1579,64&micro;m2. Conforme a área do perfil celular, os neurônios foram agrupados em três classes: pequenos, médios e grandes. A classe mais freqüente em todos as regiões estudadas para as três técnicas foi a dos neurônios médios, chegando a 72,4% corados pela técnica da AChE junto à região AA, 68% na região PA para a técnica da NADH-d e 77,6% com a técnica da NADPH-d na região PA. Concluiu-se que, existe diferença regional na distribuição dos neurônios da parede do ceco do rato. / Beginning in the terminal ileum where the ileal papilla opens, the caecum is the initial portion of the large intestine, where part of the digestion of the cellulose coming from the food and the absorption of its products take place. This study had the purpose of evaluating the density and the cell profile area of the myoenteric neurons in different regions of the caecum of adult rats aging seven months (384 g body weight), using the techniques of acetylcholinesterase (AChE), NADH- and NADPH-diaphorase. For that, the caecum was divided into four regions: next to the caecal ampulla (PA), apical mesenteric (AM), basal antimesenteric (BA) and apical antimesenteric (AA). It was observed that, in what concerns the neuronal density, there is a significant difference for the regions studied, the PA region exhibiting the greatest amount of neurons with all the techniques employed. On average, in the 80 microscopic fields (17.92 m2) counted, 1,479 ± 357 neurons were found with AChE, 717 ± 142 with NADH-d and 240 ± 26 with NADPH-d. As for the cell profile of the neurons, the Variance Analysis showed that there is not a significant difference among the regions. The smallest and the largest cellular profiles were observed at the BA region with the techniques of AChE and NADPH-d, respectively, the smallest having 77.94 &micro;m2 and the largest 1,579.64 &micro;m2. According to the area of the cell profile, the neurons were grouped in three classes: small, medium and large. The most frequent class in all the regions studied and techniques employed was that of medium neurons, reaching 72.4% with AChE at the AA region, 68% in the PA region with NADH-d and 77.6% with NADPH-d in the PA region. Therefore, it was verified that there is a regional difference in the distribution of the neurons in the wall of the rat caecum.
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Características estruturais e estereológicas  do plexo cardíaco de camundongos expostos à poluição ambiental / Stereological and Structural characteristics of the cardiac plexus in mice exposed to environmental air pollution

Karina do Valle Marques 25 May 2012 (has links)
Os objetivos do presente trabalho foram determinar a morfologia do plexo cardíaco e verificar se o coração de camundongos é alterado pela exposição à poluição atmosférica em relação ao peso, ao número de neurônios e gânglios. Camundongos foram mantidos em câmaras situadas próximas a vias de trafego intenso em São Paulo. Os animais foram divididos em 4 grupos (n=5) segundo a exposição à poluição atmosférica no período gestacional e/ou pós natal: ar filtrado (F-F), ar não filtrado (NF-NF), ar filtrado e ar não filtrado (F-NF) e ar não filtrado e ar filtrado (NF-F). Ao atingirem 120 dias de vida, os animais foram eutanasiados e seus corações removidos. O número de neurônios cardíacos assim como seu volume, volume do gânglio, área do neurônio, perímetro e o diâmetro de Feret máximo (FMax) e mínimo (FMin) foram estimados por meio de avaliações morfométricas e estereológicas. Os neurônios e gânglios cardíacos foram corados pelo método de Giemsa. As fibras colágenas foram identificadas pelo método de Picro-sirius sob luz polarizada. Verificou-se que as fibras colágenas tipo III são predominantes na cápsula do gânglio nos grupos NF-F e NF-NF. O peso corpóreo foi significativamente menor nos animais que foram expostos no período pós natal (F-NF, NF-NF) quando comparados aos grupos F-F e NF-F. A média do perímetro neuronal foi maior no grupo F-F que nos grupos expostos no período gestacional e pós natal (F-NF, NF-F e NF-NF). O FMax foi estatisticamente diferente entre o grupos expostos no período pós natal (F-NF e NF-NF) (p<0,05). Houve uma redução significativa no volume dos neurônios nos grupos F-NF e NF-NF. Os resultados permitem especular que a mudanças no controle autonômico do coração resultante da exposição à poluição atmosférica, pode ser relacionado a alterações no desenvolvimento do plexo cardíaco / The aims of the present study were to determine the cardiac plexus morphology and to test whether or not the heart of the mice alters in weight, neuronal and ganglia number with air pollution exposure. Mice were maintained in exposure chambers situated close to a busy crossroads in São Paulo. Animals were grouped in to four groups (n=5) according to prenatal and/or postnatal exposure to air pollution: filtered air (F-F); non-filtered air (NFNF); filtered and non-filtered air (F-NF); non-filtered and filtered air (NF-F). Reaching 120 days of life, the animals were euthanized for obtaining their hearts. The number of cardiac neurons as well as their volume, ganglion volume, neuron sectional area, perimeter and maximum (FMax) and minimum (FMin) Ferrets diameter were estimated under the stereological and morphometric aspects. The cardiac neurons and ganglia were stained employing the Giemsa method. Collagen fibers were identified by Picro-sirius under polarized light. Type III collagen fibers predominate in the ganglion capsule of the NF-F and NF-NF groups. Body weight was significantly reduced in those animals exposed to air pollution postnatally (F-NF, NF-NF) when compared to groups F-F and NF-F. The average of the neuronal perimeter was larger in F-F group than in those groups with gestational and postnatal exposure (F-NF, NF-F and NF-NF). The volume, volume do gânglio, área do neurônio, perímetro e o diâmetro de Feret máximo FMax was statistically different among the groups exposed to air pollution postnatally (F-NF and NF-NF) (p<0.05). A decrease in the total neuronal volume was significantly detected in F-NF and NF-F groups. The mean neuron volume was significant in the F-NF and NF-NF. Our results, allow us to speculate that changes in autonomic control of heart resulting from exposure to air pollution may be linked to alterations in the development of the cardiac plexus

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