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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.
11

The effect of protein-energy malnutrition on reactive gliosis following global ischemia

Harmon, Monique Iona 03 December 2007
Protein-energy malnutrition (PEM) has been found in up to 16.3% of acute stroke patients upon admission to hospital. Our laboratory has previously shown that PEM impairs functional outcome in a gerbil model of global ischemia, but the mechanism has not been established. The purpose of the current study was to characterize the marked reactive gliosis apparent in a subset of these animals that could represent an increased inflammatory response. A second objective was to validate a screening protocol for assessing completeness of ischemia in this model. Male Mongolian gerbils, aged 11-12 weeks, were randomized to PEM (2% protein) or control diet (12.5% protein) for 28d. PEM animals lost 12.2% of their initial body weight, and feed intake and serum albumin concentration were 12.3% and 17.8% lower than controls, respectively. At day 28, animals underwent 5 min bilateral common carotid artery occlusion (ischemia) or sham surgery. Activity was monitored using infrared beam interruptions for 20h post-surgery to screen for complete ischemia on the basis of persistent hyperactivity. Brain sections were stained with hematoxylin & eosin, and viable hippocampal CA1 neurons were counted at 10d post-ischemia. Immunohistochemistry for glial-fibrillary acidic protein (GFAP) and ricinus communis agglutinin -120 (RCA-120), markers for astrocytes and microglia, respectively, and the inflammatory cytokine TNF-alpha was performed on brain sections at 6h, 24h, 3d and 10d post-surgery (Ischemic, n=8; Sham, n=3). The activity monitoring procedure for detecting complete ischemia validated against hippocampal CA1 neuronal loss at 10d demonstrated an accuracy of 84.6%. Temporal changes in GFAP and RCA-120 immunoreactivity characteristic of reactive gliosis were demonstrated following ischemia, but this was not exacerbated by PEM. TNF-alpha immunoreactivity following ischemia was also unaltered by PEM. Ischemia significantly reduced surviving CA1 neurons at 10 days post-ischemia (two-way ANOVA; p<0.05), but this was not influenced by PEM. Impaired functional outcome in PEM animals following global ischemia can not be accounted for by increased hippocampal CA1 neuron death or by altered glial response.
12

Effects of protein-energy malnutrition on outcome from global cerebral ischemia

Prosser-Loose, Erin Jane 27 September 2010 (has links)
The goal of my thesis was to elucidate the impact of protein-energy malnutrition (PEM, a condition commonly found in aging stroke patients) on outcomes from global ischemia. I first examined the hypothesis that PEM will impair working memory in the adult gerbil as measured in the T-maze. Gerbils were fed an adequate (12.5%) or low protein (2%; PEM) diet for 6wk. Stringent assessment of T-maze performance indicated an improvement with PEM although I was unable to reconcile whether this was increased motivation for the food reward or enhanced working memory.<p> The second hypothesis tested was PEM will decrease expression of plasticity-associated hippocampal mRNA and protein expression following global ischemia in the gerbil. The plasticity markers brain-derived neurotrophic factor (BDNF), tropomyosin-related kinase B (trkB), and growth-associated protein-43 (GAP-43) were examined in the CA1 hippocampal region post-ischemia. PEM induced in gerbils for 4wk did not alter the global ischemia-induced decrease in CA1 neurons. Ischemia resulted in increased CA1 pyramidal expression of BDNF and trkB mRNA at 1, 3, and 7d post-ischemia and increased trkB protein expression at 3 and 7d. PEM further elevated the increased trkB protein detected at 7d in the fibres. Ischemia resulted in increased GAP-43 protein at 3 and 7d post-ischemia with PEM increasing this expression at 3d in the CA3 and hilar regions in addition to CA1. These findings suggest an increased stress-response and/or hyperexcitability state in the hippocampus of malnourished ischemic animals.<p> Since the reliability of the gerbil model of global ischemia has come into question, the third part of my thesis tested the hypothesis that the influence of pre-existing PEM on global ischemia-induced hippocampal injury can be reliably studied with the 2-vessel occlusion rat model. The impact of PEM on CA1 neuronal death and dendritic damage was examined. Rats received protein adequate (18%) or deficient (2%; PEM) diet for 7-8d prior to global ischemia. PEM did not worsen the decrease in CA1 neurons and dendrites observed at 7d post-ischemia. Importantly, I found that PEM altered blood glucose and acid-base balance during surgery and caused brief hypothermia post-surgically, factors which are important for consistent brain injury.<p> Taken together, these findings reveal (i) that nutritional care, although frequently ignored, can have robust effects on recovery mechanisms after brain ischemia; and (ii) the challenges of studying pre-existing PEM in an established rodent model of stroke.
13

The effect of protein-energy malnutrition on reactive gliosis following global ischemia

Harmon, Monique Iona 03 December 2007 (has links)
Protein-energy malnutrition (PEM) has been found in up to 16.3% of acute stroke patients upon admission to hospital. Our laboratory has previously shown that PEM impairs functional outcome in a gerbil model of global ischemia, but the mechanism has not been established. The purpose of the current study was to characterize the marked reactive gliosis apparent in a subset of these animals that could represent an increased inflammatory response. A second objective was to validate a screening protocol for assessing completeness of ischemia in this model. Male Mongolian gerbils, aged 11-12 weeks, were randomized to PEM (2% protein) or control diet (12.5% protein) for 28d. PEM animals lost 12.2% of their initial body weight, and feed intake and serum albumin concentration were 12.3% and 17.8% lower than controls, respectively. At day 28, animals underwent 5 min bilateral common carotid artery occlusion (ischemia) or sham surgery. Activity was monitored using infrared beam interruptions for 20h post-surgery to screen for complete ischemia on the basis of persistent hyperactivity. Brain sections were stained with hematoxylin & eosin, and viable hippocampal CA1 neurons were counted at 10d post-ischemia. Immunohistochemistry for glial-fibrillary acidic protein (GFAP) and ricinus communis agglutinin -120 (RCA-120), markers for astrocytes and microglia, respectively, and the inflammatory cytokine TNF-alpha was performed on brain sections at 6h, 24h, 3d and 10d post-surgery (Ischemic, n=8; Sham, n=3). The activity monitoring procedure for detecting complete ischemia validated against hippocampal CA1 neuronal loss at 10d demonstrated an accuracy of 84.6%. Temporal changes in GFAP and RCA-120 immunoreactivity characteristic of reactive gliosis were demonstrated following ischemia, but this was not exacerbated by PEM. TNF-alpha immunoreactivity following ischemia was also unaltered by PEM. Ischemia significantly reduced surviving CA1 neurons at 10 days post-ischemia (two-way ANOVA; p<0.05), but this was not influenced by PEM. Impaired functional outcome in PEM animals following global ischemia can not be accounted for by increased hippocampal CA1 neuron death or by altered glial response.
14

Effect of post-ischemic caloric restriction on cell death and functional recovery

McEwen, Barbara Rae 21 September 2009 (has links)
Since caloric restriction (CR) can modify multiple pathways central to the ischemic cascade and enhance neuroplasticity mechanisms, we hypothesized that CR should exert protective effects following brain ischemia. Previous studies have suggested benefit when CR was administered prior to ischemia. This study investigated whether prolonged CR beginning after global ischemia would result in lasting protection as assessed by performance in the open field, as a measure of functional outcome, and hippocampal CA1 neuronal counts. Adult male Mongolian gerbils were subjected to five minute bilateral carotid artery occlusion (I) or sham surgery (S) with tympanic temperature maintained at 36.5 ± 0.2ºC during the intra-ischemic period. After screening out gerbils with incomplete ischemia, each of the two surgical groups were randomly assigned to control diet (CON) or 30% CR for the duration of the study (60d). Gerbils were tested in the open field on d3, 7, 10, 30 and 60. Ischemic animals on control diet showed a significantly higher level of activity in the open field (impaired habituation) compared to SCON gerbils on all test days (p<0.001). Open field activity was decreased 9% in the ICR group versus ICON gerbils on d7 (p=0.024), suggesting a transient neuroprotective effect. Open field activity of the SCR gerbils began increasing relative to that of SCON gerbils during the last 30 days of the study (p=0.055 on d60), raising the question of suitability of the open field test for long-term studies of CR and ischemia. Brain sections obtained at d60 were stained with hematoxylin & eosin. Hippocampal CA1 neuron counts were reduced 88% by ischemia (p<0.001), and there was no sparing effect of CR. These findings suggest that prolonged CR administered beginning after global ischemia cannot diminish brain injury or enhance long-term recovery.
15

Variações regionais e efeitos da castração nos lobos dorsal e ventral da próstata do gerbilo da Mongólia (Meriones unguiculatus) /

Rochel, Sabrina Santos. January 2006 (has links)
Resumo: No presente estudo foram propostas duas análises a respeito do complexo prostático do gerbilo Meriones unguiculatus. A primeira consistiu em examinar, com uso de técnicas de microdissecção, microscopia de luz e microscopia eletrônica de varredura, a estrutura anatômica e histológica dos lobos prostáticos, bem como caracterizar as suas possíveis diferenças regionais. Os resultados mostram que o complexo prostático de gerbilos normais, ao contrário do descrito em trabalhos anteriores, apresenta quatro pares de lobos distintos: ventrais, dorsais, dorsolaterais e anteriores ou glândulas coaguladoras. Com exceção da glândula coaguladora, estes lobos diferem quanto ao grau de ramificação e dimensões das unidades túbuloacinares, aspecto da secreção e organização estromal. Todos, porém, apresentam, além dos ductos principais, três regiões histologicamente distintas e designadas de acordo com a localização em relação à uretra. A segunda proposta consistiu em avaliar comparativamente o efeito progressivo da castração cirúrgica entre os lobos ventrais e dorsais, com ênfase para as alterações em alguns componentes estromais, como as células musculares lisas, fibras colágenas e os proteoglicanos de condroitim sulfato. Em conclusão, tanto as características estruturais como a resposta à falta de andrógenos apontam para diferenças marcantes intra e interlobulares no complexo prostático do gerbilo, as quais devem ser consideradas em estudos experimentais. / Abstract: In this study, two analyses about the prostatic complex of the gerbil Meriones unguiculatus were suggested. The first one consisted in examine, using microdissection techniques, light and scanning electron microscopies, the anatomical and histological structure of the prostatic lobes, and to characterize its possible regional differences. The results show that the prostatic complex of normal gerbils, in contrast of previously described, presents four pairs of distinct lobes: ventral, dorsal, dorsolateral and anterior or coagulating gland. Except for the coagulating gland, these lobes differ on the ramification degree and tubuloacinar units dimension, secretion aspect and stromal organization. All of them, however, present, besides the principal ducts, three histologically distinct regions, named according to the localization in relation to the urethra. The second proposal of the work consisted in evaluate comparatively the progressive effect of castration between the ventral and dorsal lobes, with emphasis to the alterations in some stromal components, such as smooth muscle cells, collagen fibers and condroitin sulphate proteoglycans. In conclusion, both structural characteristics and the answer to the lack of androgen points to remarkable inter and intralobular differences of the gerbil prostatic complex, which must be considered in experimental studies. / Orientador: Rejane Maira Góes / Coorientador: Patrícia Simone Leite Vilamaior / Banca: Classius de Oliveira / Banca: Marcelo Martinez / Mestre
16

Neonatal testosterone treatment affects the paw elevation of the Mongolian gerbil (Meriones unguiculatus)

Robertson, Rohan 08 1900 (has links)
<p> The present thesis reports an experiment that investigated the phenomenon of asymmetric paw elevation in the tripedal stance of the Mongolian gerbil, and tested the Geschwind-Galaburda extra-genetic theory of human handedness. Neonate gerbils of both sexes were injected with testosterone propionate during the "critical" period of brain development. They were then assessed for asymmetry in eye opening, for anogenital distance, and for paw elevation and scent marking before and after puberty. Eye opening asymmetry was not affected by treatment. Paw elevation was affected by treatment, with treated gerbils of both sexes displaying more right elevations before and after puberty than untreated gerbils. Control females displayed systematic patterns in paw elevation before and after puberty. Adult gerbils in all conditions displayed more consistency in paw elevation than young gerbils. Anogenital distance was increased with treatment, but only in the females. Adult scent marking behavior was marginally reduced with treatment, but only in the males. Results are interpreted within the Geschwind-Galaburda theory of handedness, and the hormonal basis of paw elevation is discussed. </p> / Thesis / Master of Science (MSc)
17

The Effects of Naturally Occurring Plant Products on Experimental Haemonchus contortus Infection in Gerbils and Sheep

Squires, Jill Marie 08 June 2009 (has links)
Haemonchus contortus is a blood-sucking abomasal helminth of small ruminants responsible for major economic losses to producers worldwide. Widespread resistance to commercial anthelmintics has created a need for alternative methods of parasite control. One method involves using plant products with natural anthelmintic properties. This thesis assessed the efficacy of several plant products against experimental Haemonchus contortus infection in gerbils and sheep. In gerbil assays, animals were orally infected with 600 third-stage Haemonchus larvae and treated once or daily for 5 days with artemisinin, Artemisia annua aqueous or ethanolic extract, an orange oil emulsion, or Asimina triloba ethanolic extract. Nine days post-infection, gerbils were euthanized, their stomachs removed, and the worms counted. Significant anthelmintic activity was not found for artemisinin, A. annua extracts, or A. triloba extract. The orange oil product caused significant parasite reductions up to 87.8% when administered for 5 days. The orange oil emulsion was tested in sheep to evaluate the product against Haemonchus in its natural host. Sheep were orally inoculated with 10,000 Haemonchus larvae and, one month later, dosed with the emulsion once or daily for 3 days. Fecal egg counts were monitored daily starting on the first day of dosing and continuing to 14 days post-dosing. Results showed that a single dose of the product caused highly significant fecal egg count reduction (97.4%) compared to control sheep and that there is no advantage to treating for 3 days. Thus, the orange oil emulsion shows promise as an alternative to commercial dewormers. / Master of Science
18

Desenvolvimento da próstata masculina e feminina do gerbilo da Mongólia submetido à exposição no período embriofetal e pós-natal de etinilestradiol / Development of male and female prostate of the Mongolian gerbil submitted to the exposure embryofetal period and postnatal ethinylestradiol

Perez, Ana Paula da Silva, 1984- 16 August 2018 (has links)
Orientador: Sebastião RobertoTaboga / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-16T22:39:47Z (GMT). No. of bitstreams: 1 Perez_AnaPauladaSilva_M.pdf: 6001319 bytes, checksum: e128a337509c2f2d797523dafdca8524 (MD5) Previous issue date: 2010 / Resumo: Nos machos, a morfogênese prostática é um evento comandado por andrógenos, que agem diretamente via fatores parácrinos secretados pelo mesênquima. Nas fêmeas, o desenvolvimento embriológico da próstata parece ocorrer em níveis baixos de hormônios esteróides, porém a presença desses hormônios no organismo adulto induz a diferenciação e atividade secretória das células prostáticas. A exposição precoce a estrógeno no período de desenvolvimento embrionário e neonatal tem sido relacionada a distúrbios permanentes na morfofisiologia de vários órgãos do sistema reprodutor de ambos os sexos. Estudos epidemiológicos indicam que homens expostos a componentes estrogênicos durante o desenvolvimento intra-uterino apresentam maior probabilidade de serem inférteis e de desenvolverem câncer de testículo e próstata, enquanto as mulheres tornam-se mais susceptíveis a desenvolver câncer de mama, útero e vagina. Porém, como a exposição precoce a hormônios esteróides é capaz de alterar permanentemente vários órgãos reprodutivos, torna-se questionável se esses agentes também podem interferir com a estrutura e fisiologia da próstata feminina. Com base nesses relatos, o objetivo deste trabalho foi verificar o comportamento da próstata ventral masculina e da próstata feminina de gerbilos adultos que foram expostos ao estrógeno sintético, etinilestradiol durante o desenvolvimento pré-natal, além de analisar a ação pós-natal de andrógenos exógenos sobre ambas as glândulas que foram submetidas à estrogenização do desenvolvimento. Para isso, foram realizadas as análises sorológicas para a quantificação dos hormônios esteróides e as próstatas de gerbilos machos e fêmeas adultos foram submetidas às análises morfológicas, morfométrico-estereológica e imunocitoquímica. Os resultados mostraram que a exposição intra-uterina ao etinilestradiol elevou os níveis séricos de estradiol em ambos os sexos durante a vida adulta, promovendo assim alterações na próstata ventral masculina como neoplasia intra-epitelial prostática (NIP) e irregularidades no epitélio prostático feminino, além de observar o aumento das fibras reticulares e colágenas em ambas as glândulas. A análise imunocitoquímica revelou aumento da imunorreatividade de ?-actina na camada muscular que envolve regiões de lesões prostáticas, e o aumento da imunorreatividade de receptores andrógenos (AR) nas próstatas de ambos os sexos. Os animais que sofreram estrogenização durante o desenvolvimento e mediante aplicação de testosterona na vida pós-natal tiveram os níveis de estradiol normalizado, ainda assim apresentaram lesões prostáticas. Várias dessas alterações são mediadas pelo ER? que foi constatado pela alta imunorreatividade nas próstatas tratadas de ambos os sexos. Com os dados percebeu-se que o tratamento realizado durante o período pré-natal com etinilestradiol promoveu alterações na próstata ventral masculina e na próstata feminina de gerbilos adultos. Porém essas alterações foram mais efetivas na próstata ventral masculina, estando estas associadas aos níveis anormais de estradiol observados nos machos adultos. / Abstract: In males, prostatic morphogenesis is an event controlled by androgens, which act directly via paracrine factors secreted by the mesenchyme. In females, the embryological development of the prostate appears to occur in environment low levels of steroid hormones, but the presence of these hormones in the adult life induces differentiation and secretory activity of prostatic cells. The early exposure to estrogen during the embryonic and neonatal development has been related to disturbances in the permanent morphophysiology of the reproductive system of both sexes. Epidemiological studies indicate that men exposed to estrogenic components during the pre natal development have a higher probability to be infertile and develop and testicular and prostate cancer, while women become more susceptible in developing breast, uterus and vagina cancer. However, as early exposure to steroid hormones can permanently alter various reproductive organs, it is questionable whether these agents can also interfere with the structure and physiology of the female prostate. Based on these reports, the aim of this study was to verify the behavior of gerbil ventral male and female prostates which were exposed to synthetic estrogen ethinylestradiol (EE) during embryonic development, as well as analyze the postnatal action of exogenous androgens on both glands that were submitted to estrogenization. For this were carried out serologic analysis for the measure of steroid hormones and prostate of male and female gerbils adults were subjected to analysis to morphological, morphometric-stereological and immunocytochemical analysis. The results showed that EE intrauterine exposure increased the estradiol serum levels in both sexes, thus promoting alterations in the male prostate such as prostatic intraepithelial neoplasia (PIN) and irregularities in the female prostatic epithelium. Additionally, it was observed an increase of reticular fibers and collagen in both glands. Immunocytochemical analysis revealed increased imunnoreactivity of ?-actin in the muscle layer surrounding regions of prostatic lesions, and increased imunnoreactivity of androgen receptor (AR) in both male and female prostates. The animals that suffered development estrogenization and with the application of testosterone in postnatal life had estradiol levels normalized, still presented prostatic lesions. In addition, in these animals it was verified an increase in the imunnoreactivity of estrogenic receptors (ER?). Several of these alterations are mediated by ER? was verified by high immunoreactivity in prostates treated in both sexes. With the data we noticed that the treatment performed during the prenatal period with ethinyl estradiol promoted alterations in male ventral prostate and female prostate of adult gerbils. But these changes were most effective in the male ventral prostate, these being associated with abnormal levels of estradiol observed in adult males. / Mestrado / Biologia Celular / Mestre em Biologia Celular e Estrutural
19

Repercussões histopatologicas na prostata ventral do gerbilo da Mongolia (Merinones unguiculatus) apos suplementação por hormonios esteroides

Scarano, Wellerson Rodrigo 21 July 2006 (has links)
Orientador: Sebastião Roberto Taboga / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-07T17:58:14Z (GMT). No. of bitstreams: 1 Scarano_WellersonRodrigo_D.pdf: 4897591 bytes, checksum: ce5fe2f21b6836d646532424d518315c (MD5) Previous issue date: 2006 / Resumo: O tecido prostático é susceptível aos desníveis hormonais provocados, principalmente pelo processo de envelhecimento. A hiperplasia benigna prostática e o câncer de próstata são doenças que acometem uma grande parcela da população masculina, e parecem estar envolvidas com alterações hormonais. Por isso, o esclarecimento dos processos celulares e teciduais envolvendo os hormônios sexuais: testosterona e estradiol são, sem dúvida, importantes para o entendimento da etiologia desses processos patológicos. O gerbilo (Meriones unguiculatus) foi utilizado como modelo experimental pois, segundo a literatura, é susceptível ao aparecimento de lesões autóctones e responde bem à carcinogênese experimental, mostrando-se um bom modelo experimental. Numa primeira etapa, foram utilizados animais de três idades diferentes: púbere, adulta e senil. Esses animais foram submetidos à suplementação androgênica e as próstatas ventrais foram destinadas a análises histopatológicas, quantitativas, imunocitoquímicas e ultraestruturais. Foi observado aumento no peso da glândula e também na altura das células epiteliais em todas as idades. Tal aumento reflete o aumento da capacidade sintética observada pela dilatação das organelas de síntese, às vezes de aspecto vesiculoso, ocupando toda a região supranuclear. Nos animais adultos e velhos foram notadas regiões hiperplásicas e displásicas freqüentemente associadas a Neoplasias Intraepiteliais de diferentes graus e a adenocarcinomas. Houve aumento na espessura da camada de células musculares lisas (CML) ao redor dos ácinos nos animais púberes e adultos, enquanto nos animais velhos houve diminuição dessa camada. Além disso, as CML se mostraram aparentemente hipertróficas e com maior atividade sintética nos animais púberes e adultos. Foi notado aparente aumento da vascularização periacinar, onde se observou a presença de freqüentes vasos sanguíneos em todas as idades após o tratamento. Ademais, em todas as idades foi observado aumento da densidade de marcação de receptores androgênicos após o tratamento, evidenciando a possível relação desses receptores com os efeitos observados. Em uma segunda etapa experimental, avaliou-se o efeito do estradiol sobre o tecido prostático intacto e hipoandrogênico em animais adultos, tentando com isso simular situações de descompensação hormonal, típicas da senilidade. As alterações epiteliais foram freqüentes nos animais tratados com estradiol onde se observou aumento na altura das células epiteliais, aparecimento de regiões de intensa displasia e hiperplasia, e a formação de PINs. Outro aspecto que independe da presença da testosterona é o arranjo dos elementos fibrilares e não fibrilares da matriz extracelular entre as CML, apontando para um possível papel dessas células no rearranjo e na síntese desses componentes após os tratamentos estrogênicos. Nos animais castrados observou-se acúmulo de elementos da matriz extracelular sob o epitélio e em animais intactos presença desses elementos dispersos e escassos. Em ambos os grupos: intactos e castrados, notou-se que as CML e os fibroblastos apresentam fenótipo secretor acentuado após o tratamento com estradiol. Houve aumento na densidade de marcação ERa e AR positivos em regiões de hiperplasia apontando para um possível papel desses receptores na formação de lesões pré-malígnas e malignas. Portando, conclui-se que o gerbilo é susceptível a ação da testosterona e do estradiol, os quais provocam desarranjos estruturais e ultraestruturais de cunho patológico e funcional, mostrando-se um ótimo modelo para o estudo das doenças prostáticas de etiologia hormonal / Abstract: Not informed. / Doutorado / Biologia Celular / Doutor em Biologia Celular e Estrutural
20

Nutritional influence on oxidative stress in global ischemia

Bobyn, Patricia Joan 31 October 2003
Primary brain injury in stroke is followed by oxidative stress and further neural damage. Glutathione (GSH) is critical in antioxidant defense. Since cysteine is limiting in GSH synthesis, Phase 1 of this study investigated the effect of a dietary sulphur amino acid deficiency (-SAA) on neural damage in global hemispheric hypoxia-ischemia (GHHI). Rats were fed a -SAA or control diet for 6 days, and subjected to GHHI after 3 days. Histologically evaluated neural damage at 7 days post hypoxia-ischemia was greater in -SAA rats. Brain GSH concentration was decreased in -SAA rats 3 days after ischemia. A cysteine precursor, L-2-oxothiazolidine-4-carboxylic acid (OTC) administered to -SAA rats did not ameliorate neural damage. GSH is decreased by protein-energy malnutrition (PEM) in some tissues. Phase 2 investigated the effect of PEM on brain oxidative stress, neural damage and behaviour after global ischemia in adult male gerbils. In a 2x2 factorial design, gerbils were fed an adequate protein (12%; C) or low protein (2%; PEM) diet for 4 weeks, then subjected to transient ischemia (I) or sham surgery (S). After 12 hours of reperfusion, brain from half the gerbils was collected for biochemical analyses. Remaining gerbils were fed pre-surgery diets for 10 more days. To assess functional consequences of ischemia, gerbils were placed in an open field on Days 3, 7 and 10 after surgery. On Day 10, viable hippocampal CA1 neurons were counted. C-I gerbils did not habituate as readily in the open field on day 3 as C-S, but normalized by day 7. PEM-I gerbils failed to habituate by day 10, traveled greater distance than other gerbils and 7 of 12 displayed thigmotaxis, a <i>wall-hugging</i> preference for the outer perimeter of the open field. CA1 neuron loss in I was 61.5% of S, but unaffected by PEM. Four of 12 PEM-I gerbils had marked increases in hippocampal glia. Hippocampus protein thiols were reduced by PEM and by ischemia, consistent with oxidative stress. GSH concentration, glutathione reductase activity and thiobarbituric acid reactive substances were not significantly affected by PEM or ischemia. Findings from these two studies suggest well-nourished but not nutritionally-deficient rodents tolerate a mild brain insult. This is clinically relevant because many elderly stroke victims suffer from PEM at the time of ischemia, which may compromise recovery.

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