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Implicações da variabilidade genética de Trichogramma pretiosum Riley, 1879 no seu desempenho como agente de controle biológico / Genetic variability of Trichogramma pretiosum Riley, 1879, in its role as a biological control agentAloisio Coelho Junior 06 July 2015 (has links)
O conhecimento das implicações da variabilidade genética em populações de inimigos naturais, principalmente parasitoides, é de vital importância para a otimização de programas de controle biológico. Desta forma, o presente trabalho teve por objetivo determinar como a variabilidade genética influencia diferentes parâmetros biológicos de Trichogramma pretiosum Riley, 1879 em experimentos de laboratório e de campo. Para que este objetivo fosse atingido, foram avaliados: 1) o efeito da seleção de isolinhagens de T. pretiosum em condições de laboratório, marcadas por meio do DNA mitocondrial, no subsequente desempenho de campo; 2) como a UR afeta a capacidade de voo de isolinhagens, marcadas por meio do DNA mitocondrial, de espécimes de T. pretiosum oriundas do Brasil e EUA; 3) a compatibilidade reprodutiva entre isolinhagens norteamericanas e brasileira de T. pretiosum, avaliada por meio de uma abordagem integrativa e 4) o possível estabelecimento de uma linhagem de T. pretiosum proveniente da Colômbia num novo ecossistema, no Nordeste brasileiro. Com base nos resultados do presente trabalho conclui-se que a variabilidade genética de T. pretiosum exerce grande influência em parâmetros biológicos do parasitoide, uma vez que: 1) os diferentes desempenhos reprodutivos das isolinhagens em condições de laboratório foram correspondentes àqueles em condições de campo, sendo as sequências mitocondriais uma técnica de marcação precisa e eficiente para avaliação do desempenho de T. pretiosum em condições de campo; 2) para algumas isolinhagens, as condições ambientais do local onde se pretende liberar T. pretiosum, se distintas do hábitat natural do parasitoide, podem afetar negativamente o voo deste inseto; 3) foi registrada incompatibilidade reprodutiva leve e diferenças morfológicas mais pronunciadas entre as isolinhagens americanas e brasileira, geneticamente variáveis; 4) foram observados fortes indícios de que uma linhagem de T. pretiosum, introduzida em Petrolina, PE há 22 anos, trazida de Palmira, Colômbia, se estabeleceu naquela região. / The knowledge on genetic variability in populations of natural enemies, especially parasitoids, has a vital importance for the optimization of biological control programs. Thus, this study aimed to determine the influences of genetic variability on different biological parameters of Trichogramma pretiosum Riley, 1879, in laboratory and field experiments. We evaluated: 1) the effect of selection of T. pretiosum isofemale strains in laboratory conditions, marked by mitochondrial DNA, on the subsequent field performance; 2) the effects of RH on flight capacity isofemale lines, marked by the mitochondrial DNA, of T. pretiosum specimens from Brazil and the USA; 3) the reproductive compatibility between USA and Brazilian isofemale lines of T. pretiosum, through an integrative approach, and 4) the possible establishment of a T. pretiosum strain from Colombia in a new ecosystem in the Brazilian Northeast. The results allow to conclude that genetic variability of T. pretiosum has great influence on biological parameters of the parasitoid, since: 1) the different reproductive performance of isofemale strains in laboratory conditions corresponded to those under field conditions, and mitochondrial DNA was accurate and efficient, marking technique for the evaluation of T. pretiosum performance in field conditions; 2) for some isofemale lines, the environmental conditions of the release sites, if distinct from the natural habitat of the parasitoid, may adversely affect flight capacity of the parasitoid; 3) slight reproductive incompatibility and more pronounced morphological differences were observed between American and Brazilian isofemale lines, genetically variable; 4) there is strong evidence that T. pretiosum line introduced in Petrolina, PE, 22 years ago, brought from Palmira, Colombia, has established in that region.
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O efeito do sistema intra-uterino de levonorgestrel (SIU-LNG) no fluxo das artérias uterinas, volume uterino e espessura endometrial em pacientes com endometriose pélvica: estudo comparativo com o análogo de GNRH (GnRHa) / The effect of System Intrauterine levonorgestrel (LNG-IUS) in the uterine artery flow, volume uterinoe Endometrial thickness in patients with endometriosis Pelvic: comparative study with the GnRH analogue (GnRHa)Luiz Alberto Manetta 13 December 2007 (has links)
Objetivos: O objetivo deste estudo foi comparar os índices de Pulsatilidade (IP) e Resistência (IR) das artérias uterinas, o volume uterino e a espessura endometrial após o uso do Sistema Intra-uterino de Levonorgestrel (SIU-LNG) ou do agonista do GnRHa (GnRHa) em pacientes portadoras de endometriose pélvica. Pacientes e métodos: Setenta e nove mulheres voluntárias, com idade entre 18 e 40 anos, foram incluídas neste ensaio clínico comparativo, prospectivo, randomizado e controlado. Dezoito foram eliminadas do estudo baseadas nos critérios de exclusão, As 61 pacientes remanescentes foram divididas em dois grupos: 31 pacientes fizeram parte do grupo SIU-LNG (uma foi excluída antes da inserção por apresentar-se grávida) e 30 fizeram parte do grupo GnRHa. Foram submetidasa exame ultra-sonográfico transvaginal bidimensional no dia em que iniciaram o tratamento (inserção do SIU-LNG ou administração de uma ampola de 3,75 mg de GnRHa por via intra-muscular) e seis meses após, avaliando a espessura endometrial, o volume uterino e os IR e IP das artérias uterinas. Resultados: Ambos tratamentos promoveram redução da espessura endometrial (6.08±3.00mm para 2.70±0.98mm e 6.96±3.82mm para 3.23±2.32mm - média ±SD, grupo SIU-LNG e grupo GnRHa, respectivamente). O volume uterino teve redução no grupo usuário do GnRHa (86.67±28.38cm3 para 55.27±25.52cm3) sem alteração significativa nas usuárias do SIU-LNG (75.77±20.88cm3 para 75.97±26.62cm3). Em relação à ascularização uterina, notamos incremento dos IP das artérias uterinas em ambos os grupos (grupo SIU-LNG: artéria uterina direita de 2.38±0.72 para 2.76±0.99 (média ±SD) e artéria uterina esquerda 2.46±0.70 para 2.87±0.96, e grupo GnRHa: artéria uterina direita 2.04±0.59 para 3.12±0.98 eartéria uterina esquerda 2.24±0.59 para 3.15±0.89). Em relação ao IR das artérias uterinas, observamos incremento no grupo GnRHa em ambas artérias e somente na artéria uterina esquerda no grupo SIU-LNG (grupoSIU-LNG - artéria uterina direita de 0.85±0.08 para 0.88±0.07 e artéria uterina esquerda de 0.86±0.07 para 0.89±0.06, e grupo GnRHa: artéria uterina direita de 0.81±0.07 para 0.93±0.09 e artéria uterina esquerda 0.84±0.06 para 0.93±0.09). No entanto, ao compararmos as diferenças, a elevação foi significativamente maior nas usuárias do GnRHa. Conclusões: Ambos GnRHa e SIU-LNG promoveram redução na espessura endometrial e aumento no IP das artérias uterinas. Houve redução do volume uterino nas usuárias do grupo GnRHa, não se alterando no grupo SIU-LNG. Em relação ao IR, houve incremento em ambas as artérias nas usuárias de GnRHa e somente na artéria uterina esquerda nas usuárias do SIU-LNG. / Objectives:The objective of the present study was to compare the uterine arteries pulsatility index (PI) and resistence index (IR), uterine volume and endometrial thickness changes promoted by the use of the levonorgestrel intrauterine device (LNG-IUD) and the gonadotropin-releasing hormone analogue (GnRHa)in patients with endometriosis. Methods: Seventy nine women aged 18 to 40 years were included in this randomized controlled trial. Eighteen was excluded based on the exclusion criteria. The patients were randomly allocated in two groups: 31 women who used the LNG-IUD (since one became pregnant before insertion and wasexcluded) and 30 who used monthly GnRHa injections. They were submitted to a transvaginal two dimensional ultrasound scan on the day the treatment started and 6 months later, for the evaluation of uterine arteries PI, uterine arteries RI, uterine volume and endometrial thickness. Results: The use of LNG-IUD promoted an ndometrial thickness decrease (6.08±3.00mm to 2.7±0.98mm; mean±SD) as does the use of GnRHa (6.96±3.82mm to 3.23±2.32mm). The uterine volume decreased in the GnRHa group (86.67±28.38cm3to 55.27±25.52cm3), but not in the LNG-IUD group (75.77±20.88cm3 to 75.97±26.62cm3). Uterine arteries PI increased in both groups : Uterine arteries PI: LNG-IUD right uterine arterie 2.38 ± 0.72 to 2.76 ± 0.99 and left uterine arterie 2.46 ± 0.70 to 2.87 ± 0.96, and GnRHa right uterine arterie 2.04 ± 0.59 to 3.12 ± 0.98 and left uterine arterie 2.24±0.59 to 3.15 ± 0.89. Uterine arteries RI increased in both arteries in GnRHa and only in the left uterine arterie in the LNG-IUD :Uterine arteries RI : LNG-IUD right uterine arterie 0.85 ± 0..08 to 0.88 ± 0.07 and left uterine arterie 0.86 ± 0.07 to 0.89 ± 0.06, and GnRHa right uterine arterie 0.81 ± 0.07 to 0.93 ± 0.09 and left uterine arterie 0.84 ± 0.06 to 0.93 ± 0.09 . However, the increase was significant higher in the GnRHa group. Conclusions: Both GnRHa and LNG-IUD promoted an endometrial thickness decrease and an increase in the uterine arteries PI. The uterine volume decreased in women who used GnRHa, but not in those who used LNG-IUD.
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Characterization of signaling mechanisms regulating cardiac contractilityKubin, A.-M. (Anna-Maria) 17 May 2011 (has links)
Abstract
The heart adapts to hemodynamic overload with cardiac hypertrophy. Initially the increase in heart mass normalizes wall stress and permits normal cardiac function. In the long term pathological growth is associated with increased heart size, loss of functional myocytes and fibrotic replacement, heart dilatation and cardiac dysfunction, which can ultimately lead to heart failure.
Vasoactive peptides participate in the regulation of cardiac contractility in an auto/paracrine way, but the peptidergic signaling pathways are largely unknown. The present study aimed to characterize the signaling mechanisms mediating the positive inotropic effect of endothelin-1 (ET-1) and the effects of prolactin releasing peptide (PrRP) on cardiac contractility in the isolated perfused rat heart preparation.
The study demonstrated that mitogen-activated protein kinases (MAPK) have opposing roles in the regulation of cardiac contractility stimulated by ET-1. Extracellular signal-regulated kinase 1/2 (ERK1/2) mediated positive inotropic response to ET-1 was found to be counterbalanced by p38-MAPK. In addition, the effect of ET-1 was partly dependent on enhanced NADPH oxidase reactive oxygen species (ROS) generation, which activated the ERK1/2 pathway. In contrast, β-adrenergic inotropic effect was limited by stimulation of ROS production via negating phospholamban phosphorylation. The positive inotropic effect of ET-1 was counterbalanced by guanylyl cyclase (GC)-cGMP-protein kinase G (PKG) pathway and neuronal nitric oxide synthase (nNOS). PrRP was found to exert a direct positive inotropic effect which was independent of cAMP and was suppressed by concurrent activation of protein kinase Cα (PKCα) and protein phosphatase 1 (PP1), and dephosphorylation of phospholamban.
In conclusion, in the present study signaling pathways in the acute regulation of cardiac contractility stimulated by ET-1 were characterized. The results suggest that the positive inotropic effect of ET-1 is mediated by ROS and ERK1/2 while p38-MAPK counterbalances the effect of ET-1. In addition, GC-cGMP-PKG pathway and nNOS modulate the response to ET-1. The study also established the previously unknown cardiac effects of PrRP. The findings provide a better understanding of molecular mechanisms involved in the regulation of cardiac contractility, and may indicate potential targets for novel therapeutic interventions. / Tiivistelmä
Sydänlihaksen lisääntynyt mekaaninen kuormitus esimerkiksi verenpainetaudin tai sydäninfarktin yhteydessä voi johtaa sydämen kammion seinämän paksuuntumiseen eli hypertrofiaan. Hypertrofia auttaa sydäntä sopeutumaan lisääntyneeseen työmäärään, mutta se on myös sydän- ja verisuonitautitapahtumien riskitekijä. Pitkään jatkuva kuormitus johtaa usein sydämen pumppausvoiman heikkenemiseen ja sydämen vajaatoimintaan.
Sydän tuottaa useita paikallisesti vaikuttavia vasoaktiivisia tekijöitä, jotka osallistuvat sydämen supistuvuuden säätelyyn. Väitöskirjatutkimuksessa tutkittiin signaalinvälitysjärjestelmiä, jotka osallistuvat endoteliini-1:n (ET-1) sydämen supistusvoimaa lisäävän eli positiivisen inotrooppisen vaikutuksen muodostumiseen sekä selvitettiin prolaktiinia vapauttavan peptidin (PrRP) vaikutuksia sydämen supistusvoimaan käyttämällä koemallina eristettyä, perfusoitua rotan sydäntä.
Väitöskirjatyön tutkimustulokset osoittivat, että mitogeeni-aktivoituvat proteiinikinaasit (MAPK) ERK1/2 ja p38-MAPK osallistuvat ET-1:n inotrooppisen vaikutuksen säätelyyn. ERK1/2 välitti, ja p38-MAPK rajoitti ET-1:n lisäämää supistusvoiman kasvua. NADPH-oksidaasin tuottamat reaktiiviset happiradikaalit välittivät sydämessä ET-1:n inotrooppista vaikutusta ja ERK1/2 fosforylaatiota. Toisaalta NADPH-oksidaasin tuottamat happiradikaalit rajoittivat β-adrenergisen agonistin inotrooppista vaikutusta. Guanylaattisyklaasi (GC)-cGMP-proteiinikinaasi G (PKG) -järjestelmä ja neuronaalinen typpioksidisyntaasi (nNOS) vaimensivat ET-1:n lisäämää sydämen supistusvoiman kasvua. PrRP lisäsi sydämen inotropiaa syklisestä AMP:stä riippumattomalla tavalla, mutta vasteen säätelyyn havaittiin osallistuvan proteiinikinaasi C ja proteiinifosfataasi 1.
Väitöskirjatutkimuksessa saatiin uutta tietoa solunsisäisistä viestinvälitysjärjestelmistä, jotka osallistuvat sydämen supistusvoimaan säätelyyn. Havaintojen perusteella ET-1:n positiivisen inotrooppisen vaikutuksen muodostumista välittävät reaktiiviset happiradikaalit ja ERK1/2, kun taas p38-MAPK rajoittaa vastetta. Lisäksi GC-cGMP-PKG -järjestelmä ja nNOS osallistuvat ET-1:n vaikutusten säätelyyn. Tutkimuksessa havaittiin myös, että PrRP vaikuttaa sydämen supistuvuuteen. Solutason mekanismien yksityiskohtien tunteminen voi mahdollistaa tulevaisuudessa sydän- ja verisuonisairauksien, kuten sydämen hypertrofian ja vajaatoiminnan, hoitomenetelmien tehostumisen ja mahdollisesti uudentyyppisten hoitomenetelmien kehittämisen.
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Uso da imunocastração como alternativa à castração cirúrgica na produção de novilhos para abate / Use of immunocastration as an alternative to surgical castration in the production of steers for slaughterMachado, Diego Soares 25 February 2015 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The objective of this study was to evaluate the use of immunological castration as an alternative to surgical castration in the production of beef cattle. In the research were used 48 Aberdeen Angus male bovines, monitored from initial age of six months and initial average weight of 160 kg at weaning. The animals were randomly distributed in the following treatments: surgically castrated at birth; surgically castrated at weaning; immunocastrated Bopriva® with three doses of vaccine, and immunocastrated Bopriva® with four doses of vaccine. The experimental design used was the completely randomized, with 12 replications. Means were classified by F test and compared by Tukey test with α=.05. There was interaction between date of sampling and treatment for serum testosterone levels in the blood plasma, however at slaughter all steers kept only residual levels of testosterone, characterized as castrated. Steers immunocastrated with three applications of Bopriva® had higher daily weight gain and total weight gain in the finishing phase, in relation to surgically castrated at weaning. However, throughout the evaluation stages, the performance was similar between treatments (P>.05). Steers castrated at birth had higher fat thickness to when adjusted 100 kg of cold carcass and lower chilling loss than castrated immunologically with three doses (P<.05). Immunocastration with three doses of Bopriva® provided increment in muscle participation in relation to surgically ones at both ages, and muscle: bone ratio in relation to castrated at weaning. It also reduced the participation of fat in relation to castrated at birth. Total internal organs in percentage of empty body weight, differ between the two immunocastration protocols, with superiority when applied four doses (3.61 vs 3.39 kg). Steers surgically castrated at birth showed superiority in the sum of sum of internal, toilet and kidney fats, for immunocastrated with three doses, regardless of the way it was expressed. The immunological castration proved to be a viable alternative to surgical castration, not changing the main parameters of economic interest and meat quality attributes, and promotes animal welfare, eliminating the surgery. / O objetivo deste estudo foi avaliar a utilização da castração imunológica, como alternativa a castração cirúrgica na produção de bovinos de corte. Na pesquisa foram utilizados 48 bovinos machos, da raça Aberdeen Angus, monitorados a partir de idade inicial de seis meses e peso médio incial de 160 kg, por ocasião do desmame. Os animais foram distribuídos aleatoriamente nos seguintes tratamentos: castrados cirurgicamente ao nascer; castrados cirurgicamente a desmama; imunocastrados com três doses da vacina Bopriva® e imunocastrados com quatro doses da vacina Bopriva®. O delineamento experimental utilizado foi o inteiramente casualizado, com 12 repetições por tratamento. As médias foram classificadas pelo teste F e comparadas pelo teste de Tukey, com α=0,05. Houve interação entre data de amostragem e tratamento sobre os níveis séricos de testosterona no plasma sanguíneo, todavia na ocasião do abate todos os novilhos mantinham apenas níveis residuais de testosterona, caracterizando-se como castrados. Novilhos imunocastrados com três aplicações de Bopriva® apresentaram maior ganho de peso diário e ganho de peso total, na fase de terminação, que castrados cirurgicamente ao desmame. Entretanto em toda a fase de avaliação o desempenho foi similar entre os tratamentos (P>0,05). Novilhos castrados cirurgicamente ao nascimento apresentaram maior espessura de gordura subcutânea, ajustada para 100 kg de carcaça fria e menor quebra ao resfriamento que castrados imunologicamente com três doses (P<0,05). A imunocastração com três doses proporcionou incremento na participação de músculo em relação aos castrados cirurgicamente nas duas idades, e na relação músculo:osso em relação aos castrados ao desmame, mas reduziu a participação de gordura em relação aos castrados ao nascimento. O total de órgãos internos expressos em percentual do peso de corpo vazio diferiu entre os dois protocolos de imunocastração, com superioridade quando aplicou-se quatro doses (3,61 vs 3,39 kg). Novilhos castrados cirurgicamente ao nascimento apresentaram superioridade no somatório das gorduras internas, de descarte e renal, em relação a imunocastrados com três doses, independente da forma como foi expressa. A castração imunológica mostrou-se como uma alternativa viável em relação à castração cirúrgica, não alterando os principais parâmetros de interesse econômico e atributos de qualidade da carne, além de promover o bem-estar animal, eliminando a intervenção cirúrgica.
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Estresse por derrota social intermitente em ratos Wistar machos : revisão e modulação farmacológica experimental do sistema CRFVasconcelos, Mailton França de January 2018 (has links)
O neuropeptídeo/hormônio CRF integra respostas de estresse a nível endócrino, imunológico e comportamental dos mamíferos. A atividade neuronal CRFérgica inapropriada pode estar por trás do aparecimento de sintomas associados a transtornos neuropsiquiátricos. Os experimentos apresentados nesta tese descrevem a modulação farmacológica de ligantes de CRF que compõem o sistema CRFérgico em ratos Wistar machos submetidos ao protocolo de estresse por derrota social. A experiência de episódios intermitentes à derrota social prejudicou o comportamento de interação social. Microinjeções de antagonista da proteína ligante de CRF e antagonista (CRF6-33) e antagonista específico do receptor de CRF do tipo 1 (CP316311) no núcleo intersticial da estria terminal, separadamente, restauraram a aproximação social em animais estressados. Esses achados sugerem que o conteúdo de CRF no núcleo intersticial da estria terminal está envolvido na modulação de respostas relacionadas à ansiedade induzidas pelo estresse social. / The CRF neuropeptide/hormone integrates endocrine, immune and behavioral stress responses of mammals. Inappropriate CRFergic neuronal activity may underlie the appearance of symptoms associated with neuropsychiatric disorders. The experiments presented in this dissertation describe the pharmacological modulation of CRF ligands composing the CRFergic system in male Wistar rats submitted to the social defeat stress protocol. The experience of intermittent episodes of social defeat disrupted behaviors of social interaction. Microinjections of an antagonist of CRF binding protein (CRF6-33) and specific antagonist of CRF receptor type 1 (CP316311) in the bed nucleus of stria terminalis, separately, restored the social approach behavior in stressed animals. These findings suggest that the CRF content in the bed nucleus of stria terminalis is involved in the modulation of anxiety-related responses induced by social stress.
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Abundant expression of the membrane-anchored protease-regulator RECK in the anterior pituitary gland and its implication in the growth hormone/insulin-like growth factor 1 axis in mice / 細胞膜アンカー型プロテアーゼ制御因子RECKのマウス下垂体前葉における豊富な発現と成長ホルモン/インスリン様成長因子系における役割Ogawa, Shuichiro 27 July 2020 (has links)
京都大学 / 0048 / 新制・論文博士 / 博士(医学) / 乙第13362号 / 論医博第2204号 / 新制||医||1045(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 稲垣 暢也, 教授 渡邉 大, 教授 影山 龍一郎 / 学位規則第4条第2項該当 / Doctor of Medical Science / Kyoto University / DFAM
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Response of preterm infants with transient hypothyroxinaemia of prematurity to the thyrotropin-releasing hormone stimulation test is characterized by a delayed decrease in thyroid-stimulating hormone after the peak / 一過性低サイロキシン血症を呈した極低出生体重児ではTRH負荷試験においてピーク後の遅延反応を認めるYamamoto, Akane 23 March 2021 (has links)
京都大学 / 新制・課程博士 / 博士(医学) / 甲第23078号 / 医博第4705号 / 新制||医||1049(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 稲垣 暢也, 教授 万代 昌紀, 教授 小杉 眞司 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
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Srovnání tří metod použitých při vyhodnocení schopnosti šíření semen a jejího významu pro kolonizaci opuštěných polí u druhů z čeledi Asteraceae / Comparison of three trials used for assassement of ability to disperse by wind and its importance for colonazition of abandoned fields in Asteraceae speciesVlasta, Tomáš January 2017 (has links)
Several methods are used for studying seed dispersal (seed traps, tracking individual seeds, tracking seeds coloured by fluorescent colours, etc.) However, only a few studies compared results obtained by several methods. In first part of this master thesis, I compared the three above mentioned methods used for studying seed dispersal using species from Asteraceae family. From previous research within the study area (Úštěcko), it is known that dry grassland species are able to colonize abandoned fields. Using seed dispersal data obtained within this theses, I tried to assess the role of seed dispersal on distribution of dry grassland species on abandoned fields both on local and regional scale. The results showed that dispersal curves obtained by the three methods differ significantly. This results may be due to different wind conditions during the experiments. Seed trap data show results from long-term seed dispersal influenced by highly variable wind conditions. In contrary, seed release experiments showed results based on single dispersal event under limited wind conditions. Tracking seeds coloured by fluorescent colours was shown to be not convenient for small seeds, but I can recommend this method for larger seeds. Influence of seed dispersal ability on abundance of dry grassland species on...
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Úloha stabilních analogů peptidu uvolňujícího prolaktin při obezitě a hypertenzi. / The role of stable analogs of prolactin-releasing peptide in obesity and hypertension.Neprašová, Barbora January 2018 (has links)
Anorexigenic neuropeptides have the potential to decrease food intake and ameliorate obesity and its complications such as high blood glucose or high blood pressure. However, they are not able to cross the blood-brain barrier after peripheral application. Recently, we have designed and synthesized lipidized analogs of prolactin-releasing peptide (PrRP), which resulted in stabilization of the molecule and allowed us to apply the peptide to the periphery to achieve its central biological effect, as it was demonstrated by increased neuronal activity shown by c-Fos in particular hypothalamus nuclei. The aim of this study was to choose the effective dose in acute food intake experiments and then to characterize the subchronic effect of palmitoylated PrRP analogs in mouse and rat models of obesity and diabetes. Several animal models were used: diet-induced obese (DIO) mice (C57Bl/6J), DIO Sprague-Dawley rats, and two rat models with leptin receptor-deficiency: Zucker diabetic (ZDF) rats and spontaneously hypertensive (SHROB) rats. Consumption of a high-fat diet in DIO mice and rats increased their body weight and blood pressure. Two-week intraperitoneal treatment with palmitoylated PrRP31 lowered the food intake, body weight, and returned the blood pressure to normal levels. This treatment also improved...
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Neuroprotective Effect Of Thyrotropin-Releasing Hormone (TRH) Against Glutamate Toxicity In VitroYard, Michael 13 November 2009 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Acute and chronic activation of both ionotropic and metabotropic glutamate (glut) receptors is implicated in many neurodegenerative disorders including AD, dementia, epilepsy, stroke and neurotrauma. TRH and glut receptors (ionotropic & metabotropic) receptors are differentially coexpressed in granule and pyramidal neurons of the hippocampus. The author shows TRH to be protective when added to cultured pituitary adenoma (GH-3) cells and neuron-like pheochromocytoma (PC12) cells either prior to, during, or after glut-induced toxicity (Endo. Soc. Abs. 01), and also shows that the possible neuroprotective mechanism may involve heterologous downregulation of the metabotropic glut receptors, using superfused hippocampal slices and noting a reduction of Gαq/11 (SFN Abs. 02). He has also demonstrated that TRH protected against glut toxicity in fetal cortical cultures (Endo. Soc. Abs. 04). To extend these studies he used 14-day cultured rat fetal hippocampal neurons (Day E17) to determine if TRH is protective against toxicity induced by specific ionotropic and metabotropic glut agonists. Neuronal viability and integrity were assessed by trypan blue exclusion and LDH release after 18 hrs following 30 min exposure to glut agonists. Ten µM dihydroxyphenylglycine (DHPG, a Group 1 receptor agonist) + 30 µM N-methyl-D-aspartate (NMDA)-induced toxicity (42% vs contr. P<0.05); whereas, concurrent and continued treatment with 10 uM but not 1uM 3Me-HTRH resulted in less neuronal death and damage (86% vs contr P<0.05; 53% vs contr. P>0.05) respectively. DHPG treatment alone (10 µM) for 30 min. was non-toxic by both criteria (90% vs contr. P<0.05). The data suggest that TRH may be a selective modulator of glut-induced toxicity.
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