Background and objective. Cardiovascular disease (CVD) is the most important life-threatening disease. The heart is densely innervated with sympathetic fibers, however prolonged sympathetic activation can damage the heart, resulting in chronic heart failure. Recent findings suggest that norepinephrine (NE) may contribute to cardiac fibrosis and a loss of cardiomyocytes due to apoptosis. Many studies demonstrate that NE is able to induce transforming growth factor-beta (TGF-beta), connective tissue growth factor (CTGF) and vascular endothelial cell growth factor (VEGF), which are two key mediators during the cardiac remodeling process. Nowadays most of the studies in cardiac remodeling are focusing on myocytes, whereas a few studies have been paid to the role of the cardiac fibroblasts (CF). In this thesis, the role of NE in cardiac fibrosis and apoptosis was investigated in CF. The mechanisms by which NE induced TGF-beta, CTGF and VEGF expression in CF were examined. Furthermore, the therapeutic potentials in cardiac fibrosis by blocking NE with adrenergic receptor antagonists were explored. / Conclusions. NE is a pathogenic molecule involving cardiac remodeling. NE exhibited its fibrotic and apoptotic effects on CF in a concentration-dependent mariner. Up-regulation of the TGF-P/CTGF pathway could be a critical mechanism of NE-induced cardiac fibrosis, while NE was capable of activating Bax-Capase 3 to cause CF apoptosis. The presence of CTGF/VEGF complex in CF in response to NE may contribute to the inhibition of angiogenesis, which may be other mechanism of ischemic heart injury. These findings indicate that an increase in NE production associated with over activation of sympathetic system is harmful to the heart and may be a major cause of chronic heart failure. Furthermore, the ability of adrenergic receptor antagonists to block NE-induced cardiac fibrosis suggest the therapeutic approach by using NE receptor antagonists for patients with chronic heart diseases. / Methods and results. Rat CF was isolated, characterized, and stimulated with NF (0.01 to 100 muM for 6 to 72h). Procollagens (I and III), TGF-beta1, bax, bclXL, CTGF and VEGF gene expressions were measured by real-time PCR method. Collagen protein level was measured by Sirius red-based colorimetric method and Western blot. CTGF protein level, VEGF concentration, cell viability, apoptosis caspase 3 activity was measured by Western blot, ELISA, MTT assay cytometry, and flurogenic assay kit, respectively. Results showed that NE at concentrations of 0.01 to 0.1 muM was capable of up-regulating procollagens, TGF-beta1 and CTGF expression (ail p<0.05). However, NE at higher concentrations (10 to 100 muM) significantly induced CF apoptosis (p<0.01). This was demonstrated by a significant increase in bax gene expression and caspase-3 activity, while inhibiting bclXL gene expression. At this higher concentration of NE, CTGF expression was inhibited, whereas VEGF expression was promoted. However, using immunoprecipitation, the CTGF/VEGF complex was found in CF in response to NE, thereby inhibiting angiogenesis such as tube formation in cultured endothelial cells. Interestingly, addition of NE receptor antagonists produced differential effects on procollagen expression and apoptosis. For example, carvedilol and doxazosin, the alpha-receptor-associated non-selective antagonists, were able to inhibit NE-stimulated procollagens expression, but this was not inhibited by specific beta-receptor antagonists, metoprolol and propranolol, suggesting that NE signals through the alpha-receptor to mediate cardiac fibrosis. Interestingly, all four types of adrenoceptor antagonists had no effect on NE-induced CF apoptosis, which suggests that NE induces CF apoptosis via a receptor-independent mechanism. / Lai, Ka Bik. / Adviser: Yu Cheuk Man. / Source: Dissertation Abstracts International, Volume: 70-06, Section: B, page: 3419. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (leaves 160-199). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.

Recent approaches in depression therapeutics include triple reuptake inhibitors, drugs that target three monoamine systems. Using in vivo electrophysiological and microdialysis techniques, the effects of 2- and 14-day treatments of escitalopram, nomifensine and the co-administration of these two drugs (TRI) were examined in male Sprague-Dawley rats. Short- and long-term TRI administration decreased NE firing and had no effect on DA neurons. Normal 5-HT firing rates were maintained after 2-day TRI administration compared to the robust inhibitory action of selective serotonin reuptake inhibitors (SSRIs). Escitalopram treatment enhanced the tonic activation of the 5-HT1A receptors given the increase in firing observed following WAY100635 administration. Nomifensine treatment enhanced tonic activation of the α2–adrenoceptors following idazoxan administration. TRI treatment caused a robust increase in extracellular DA levels that was in part mediated by a serotonergic contribution. Therapeutic effects of the drugs examined in this study may be due to the enhancement of 5-HT, NE and/or DA neurotransmission.

The overall goal of this research was to understand the role of inter-kingdom signaling in enterohemorrhagic Escherichia coli (EHEC) infections of the human gastro-intestinal (GI) tract from the perspective of both the invading pathogen and the human intestinal epithelial cells, which they colonize. Differential gene expression of EHEC was studied upon exposure to the human neuroendocrine hormones epinephrine and norepinephrine. We determined that these hormones increase EHEC chemotaxis, motility, biofilm formation, colonization of host cells, and virulence gene expression. We also studied the EHEC response to the GI tract commensal bacterial signaling molecules indole and autoinducer-2 (AI-2). We observed that indole decreases all the EHEC phenotypes that are increased by the human hormones and represses EHEC virulence. However, the effect of AI-2 was similar to that observed with hormones and opposite to that observed with indole, i.e. AI-2 increases EHEC virulence phenotypes. We studied changes in host cell transcriptome in the presence of the commensal bacterial signal indole. Indole increases expression of genes involved in tight junction and gap junction formation, and production of mucins and actin cytoskeleton genes. Indole also down-regulates genes encoding for pro-inflammatory cytokines, chemokines, and Toll-like receptors. The gene expression results were confirmed with phenotypic assays where we observed an increase in trans-epithelial resistance, increase in the anti-inflammatory cytokine IL-10, decrease in the pro-inflammatory cytokine IL-8, decrease in the activity of the pro-inflammatory transcription factor NF-κB, and decrease in colonization by EHEC of the indole-pre-treated HCT-8 cells. We established that factors secreted by epithelial cells are important determinants of EHEC virulence. Gene expression studies showed that 34 out of 41 LEE virulence genes were induced when EHEC was cultured in conditioned medium. In addition, the data showed increased expression of the shiga toxin-2 prophage 933W. These changes in gene expression were corroborated by a 5-fold increase in HCT-8 cell colonization and increased intracellular Stx2 phage titers. We determined that the HCT-8-secreted factor(s) was protein-based and that it was greater than 3 kDa in size. In conclusion, we have characterized the pathogen response to various eukaryotic and prokaryotic GI tract signals. We have established, for the first time, that the commensal bacterial signal indole is an inter-kingdom signal for the host epithelial cells. Overall, our studies provide a greater understanding of host-pathogen interactions.

The objective of this dissertation research was to determine the specific actions of chronically elevated catecholamines on; 1.) fetal growth and ß-cell function during the third trimester in vivo in an ovine model of placental insufficiency-induced intrauterine growth restriction (PI-IUGR), and 2.) regulation of insulin secretion in vitro utilizing the mouse insulinoma cell line Min6.At 0.7-gestation, fetal weights were not different but PI fetuses had lower (P<0.05) basal blood oxygen content, plasma glucose, IGF-1, and insulin concentrations and greater norepinephrine concentrations (891±211 vs. 292±65 pg/ml; P<0.05) compared to controls. Glucose-stimulated insulin secretion (GSIS) was lower in PI than control fetuses (0.34±0.03 vs. 1.08±0.06 ng/ml; P<0.05). ADR-block increased GSIS in PI fetuses (1.19±0.11) but decreased GSIS in controls (0.86±0.02 ng/ml). Insulin content per islet was not different between PI and control fetuses. We concluded that elevated fetal plasma norepinephrine, in PI fetuses at 0.7 gestation, precedes growth restriction and suppresses insulin concentrations, and ADR-block revealed compensatory β-cells stimulus-secretion responsiveness. Therefore, to determine the effects of chronic hypercatecholamine exposure on fetal growth and β-cell function independent of hypoglycemia and hypoxemia, we performed surgical sham or adrenal demedullation (AD) at 0.65 gestation on control and IUGR fetuses (n= 5 Control-Sham, 5 Control-AD, 5 IUGR-Sham, 5 IUGR-AD fetuses). Studies commenced at 0.9 gestation under ambient conditions and steady-state reversal of arterial pO2 between IUGR and control fetuses. Plasma norepinephrine was 5-fold higher in IUGR-Sham vs. Control-Sham and reduced in IUGR-AD fetuses to concentrations not different from Control-Sham fetuses. Fetal mass was lower in IUGR vs. control fetuses but 92% greater in IUGR-AD compared to IUGR-Sham fetuses. Basal plasma glucose and arterial pO2 were lower in IUGR-Sham vs. Control-Sham, and IUGR-AD vs. Control-AD fetuses. Basal and glucose-stimulated insulin concentrations compared to Control-Sham were lower in IUGR-Sham and IUGR-AD and Control-AD fetuses. Oxygenation improved GSIS in IUGR-Sham and IUGR-AD fetuses. In conclusion, hypoglycemia, hypoxemia and norepinephrine interdependently and differentially regulate aspects of fetal growth and β-cell function in the IUGR fetus. In Min6 cells, we determined that GSIS responsiveness is enhanced and adrenergic receptor α2A is desensitized cells following chronic exposure to epinephrine.

Diss. (sammanfattning) Stockholm : Karol. inst., 2002. / Härtill 4 uppsatser.

Thesis (Ph.D. in Neuroscience) -- University of Colorado Denver, 2008. / Typescript. Includes bibliographical references (leaves 140-153). Free to UCD Anschutz Medical Campus. Online version available via ProQuest Digital Dissertations;

Thesis (doctoral)--Rijksuniversiteit te Groningen.

Sleep loss alters both the concentration and activity of various aspects of the immune system. These alterations lead to increased susceptibility to infection and the progression of pathologies such as insulin resistance and atherosclerosis. Two proposed mechanisms of this alteration in immune function are the changes in both cortisol and sympathetic nervous system activity that accompany sleep deprivation. This work reviewed literature that measured the effects of periods of sleep restriction upon both cortisol and catecholamine concentrations within human subjects. Furthermore, studies which measured the effects of sleep loss upon these hormone levels and the associated changes in immune parameters were included. This thesis asserts that there is no defined pattern in reference to alterations of cortisol levels as a result of sleep deprivation. Furthermore, more evidence must be collected before implementing cortisol as a main effector of sleep loss upon immune system function. This dissertation, although repeatedly noting increased levels of norepinephrine following periods of sleep restriction, similarly argues that more research must be completed in order to declare that altered catecholamine concentrations as a result of sleep loss is a mechanism for altered immune function.

Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / Os anestÃsicos locais sÃo as drogas mais amplamente utilizadas na prÃtica odontolÃgica. O presente estudo teve como objetivo reportar a eficÃcia clÃnica e a seguranÃa terapÃutica da MepivacaÃna 2% com Epinefrina 1:100.000 (MEPI-E) e MepivacaÃna 2% com Norepinefrina 1:100.000 (MEPI-N) em infiltraÃÃo anestÃsica de dentes caninos superiores em voluntÃrios saudÃveis. Realizou-se um estudo do tipo ensaio clÃnico, prospectivo, randomizado, cruzado, triplo cego. Trinta pacientes foram randomizados e receberam 0,6 mL de ambas as soluÃÃes anestÃsicas, por meio de anestesia terminal infiltrativa, em caninos superiores. Foi avaliado o grau de dor durante a infiltraÃÃo anestÃsica por meio da escala visual analÃgica de dor (EVA). O tempo de induÃÃo anestÃsica foi mensurado pelo teste elÃtrico pulpar mensurando assim, o tempo necessÃrio para a efetivaÃÃo do bloqueio. Os dentes foram submetidos a testes elÃtricos em ciclos periÃdicos e avaliados por 60 minutos com a finalidade de verificar a eficÃcia anestÃsica em tecido dentÃrio. O teste de picada foi utilizado para mensurar a eficÃcia clÃnica em tecido mole, nos seguintes sÃtios: gengiva inserida vestibular, mucosa alveolar superior, mucosa labial superior e pele. TambÃm foi verificada difusÃo vestÃbulo-palatina da soluÃÃo anestÃsica. PressÃo arterial sistÃlica e diastÃlica, frequÃncia cardÃaca, saturaÃÃo de oxigÃnio e glicemia serviram como parÃmetros sistÃmicos de avaliaÃÃo da seguranÃa terapÃutica. Estabeleceu-se o nÃvel de significÃncia em 0,05 (5%), foram utilizados os software GraphPad Prism e o software SPSSÂ. Foram analisados um total de 60 punÃÃes anestÃsicas em 30 voluntÃrios do estudo. O grupo MEPI-N apresentou menor nÃvel de dor e desconforto durante a infiltraÃÃo anestÃsica, com diferenÃa estatisticamente significante (P = 0,0106) quando comparado ao grupo MEPI-E. 86,7% dos pacientes quando anestesiados com MEPI-N se apresentaram negativos ao teste elÃtrico num tempo &#8804; 30 segundos, contra 43,3% do grupo MEPI-E (P = 0,002). Na avaliaÃÃo da eficÃcia anestÃsica pulpar, resultados estatisticamente significantes foram observados nos tempos de 40, 50 e 60 minutos de avaliaÃÃo (P = 0,031, P = 0,021, P = 0,039 respectivamente) mostrando maior potÃncia ao grupo MEPI-N, na anÃlise da eficÃcia anestÃsica em lÃbio superior nos tempos 30, 35 e 40 minutos (P = 0,031) a superioridade tambÃm foi atribuÃda a soluÃÃo MEPI-N. NÃo houve diferenÃa estatÃstica na anÃlise intergrupos sob os parÃmetros de seguranÃa terapÃutica. NÃo foi observada significÃncia estatÃstica na anÃlise intergrupo em relaÃÃo aos parÃmetros sistÃmicos. Na anÃlise intragrupo observou-se que a pressÃo arterial sistÃlica e diastÃlica, a frequÃncia cardÃaca foram significantemente menores que a basal para alguns tempos em ambos os grupos. A mÃdia glicÃmica aos 30 minutos foi superior e estatisticamente significante ao basal. Resultados apontam que bloqueios anestÃsicos com MepivacaÃna 2% com Norepinefrina 1:100.000 sÃo capazes de conferir um melhor padrÃo anestÃsico sem contudo resultar em alteraÃÃes sistÃmicas. / Local anesthetics are the most widely drugs used in dental practice. The present study aimed to report the clinical efficacy and safety of therapeutic Mepivacaine 2% with Epinephrine 1:100,000 (MEPI-E) and Mepivacaine 2% with 1:100,000 norepinephrine (MEPI-N) in infiltration anesthesia of upper canine teeth in healthy volunteers. We conducted a clinical trial, prospective, randomized, crossover, triple blind. Thirty patients were randomly and received either 0.6 ml of both anesthetic solution through terminal infiltrative anesthesia in canines. The degree of pain during anesthetic infiltration was made by visual analog scale of pain (VAE). The induction time was measured by measuring electrical test pulp thus the time required for ensuring the locking. The teeth were subjected to electrical tests in periodic cycles and evaluated by 60 minutes in order to verify the effectiveness of anesthesia in dental tissue. The prick test was used to measure the clinical efficacy in soft tissue, at the following sites: buccal gingiva, upper alveolar mucosa, superior labial mucosa and skin. We also observed vestibular-palatal diffusion of the anesthetic. Systolic and diastolic blood pressure, heart rate, oxygen saturation and blood glucose were used as parameters for assessing the systemic therapeutic safety. Established the significance level of 0.05 (5%) were used GraphPad Prism  and SPSS Â. Were analyzed a total of 60 punctures anesthetic in 30 study volunteers. The MEPI-N group showed lower levels of pain and discomfort during the anesthetic infiltration, which was statistically significant (P = 0.0106) when compared to the MEPI-E. 86.7% when anesthetized with MEPI-N the electric test were negative a time &#8804; 30 seconds, against 43.3% of MEPI group-E (P = 0.002). In evaluating the anesthetic efficacy pulp, statistically significant results were observed in intervals of 40, 50 and 60 minutes of evaluation (P = 0.031, P = 0.021, P = 0.039 respectively) showing greater power to the MEPI-N group, in analyzing the effectiveness anesthesia in the upper lip at 30, 35 and 40 minutes (P = 0.031) showed superiority was also attributed to MEPI-N solution. There was no statistical difference between groups in the analysis under the parameters of therapeutic safety. There was no statistical significance in the intergroup analysis in relation to systemic parameters. Intragroup analysis showed that the systolic and diastolic blood pressure, heart rate were significantly lower than baseline for some time in both groups. The mean glucose at 30 minutes was higher and statistically significant at baseline. Results indicate that anesthetic blocks with 2% Mepivacaine with 1:100,000 norepinephrine are able to provide a better standard anesthetic but without result in systemic changes.

As espécies reativas de oxigênio (EROs) são intermediários de vias de sinalização que regulam eventos celulares relevantes na função de células musculares lisas vasculares como migração, proliferação e contração. A NADPH oxidase é a principal fonte enzimática de EROs com finalidade sinalizadora no sistema cardiovascular. Estudos do nosso grupo demonstraram que a proteína dissulfeto isomerase (PDI), uma chaperona redox do retículo endoplasmåtico é capaz de modular a geração de EROs e a ativação de vias de sinalização redox dependentes pela Ang II. Apesar dos recentes avanços na compreensão dos mecanismos que regulam a interação entre a PDI e NADPH oxidase, o papel desta chaperona nos efeitos biológicos relacionados a EROs, como a contração vascular, não estão esclarecidos. A inibição da resposta contrátil pelo DTNB, um oxidante de tióis sugere o envolvimento de proteínas contendo tióis como a PDI e a NADPH oxidase na contração de aortas isoladas estimuladas com Ang II. Estes resultados foram confirmados por experimentos que demonstraram a expressão de PDI em todas as camadas vasculares da aorta de ratos Wistar e uma co-localização desta proteína com a isoforma NOX-1. A inibição da PDI diminuiu a geração de EROs e a reatividade vascular induzida por Ang II e NOR independente da presença do endotélio. A investigação dos mecanismos envolvidos sugere um papel da PDI na mobilização de cálcio dos estoques intracelulares via NADPH oxidase. A ativação de MAP quinases contribuiu para aumentar a mobilização de cálcio intracelular em aortas estimuladas com Ang II e NOR. No entanto, a inibição da PDI reduziu a fosforilação da ERK 1/2 em aortas estimuladas com Ang II, mas não com NOR. A análise conjunta dos nossos resultados sugere que mecanismos redox dependentes e independentes estariam envolvidos na regulação da resposta contrátil à Ang II e NOR pela PDI. / The reactive oxygen species (ROS) are intermediates of signaling pathways which regulates cellular events relevant for the vascular smooth cells function as migration, proliferation and contraction.The NADPH oxidase is the main enzimatic source of ROS with the signaling purpose on the cardiovascular system. We previously demonstrated that the protein disulfide isomerase (PDI), a redox chaperone of endoplasmic reticulum, is able to modulate the ROS generation and the activation of signaling redox ways dependent of Ang II. Although the recent advances in the understanding of mechanisms that regulate the interaction of PDI and NADPH oxidase, the role of this chaperone in the biological effects related to ROS, as vascular contraction, are not well clarified. The inhibition of the contractile response by DTNB, an oxidant thiol, suggest the involvement of proteins containing thiols as the PDI and NADPH oxidase in the contraction of isolated aortas stimulated with Ang II. These results were confirmed by experiments that demonstrated the PDI expression in Wistar rats vascular layers and a co-localization of this protein with the NOX-1 isoform. The PDI inhibition decreased ROS generation and the Ang II and NOR induced vascular reactivity endothelium independent. The investigation of involved mechanisms suggest that one PDI role is the calcium mobilization from the intracellular storage by NADPH oxidase way. The MAPkinases activation contributed to increase de intracellualar calcium in stimulated aortas with AngII and NOR. However, the PDI inhibition reduced the ERK ½ fosforilation in AngII- stimulated aorta, but not with NOR. The analyses of all of our results suggests that dependent and independent redox mechanims were involved in the regulation of contractile response to Ang II and NOR by PDI.