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Economic feasibility of an integrated semi-batch reactive distillation operation for the production of methyl decanoateAqar, D.Y., Mujtaba, Iqbal 28 March 2022 (has links)
Yes / The formation of methyl decanoate (MeDC) by esterification reaction of decanoic acid with methanol through batch/continuous reactive distillation columns is operationally challenging, energy intensive and thus cost intensive operation due to complex thermodynamic behaviour of the reaction scheme. Aiming to overcome the equilibrium restriction of the decanoic acid (DeC) esterification operation, to improve the process efficiency and to reduce the total annualised cost (TAC), the semi-batch distillation column (SBD) and the recently proposed integrated semi-batch distillation column configuration (i-SBD) are investigated here. The performances of each of these column operations are evaluated in terms of minimum TAC for a given separation task. In both column configurations, additional operating constraints are considered into the optimization problem to prevent flooding of still pot due to the continuous charging of methanol into it. This study shows the superiority of i-SBD mode of operation over SBD operation in terms of TAC. Also, the optimization results for a defined separation task indicate that the performance of multi-interval control policy is overwhelmingly superior to the single-interval control operation in terms of operating batch time, and overall annual cost in the i-SBD system providing about a time saving of 82.75%, and cost (TAC) saving of 36.61% for a MeDC (product) concentration of 0.945 molefraction.
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Growth Hormone and Anabolic Androgenic Steroids : Effects on Neurochemistry and CognitionGrönbladh, Alfhild January 2013 (has links)
Growth hormone (GH) stimulates growth and metabolism but also displays profound effects on the central nervous system (CNS). GH affects neurogenesis and neuroprotection, and has been shown to counteract drug-induced apoptosis in the brain. Anabolic androgenic steroids (AAS), mainly abused for their anabolic and performance-enhancing properties, can cause several adverse effects, such as cardiovascular complications, sterility, depression, and aggression. GH and AAS are both believed to interact with several signaling systems in the CNS. The aim of this thesis was to further investigate the impact of GH and AAS on neurochemistry and cognitive functions. Recombinant human GH (rhGH) and the steroid nandrolone decanoate (ND) were administered, separately and in combination with each other, to male rats. The results demonstrated that administration of GH improved spatial memory, assessed in a water maze test. Furthermore, GH induced alterations of the GABAB receptor mRNA expression, density, and functionality in the brain, for example in regions associated with cognition. GH also altered the mu opioid peptide (MOP) receptor, but not the delta opioid peptide (DOP) receptor functionality in the brain. Thus, some of the GH effects on cognition may involve effects on the GABAB receptors and MOP receptors. ND, on the contrary, seemed to induce impairments of memory and also altered the GABAB receptor mRNA expression in the brain. Furthermore, ND lowered the IGF-1 plasma concentrations and attenuated the IGF-1, IGF-2, and GHR mRNA expression in the pituitary. In addition, significant effects of GH and ND were found on plasma steroid concentrations, organ weight, as well as body weight. In conclusion, this thesis contributes with further knowledge on the cognitive and neurochemical consequences of GH and ND use. The findings regarding ND are worrying considering the common use of AAS among adolescents. GH improves memory functions and affects signaling systems in the brain associated with cognition, hence the hypothesis that GH can reverse drug-induced impairments is further strengthened.
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The Impact of Nandrolone Decanoate on Neuropeptidergic Mechanisms Related to Cognition, Aggression, Reward and DependenceMagnusson, Kristina January 2009 (has links)
The abuse of anabolic androgenic steroids (AAS) is becoming increasingly common and may result in a range of physiological as well as psychological effects such as altered behavior in terms of increased aggression, cognitive dysfunction and addictive behavior. AAS comprise testosterone and its derivatives, of which nandrolone is one of the more common. Previous studies have shown nandrolone-induced effects in male rats on peptide levels within the Substance P (SP) system and the dynorphinergic system; these effects may be linked to some of the reported behavior alterations. The studies presented in this thesis aimed to investigate the mechanisms underlying these peptide alterations and also to further investigate neuropeptidergic effects attributed to nandrolone administration. The results display significant effects on the enzymatic conversion of SP and Dynorphin A into their bioactive metabolites SP(1-7) and Leu-enkephalin-Arg6, respectively, as a result of nandrolone treatment. More profound investigations on the dynorphinergic system displayed effects on the kappa opioid receptor density in various brain regions. There was also a significant increase in the expression of the gene transcript of prodynorphin in the hippocampus, a brain region associated with cognitive processes. In addition, impaired spatial learning and memory in the Morris water maze task following nandrolone administration was encountered. The results provide further understanding regarding neuropeptidergic mechanisms underlying AAS-induced behavioral effects.
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Análise hormonal, imunolocalização e quantificação dos receptores de andrógenos (AR) e estrógenos (ER-α E ER-β) em ovário e útero de ratas submetidas a diferentes doses de decanoato de nandrolona: avaliação nos períodos pós-tratamento e pós-recuperação / Hormonal analysis, immunolocalization and quantification of androgen receptors (AR) and estrogen (ER-α AND ER-β) in ovarian and uterus of rats treated with different doses of nandrolone decanoate: assessment in post-treatment and post-recovery periodsSimão, Vinícius Augusto [UNESP] 26 January 2016 (has links)
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Previous issue date: 2016-01-26 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Fundação para o Desenvolvimento da UNESP (FUNDUNESP) / Embora sejam extensas as opções de aplicação terapêutica dos esteroides anabólicos androgênicos (EAA), é crescente na sociedade o uso destas drogas por razões estéticas e este consumo tem aumentado principalmente entre as mulheres nas últimas décadas. É amplamente relatado que os EAA comprometem a saúde e promovem efeitos adversos na reprodução, no entanto, pouca atenção é dada a respeito dos efeitos promovidos pelos EAA no ciclo estral, na morfologia ovariana e uterina e na regulação da função ovariana após os períodos de tratamento e de recuperação. Nenhum relato foi obtido na literatura, quanto à administração de diferentes doses de EAA e a possibilidade de reversibilidade dos efeitos colaterais. Assim, o objetivo do projeto é avaliar o efeito de diferentes doses do esteroide decanoato de nandrolona (DN) no ciclo estral e nos ovários e útero de ratas albinas com ênfase no controle da imunoexpressão do AR, ERs, CYP450 aromatase e Inibina-A do tecido ovariano e nos níveis hormonais sexuais, e também se há recuperação dos prejuízos reprodutivos após a interrupção do tratamento esteroidal. Ratas Wistar foram tratadas com DN nas doses de 1,87, 3,75, 7,5 e 15 mg/kg ou óleo mineral (grupos controle) por 15 dias via subcutânea. Os animais foram divididos em três procedimentos: (a) tratamento durante 15 dias; (b) tratamento seguido por recuperação de 30 dias; (c) tratamento seguido por recuperação de 60 dias. O ciclo estral foi monitorado diariamente e no final de cada período os animais foram sacrificados. Durante o período de tratamento com DN e no pós-recuperação de 30 dias, os animais exibiram diestro persistente, que manteve-se somente no grupo de 15 mg DN/kg no período de recuperação de 60 dias. O peso ovariano foi reduzido e o uterino aumentado na comparação com o controle em função do tratamento com DN e somente foi recuperado no 60 dias pós-tratamento nos grupos que restabeleceram o ciclo estral. Houve uma redução (p<0,05) no número de corpos lúteos, folículos antrais e em crescimento e diminuição da camada endometrial uterina, em contraste com um aumento (p<0,05) nos folículos atrésicos e das camadas do miométrio e perimétrio nas ratas DN de maneira dose e período-dependente. Alterações histopatológicas notáveis ocorreram nos ovários e útero de todos os grupos tratados com DN em função do período avaliado e estiveram relacionados aos níveis dos hormônios sexuais e de expressão dos receptores ovarianos alterados de maneira dose-específica. Concluiu-se que o tratamento experimental com DN promoveu toxicidade ovariana e uterina em ratas de maneira dose-dependente e que o período de recuperação de 60 dias foi suficiente para a reversibilidade dos efeitos colaterais apenas no tratamento com as menores doses do esteroide, de forma que os níveis hormonais e de expressão dos receptores ovarianos puderam se recuperar após marcante desregulação promovida pelo tratamento androgênico. / Although are extensive the options of therapeutic use of anabolic-androgenic steroids (AAS), the use of these drugs for aesthetic reasons is growing in society and this consumption has increased mainly among women in recent decades. It is widely reported that the AAS compromise the health and promote adverse effects on reproduction, however, little attention is given on the effects promoted by the AAS in the estrous cycle, in ovarian and uterine morphology and in the regulation of ovarian function after treatment periods and recovery. No report has been obtained from the literature regarding the administration of different doses of synthetic steroids and the possibility of reversibility of side effects. The objective of this project is to evaluate the effect of different doses of steroid nandrolone decanoate (ND) in the estrous cycle and ovaries and uterus of albino rats with emphasis on control of AR immunoexpression, ERs, CYP450 aromatase and inhibin-A in the ovarian tissue and sexual hormone levels, and evaluate if there is recovery of possible reproductive damages after cessation of steroid treatment. Female Wistar rats were treated with ND at doses of 1.87, 3.75, 7.5 and 15 mg/kg or received mineral oil (control groups estrus and diestrus) for 15 days subcutaneously. The animals were divided into three procedures: (a) treatment for 15 days; (b) treatment followed by recovery to 30 days; (c) treatment followed by recovery for 60 days. The estrous cycle was monitored daily and at the end of each period the animals were sacrificed. During the ND treatment period and after recovery for 30 days, all animals exhibited persistent diestrus, which was maintained only in the group of 15 mg ND/kg after the recovery period of 60 days. The ovarian weight has been reduced and the uterine has increased (p<0.05) in comparison with the control due to the treatment with ND and it was only recovered at 60 days post-treatment in the groups that reestablished the estrous cycle. There was a reduction (p<0.05) in the number of corpora lutea, antral and growing follicles and decreased in uterine endometrial layer, in contrast with an increase (p<0.05) in atretic follicles, myometrium and perimetrium in the androgenized rats in a dose and time-dependent manner. Remarkable histopathological changes occurred in the ovaries and uterus of all groups treated with ND depending on the period assessed and were related to the levels of sex hormones and expression of altered ovarian receptors in a dose-specific manner. It was concluded that the experimental treatment with ND promoted ovarian and uterine toxicity in rats in a dose-dependent manner and the 60-day recovery period was sufficient for the reversibility of side effects only in treatment with lower steroid doses in a way that hormonal levels and expression of ovarian receptors could recover after remarkable dysregulation promoted by the androgenic treatment. / FAPESP: 2013/14510-0 / FUNDUNESP: 2178/002/14
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Efeitos do metoprolol sobre as alterações histomorfológicas do coração produzidas pelo decanoato de nandrolona em ratosSantos, Rosilene Aparecida Reis Rodrigues dos 20 August 2009 (has links)
The anabolic androgenic steroids (AAS) came from testosterone, with restricted use in
medicine in some specific clinical conditions, and when correctly administrated are well
tolerated. However, there is a potential risk to health the use of AAS without medical
prescription and above the recommended dose, becoming evident the collateral effects. The
risk of adverse cardiovascular effects increasing is a main concerning. The abusive use of
anabolic androgenic steroids (AAS) is associated with left ventricular hypertrophy. The
decanoate of nandrolone (nandrolone) is one of the most used AAS in the world. The
regression of left ventricular hypertrophy is a point of interest because of the possible
reduction of bad prognostic that it causes to the individual. Beta-blockers can revert the
variations associated to ventricular remodeling and can show the progressive deterioration
benefits from ventricular dysfunction. In this study was evaluated the effects of metoprolol on
histomorphological profile of heart induced by AAS in rats. Four groups, each with 10 rats,
were studied: 1) Control Group (C): rats that received twice a week injections of olive oil
during five weeks as a control group (1 ml intramuscular);2) Nandrolone Group (N): rats that
received twice a week injections of nandrolone during five weeks (15 mg/kg weight,
intramuscular); 3) Metoprolol Group (M): rats that received twice a week injections of olive
oil (1 ml intramuscular) during five weeks and daily injections of metoprolol (4 mg/kg
weight, intraperitonial) during five weeks and 4) Nandrolone-Metoprolol Group (NM): rats
that received twice a week injections of nandrolone (15 mg/kg weight, intramuscular) during
five weeks and daily injections of metoprolol (4 mg/kg weight, intraperitonial) during five
weeks. The animals were weighed to control body weight and heart beat frequency. The heart
weight/animal weight ratio was quantified. The evaluation of ventricular remodelling was
obtained through histological processing and morphological analyses, measuring miocytes
diameter using HL Image 97. These microphotographies allowed the transversal diameter
measurement of, at least, five ventricular fibers, with a total of 125 fibers measured by
animal. The diameter of each fiber, in micrometers, was obtained in the HL Image 97
program.
It was verified that the animals from Nandrolone (N) group showed a significant
increasing of the ventricular fiber diameter compared with control group (C). In the
association of nandrolone and metoprolol (NM) the diameter was 50 % lower than the group
that received only nandrolone (N).
The nandrolone decanoate promotes ventricular remodeling characterized by the
increasing of myocardiocytes transversal diameter and the metoprolol associated with this
nandrolone causes cardioprotective and repairing effect, decreasing the induced myocardium
hypertrophy / Os esteróides anabólico-androgênicos (EAA) são derivados da testosterona, de uso
exclusivo na medicina para certas condições clínicas e, quando administrados corretamente,
são em geral bem tolerados. Porém existe risco potencial à saúde quando o uso dos EAA
ocorre sem vigilância médica, sem indicação clínica adequada e são empregadas doses acima
das recomendadas, tornando-se prováveis os efeitos colaterais indesejados. Especialmente
preocupante é o aumento do risco de efeitos adversos cardiovasculares. O uso abusivo de
esteróides anabolizantes está associado ao aparecimento de hipertrofia ventricular esquerda
(HVE). O decanoato de nandrolona (NAN) é um dos EAA mais utilizados no mundo. O
tratamento visando a regressão da HVE vem se tornando, nos últimos tempos, um foco de
interesse, principalmente pela possível redução do mau prognóstico que ela traz. Os
bloqueadores beta-adrenérgicos podem reverter às alterações associadas a este tipo de
remodelamento e evidenciam seus benefícios na inibição da deterioração progressiva da
disfunção ventricular. Neste estudo, avaliamos os efeitos do metoprolol sobre as alterações
histomorfológicas do coração produzidas pelo NAN. Foram estudados quatro grupos de ratos
com 10 animais em cada um deles e assim identificados: 1) Grupo Controle (C): ratos que
receberam injeção duas vezes por semana de óleo de oliva por cinco semanas como grupo
controle (1ml, via intramuscular); 2) Grupo Nandrolona (N): ratos que receberam injeção
duas vezes por semana de NAN por cinco semanas (15mg/kg de peso, intramuscular); 3)
Grupo Metoprolol (M): ratos que receberam injeção, duas vezes por semana, de óleo de oliva,
por cinco semanas (1ml, intramuscular) e injeção diária de metoprolol por cinco semanas
(4mg/kg de peso, intra peritoneal) e 4) Grupo Nandrolona-Metoprolol (NM): ratos que
receberam injeção, duas vezes por semana, de NAN, por cinco semanas (15mg/kg de peso,
intramuscular) e injeção diária de metoprolol por cinco semanas (4mg/kg de peso, intra
peritoneal). Os animais foram controlados quanto ao peso e à frequência cardíaca. A relação
entre o peso cardíaco e o peso corporal também foram quantificados. A avaliação do
remodelamento ventricular foi obtida por processamento histológico e análises
morfométricas, medindo-se o diâmetro dos miócitos usando o software HL Image. Por meio
da análise de imagem computacional foram mensurados o diâmetro de 125 fibras musculares
ventriculares de cada animal.
Verificou-se que os animais do grupo Nandrolona(N) apresentavam aumento
significante do diâmetro das fibras musculares ventriculares em relação ao grupo controle (C).
Na associação da nandrolona com o metoprolol (N-M) o diâmetro foi 50% menor em relação
ao grupo que recebeu somente nandrolona (N).
O decanoato de nandrolona causa remodelamento ventricular caracterizado por
aumento do diâmetro transversal dos cardiomiócitos e o metoprolol, associado a este
anabolizante, exerce efeito modulador neste processo reduzindo a HVE induzida. / Mestre em Ciências da Saúde
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Anabolic Androgenic Steroids : Effects on Neuropeptide Systems in the Rat BrainHallberg, Mathias January 2005 (has links)
<p>Anabolic-androgenic steroids (AAS) have been used in clinics for decades. The misuse of AAS has previously been attributed merely to sport athletes, taking AAS with intentions to increase muscle mass, enhance physical performance and to improve results in competitions. Today, the misuse of AAS has spread to adolescents and young adults not connected to sports. Alarmingly, many reports are pointing at severe psychiatric adverse effects among AAS abusers, which include mood swings, mania, anxiety, depression and aggression. Numerous examples of severe and often unprovoked violence and brutal crimes have been connected to AAS abuse and there is a strong need for a better understanding of the underlying biochemical events that might account for the adverse behaviors induced by AAS. The general aim of this thesis was to study the effect of chronic AAS administration on neuropeptide circuits in the rat brain associated with the regulation of rewarding effects, memory, anxiety, depression and aggression, using nandrolone decanoate as a prototype AAS.</p><p>Results demonstrated that daily administration of AAS to rats in doses comparable to those taken by AAS abusers, in certain brain structures significantly affected, <i>a</i>) the levels of the opioid peptides dynorphin B and Met-enkephalin-Arg<sup>6</sup>Phe<sup>7</sup>, <i>b</i>) the levels of the tachykinin substance P (SP), <i>c</i>) the density of the SP neurokinin 1 (NK1) receptor, <i>d</i>) the level of the SP metabolite SP<sub>1-7 </sub>that frequently exerts opposite effects to SP, <i>e</i>) the SP<sub>1-7 </sub>generating enzyme substance P endopeptidase (SPE) and finally, <i>f</i>) the levels of the neuropeptide calcitonin gene-related peptide (CGRP) often co-localized with SP. The alterations seen in the levels and activities of these neurochemical components are in many aspects compatible with behaviors typified among AAS abusers.</p>
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Anabolic Androgenic Steroids : Effects on Neuropeptide Systems in the Rat BrainHallberg, Mathias January 2005 (has links)
Anabolic-androgenic steroids (AAS) have been used in clinics for decades. The misuse of AAS has previously been attributed merely to sport athletes, taking AAS with intentions to increase muscle mass, enhance physical performance and to improve results in competitions. Today, the misuse of AAS has spread to adolescents and young adults not connected to sports. Alarmingly, many reports are pointing at severe psychiatric adverse effects among AAS abusers, which include mood swings, mania, anxiety, depression and aggression. Numerous examples of severe and often unprovoked violence and brutal crimes have been connected to AAS abuse and there is a strong need for a better understanding of the underlying biochemical events that might account for the adverse behaviors induced by AAS. The general aim of this thesis was to study the effect of chronic AAS administration on neuropeptide circuits in the rat brain associated with the regulation of rewarding effects, memory, anxiety, depression and aggression, using nandrolone decanoate as a prototype AAS. Results demonstrated that daily administration of AAS to rats in doses comparable to those taken by AAS abusers, in certain brain structures significantly affected, a) the levels of the opioid peptides dynorphin B and Met-enkephalin-Arg6Phe7, b) the levels of the tachykinin substance P (SP), c) the density of the SP neurokinin 1 (NK1) receptor, d) the level of the SP metabolite SP1-7 that frequently exerts opposite effects to SP, e) the SP1-7 generating enzyme substance P endopeptidase (SPE) and finally, f) the levels of the neuropeptide calcitonin gene-related peptide (CGRP) often co-localized with SP. The alterations seen in the levels and activities of these neurochemical components are in many aspects compatible with behaviors typified among AAS abusers.
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Efeitos do decanoato de nandrolona na homeostasia glutamatérgica e no comportamento agressivoKalinine, Eduardo January 2014 (has links)
Nos últimos anos, houve um aumento significativo no uso abusivo dos Esteróides Anabólicos Andrógenos (EAAs). Um dos efeitos comportamentais mais marcantes da administração crônica de EAAs como o Decanoato de Nandrolona (DN) é a indução do comportamento agressivo exacerbado. Atualmente o sistema glutamatérgico tem sido associado ao comportamento agressivo induzido pelos EAAs, principalmente no que se refere à modulação dos receptores N-Methyl-D-Aspartato NMDA (NMDAr). Nós investigamos os efeitos centrais e periféricos da administração do DN ao longo do tempo (4, 11 e 19 dias consecutivos de administração), e a participação de mecanismos glutamatérgicos. Para isso, camundongos CF-1 tratados com DN foram avaliados em relação ao comportamento agressivo pelo teste do intruso. Além disso, investigamos a captação de glutamato, o imunoconteúdo de GLT-1, os níveis de glutamato no líquido extracelular, e a participação dos NMDAr na manifestação do comportamento agressivo. O fenótipo agressivo foi evidenciado somente no longo tempo de exposição à DN (19 dias). Na mesma janela temporal que os animais apresentaram o fenótipo agressivo houve redução significativa de captação de glutamato em fatias cerebrais de córtex e hipocampo, como também a redução do imunoconteúdo do transportador astrocitário GLT-1 nas mesmas estruturas cerebrais. A administração de antagonistas de NMDAr como MK-801 e memantina antes do teste do intruso diminuiu o comportamento agressivo dos animais tratados cronicamente com DN a níveis iguais aos do grupo controle. Ainda, o comportamento agressivo induzido pela administração crônica de DN diminuiu a remoção do glutamato da fenda sináptica, culminando com o aumento do glutamato extracelular no SNC, o que resultou na hiperexcitabilidade dos NMDAr. Este trabalho enfatiza o papel da comunicação entre astrócitos e neurônios e a relevância da hiperstimulação de NMDAr na manifestação do comportamento agressivo. / Nandrolone decanoate (ND), an anabolic androgenic steroid (AAS), induces an aggressive phenotype by mechanisms involving glutamate-induced N-methyl-d-aspartate receptor (NMDAr) hyperexcitability. The astrocytic glutamate transporters remove excessive glutamate surrounding the synapse. However, the impact of supraphysiological doses of ND on glutamate transporters activity remains elusive. We investigated whether ND-induced aggressive behavior is correlated with GLT-1 activity, glutamate levels and abnormal NMDAr responses. Two-month-old untreated male mice (CF1, n=20) were tested for baseline aggressive behavior in the resident-intruder test. Another group of mice (n=188) was injected with ND (15mg/kg) or vehicle for 4, 11 and 19 days (short-, mid- and long-term endpoints, respectively) and was evaluated in the resident-intruder test. Each endpoint was assessed for GLT-1 expression and glutamate uptake activity in the frontoparietal cortex and hippocampal tissues. Only the long-term ND endpoint significantly decreased the latency to first attack and increased the number of attacks, which was associated with decreased GLT-1 expression and glutamate uptake activity in both brain areas. These alterations may affect extracellular glutamate levels and receptor excitability. Resident males were assessed for hippocampal glutamate levels via microdialysis both prior to, and following, the introduction of intruders. Long-term ND mice displayed significant increases in the microdialysate glutamate levels only after exposure to intruders. A single intraperitoneal dose of NMDAr antagonists, memantine or MK-801, shortly before the intruder test, decreased aggressive behavior. In summary, long-term ND-induced aggressive behavior is associated with decreased extracellular glutamate clearance and NMDAr hyperexcitability, emphasizing the role of this receptor in mediating aggression mechanisms.
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Efeitos do decanoato de nandrolona na homeostasia glutamatérgica e no comportamento agressivoKalinine, Eduardo January 2014 (has links)
Nos últimos anos, houve um aumento significativo no uso abusivo dos Esteróides Anabólicos Andrógenos (EAAs). Um dos efeitos comportamentais mais marcantes da administração crônica de EAAs como o Decanoato de Nandrolona (DN) é a indução do comportamento agressivo exacerbado. Atualmente o sistema glutamatérgico tem sido associado ao comportamento agressivo induzido pelos EAAs, principalmente no que se refere à modulação dos receptores N-Methyl-D-Aspartato NMDA (NMDAr). Nós investigamos os efeitos centrais e periféricos da administração do DN ao longo do tempo (4, 11 e 19 dias consecutivos de administração), e a participação de mecanismos glutamatérgicos. Para isso, camundongos CF-1 tratados com DN foram avaliados em relação ao comportamento agressivo pelo teste do intruso. Além disso, investigamos a captação de glutamato, o imunoconteúdo de GLT-1, os níveis de glutamato no líquido extracelular, e a participação dos NMDAr na manifestação do comportamento agressivo. O fenótipo agressivo foi evidenciado somente no longo tempo de exposição à DN (19 dias). Na mesma janela temporal que os animais apresentaram o fenótipo agressivo houve redução significativa de captação de glutamato em fatias cerebrais de córtex e hipocampo, como também a redução do imunoconteúdo do transportador astrocitário GLT-1 nas mesmas estruturas cerebrais. A administração de antagonistas de NMDAr como MK-801 e memantina antes do teste do intruso diminuiu o comportamento agressivo dos animais tratados cronicamente com DN a níveis iguais aos do grupo controle. Ainda, o comportamento agressivo induzido pela administração crônica de DN diminuiu a remoção do glutamato da fenda sináptica, culminando com o aumento do glutamato extracelular no SNC, o que resultou na hiperexcitabilidade dos NMDAr. Este trabalho enfatiza o papel da comunicação entre astrócitos e neurônios e a relevância da hiperstimulação de NMDAr na manifestação do comportamento agressivo. / Nandrolone decanoate (ND), an anabolic androgenic steroid (AAS), induces an aggressive phenotype by mechanisms involving glutamate-induced N-methyl-d-aspartate receptor (NMDAr) hyperexcitability. The astrocytic glutamate transporters remove excessive glutamate surrounding the synapse. However, the impact of supraphysiological doses of ND on glutamate transporters activity remains elusive. We investigated whether ND-induced aggressive behavior is correlated with GLT-1 activity, glutamate levels and abnormal NMDAr responses. Two-month-old untreated male mice (CF1, n=20) were tested for baseline aggressive behavior in the resident-intruder test. Another group of mice (n=188) was injected with ND (15mg/kg) or vehicle for 4, 11 and 19 days (short-, mid- and long-term endpoints, respectively) and was evaluated in the resident-intruder test. Each endpoint was assessed for GLT-1 expression and glutamate uptake activity in the frontoparietal cortex and hippocampal tissues. Only the long-term ND endpoint significantly decreased the latency to first attack and increased the number of attacks, which was associated with decreased GLT-1 expression and glutamate uptake activity in both brain areas. These alterations may affect extracellular glutamate levels and receptor excitability. Resident males were assessed for hippocampal glutamate levels via microdialysis both prior to, and following, the introduction of intruders. Long-term ND mice displayed significant increases in the microdialysate glutamate levels only after exposure to intruders. A single intraperitoneal dose of NMDAr antagonists, memantine or MK-801, shortly before the intruder test, decreased aggressive behavior. In summary, long-term ND-induced aggressive behavior is associated with decreased extracellular glutamate clearance and NMDAr hyperexcitability, emphasizing the role of this receptor in mediating aggression mechanisms.
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Efeitos do decanoato de nandrolona na homeostasia glutamatérgica e no comportamento agressivoKalinine, Eduardo January 2014 (has links)
Nos últimos anos, houve um aumento significativo no uso abusivo dos Esteróides Anabólicos Andrógenos (EAAs). Um dos efeitos comportamentais mais marcantes da administração crônica de EAAs como o Decanoato de Nandrolona (DN) é a indução do comportamento agressivo exacerbado. Atualmente o sistema glutamatérgico tem sido associado ao comportamento agressivo induzido pelos EAAs, principalmente no que se refere à modulação dos receptores N-Methyl-D-Aspartato NMDA (NMDAr). Nós investigamos os efeitos centrais e periféricos da administração do DN ao longo do tempo (4, 11 e 19 dias consecutivos de administração), e a participação de mecanismos glutamatérgicos. Para isso, camundongos CF-1 tratados com DN foram avaliados em relação ao comportamento agressivo pelo teste do intruso. Além disso, investigamos a captação de glutamato, o imunoconteúdo de GLT-1, os níveis de glutamato no líquido extracelular, e a participação dos NMDAr na manifestação do comportamento agressivo. O fenótipo agressivo foi evidenciado somente no longo tempo de exposição à DN (19 dias). Na mesma janela temporal que os animais apresentaram o fenótipo agressivo houve redução significativa de captação de glutamato em fatias cerebrais de córtex e hipocampo, como também a redução do imunoconteúdo do transportador astrocitário GLT-1 nas mesmas estruturas cerebrais. A administração de antagonistas de NMDAr como MK-801 e memantina antes do teste do intruso diminuiu o comportamento agressivo dos animais tratados cronicamente com DN a níveis iguais aos do grupo controle. Ainda, o comportamento agressivo induzido pela administração crônica de DN diminuiu a remoção do glutamato da fenda sináptica, culminando com o aumento do glutamato extracelular no SNC, o que resultou na hiperexcitabilidade dos NMDAr. Este trabalho enfatiza o papel da comunicação entre astrócitos e neurônios e a relevância da hiperstimulação de NMDAr na manifestação do comportamento agressivo. / Nandrolone decanoate (ND), an anabolic androgenic steroid (AAS), induces an aggressive phenotype by mechanisms involving glutamate-induced N-methyl-d-aspartate receptor (NMDAr) hyperexcitability. The astrocytic glutamate transporters remove excessive glutamate surrounding the synapse. However, the impact of supraphysiological doses of ND on glutamate transporters activity remains elusive. We investigated whether ND-induced aggressive behavior is correlated with GLT-1 activity, glutamate levels and abnormal NMDAr responses. Two-month-old untreated male mice (CF1, n=20) were tested for baseline aggressive behavior in the resident-intruder test. Another group of mice (n=188) was injected with ND (15mg/kg) or vehicle for 4, 11 and 19 days (short-, mid- and long-term endpoints, respectively) and was evaluated in the resident-intruder test. Each endpoint was assessed for GLT-1 expression and glutamate uptake activity in the frontoparietal cortex and hippocampal tissues. Only the long-term ND endpoint significantly decreased the latency to first attack and increased the number of attacks, which was associated with decreased GLT-1 expression and glutamate uptake activity in both brain areas. These alterations may affect extracellular glutamate levels and receptor excitability. Resident males were assessed for hippocampal glutamate levels via microdialysis both prior to, and following, the introduction of intruders. Long-term ND mice displayed significant increases in the microdialysate glutamate levels only after exposure to intruders. A single intraperitoneal dose of NMDAr antagonists, memantine or MK-801, shortly before the intruder test, decreased aggressive behavior. In summary, long-term ND-induced aggressive behavior is associated with decreased extracellular glutamate clearance and NMDAr hyperexcitability, emphasizing the role of this receptor in mediating aggression mechanisms.
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