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Dynamische Interaktion zwischen Leukozyten und Endothelzellen unter dem Einfluss von TNFα und Adalimumab / Dynamic interactions between leukocytes and endothelial cells under the influence of TNFα and adalimumabLockmann, Anike L. E. 31 March 2015 (has links)
In den letzten Jahrzehnten haben sich die so genannten Biologika auch zur Therapie der Psoriasis etabliert. Zu diesen Medikamenten gehört auch Adalimumab, welches als vollständig humaner Antikörper eines der Schlüsselzytokine in der Pathogenese der Psoriasis, TNFα, neutralisiert. Allerdings führt die Therapie nicht bei allen Patienten zu ausreichendem Wirkerfolg. Da bisher vor Beginn der Therapie nicht zwischen den Patienten, die von der Therapie profitieren, und denen, die keine ausreichende Wirkung erfahren, unterschieden werden kann, werden die letzteren unnötigerweise den Risiken und Nebenwirkungen dieser Therapie ausgesetzt. In dieser Arbeit wurden die Interaktionen kultivierter Endothelzellen und Lymphozyten ex vivo unter dem Einfluss von Adalimumab untersucht. Insbesondere auf mögliche Unterschiede zwischen „Respondern“ und „Non-Respondern“ wurde im Hinblick auf die mögliche Entwicklung eines prädiktiven Tests für das Ansprechen auf Adalimumab ein Schwerpunkt gelegt.
Lymphozyten gesunder Probanden und von Psoriasis-Patienten wurden ex vivo hinsichtlich ihrer Interaktion mit kultivierten Endothelzellen (HUVEC), mit und ohne TNFα-Stimulation, untersucht. Hierbei wurden sowohl frisch isolierte als auch kryokonservierte Lymphozyten verwendet, da sich zwischen diesen keine Unterschiede in den funktionellen Flusskammer-Versuchen zeigten. Nach Stimulation der Endothelzellen mit TNFα kam es zu einem deutlichen Anstieg des Rollens und der festen Adhäsion aller Lymphozyten an den Endothelzellen. Allerdings zeigten sich im Ausmaß dieser Interaktion deutliche inter-individuelle Unterschiede. Obwohl diese auch bei Psoriasis-Patienten auftraten, konnten keine signifikanten Unterschiede zwischen „Respondern“ und „Non-Respondern“ beobachtet werden.
In den Untersuchungen zum Einfluss von Adalimumab auf TNFα-stimulierte Endothelzellen sowie die Interaktion dieser mit Lymphozyten ex vivo zeigte sich eine deutliche Abhängigkeit der Auswirkung vom Zeitpunkt der Behandlung. Erfolgte die Adalimumab-Behandlung vor oder gleichzeitig mit der TNFα-Stimulation der Endothelzellen, kam es zur Aufhebung der TNFα-induzierten Effekte sowohl in der Transkription der Adhäsionsmoleküle (PCR), der Expression dieser (Immunfluoreszenz-Mikroskopie) sowie der dynamischen Interaktionen mit Lymphozyten (Flusskammer). Eine dem TNFα nachfolgende Behandlung blieb ohne Wirkung, sodass davon auszugehen ist, dass sich die bereits induzierten Prozesse nicht mehr rückgängig machen lassen. Hier könnte eine Erklärung für das späte Eintreten der Adalimumab-Wirkung in vivo liegen.
Somit konnten in dieser Arbeit vier zentrale Ergebnisse erzielt werden:
Erstens, es wurde erstmals gezeigt, dass wichtige funktionelle Eigenschaften humaner Lymphozyten während der Kryokonservierung erhalten bleiben.
Zweitens, es wurden erstmals deutliche inter-individuelle Unterschiede im Ausmaß der Interaktion zwischen Lymphozyten ex vivo mit TNFα-stimulierten Endothelzellen nachgewiesen. Adalimumab unterdrückte diese dynamischen Interaktionen, sofern seine Zugabe vor oder gleichzeitig mit der TNF-Exposition erfolgte.
Drittens, diese inter-individuellen Unterschiede bestanden gleichermaßen bei gesunden Probanden und Psoriasis-Patienten.
Viertens, die funktionellen Unterschiede erlaubten keine Unterscheidung zwischen Psoriasis-Patienten, deren Erkrankung sich durch Adalimumab besserte („Responder“), und denen, deren Erkrankung nicht auf diese Therapie ansprach („Non-Responder“).
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THE MESOCORTICOLIMBIC DOPAMINE PATHWAY RECONSTITUTED IN VITRO: GLUTAMATE RECEPTORS AND CORTICOSTEROID-METHAMPHETAMINE NEUROTOXICITYBerry, Jennifer N 01 January 2013 (has links)
Stress promotes the use of methamphetamine and other recreational substances and is often implicated in relapse to stimulant use. Thus, it is of critical importance to examine the consequences of the co-occurance of stress and methamphetamine use. Activity of the glutamatergic N-methyl D-aspartate (NMDA) receptor system appears to be involved in the neurotoxic effects of both chronic stress and methamphetamine exposure. The current studies investigated the hypothesis that chronic pre-exposure to the stress hormone corticosterone (CORT) results in an increase of NMDA receptor activity and that this will potentiate the neurotoxic effects of methamphetamine (METH). Co-cultures of the ventral tegmental area, nucleus accumbens, and medial prefrontal cortex were pre-exposed to CORT (1 μM) for 5 days prior to co-exposure to METH (100 μM) for 24 hours to investigate the combined effects on neurotoxicity and protein density of NMDA receptor subunits. The combination of CORT and METH resulted in significant neurotoxicity within the medial prefrontal cortex compared to either CORT or METH alone. The CORT+METH-induced toxicity was attenuated by co-exposure to the NMDA receptor antagonist (2R)-amino-5-phosphonovaleric acid (APV; 50 μM) during the 24 hour CORT and METH co-exposure. Although CORT alone did not significantly alter the density of the NR1 and NR2B subunits of the NMDA receptor, METH exposure for 24 hours resulted in a significant loss of the polyamine sensitive NR2B subunit. Co-exposure to CORT and METH also resulted in decreased extracellular glutamate while not significantly altering extracellular dopamine. These results suggest an enhancement of NMDA receptor systems or downstream effectors in areas of the mesolimbic reward pathway following chronic pre-exposure to CORT, which leads to enhanced neuronal vulnerability to future excitotoxic insults. This may be of critical importance as use of psychostimulants such as METH and other drugs of abuse may produce excitotoxic events in these areas, thus further compromising neuronal viability.
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Entwicklung eines Tiermodells am akut instrumentierten Schwein zur Untersuchung endogener Opioidpeptide unter der extrakorporalen ZirkulationKruse, Lilian Charlotte 24 June 2010 (has links) (PDF)
Die extrakorporale Zirkulation unter Einsatz einer Herz-Lungen-Maschine kann postoperativ zu kontraktilen ventrikulären Funktionsstörungen führen, die Morbidität und Mortalität für betroffene Patienten erhöht. Diese kardiale Dysfunktion bezeichnet man als myokardiales Stunning, welche durch die globale Ischämie ausgelöst wird.
Das Phänomen der reversiblen kontraktilen Dysfunktion weißt eine hohe klinische Relevanz auf und ist somit in den vergangenen Jahrzehnten sowohl klinisch als auch experimentell intensiv erforscht worden. Dabei kamen unterschiedlichste Spezies, Methoden und Modelle zum Einsatz.
Ziel der vorliegenden Arbeit ist die Etablierung eines neuartigen akut instrumentierten Tiermodells, anhand dessen Folgen des kardiopulmonalen Bypasses und Wirkung des endogenen Opioidsystems auf myokardiales Stunning untersucht werden können.
Mit Hilfe des entwickelten Versuchsmodells können die Auswirkungen applizierter Opioidrezeptorantagonisten und die Effekte der kardiopulmonalen Zirkulation auf die kontraktile myokardiale Dysfunktion valide untersucht werden.
Als Versuchstiere wurden 50 männlich kastrierte Schweine der Rassenkreuzung „Deutsche Landrasse“ und „Yorkshireschwein“ eingesetzt. In Allgemeinanästhesie wurden die Tiere über eine Thorakotomie instrumentiert und anschließend elektrisch Kammerflimmern induziert. Nach Erreichen einer stabilen extrakorporalen Zirkulation unter der Herz-Lungen-Maschine wurde nach Ablauf der ischämischen Phase eine standardisierte Reaninmation und Weaning durchgeführt. Alle 50 Tiere konnten den Versuch erfolgreich durchlaufen. Die Analyse und Auswertung sämtlicher archivierter Daten und Proben der Versuchstiere wurde zu einem späteren Zeitpunkt durchgeführt.
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Comparative effects of the CRF agonist, ovine CRF, and CRF antagonist, astressin, on homecage behavior patterns and defense in the mouse / Comparative effects of the CRF agonist, ovine CRF, and antagonist, astressin, on homecage behavior patterns and defense in the mouseFarrokhi, Catherine F. Borna January 2005 (has links)
Thesis (M.A.)--University of Hawaii at Manoa, 2005. / Includes bibliographical references (leaves 34-45). / 52 leaves, bound ill. 29 cm
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Central vestibular compensation : the role of the GABA B receptor /Magnusson, Anna K., January 2002 (has links) (PDF)
Diss. Linköping : Univ., 2003. / Härtill 4 uppsatser.
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Beta 1 and Alpha 2C adrenergic receptor polymorphisms and response to beta blockers in heart failure patients /Zolty, Ronald. January 2007 (has links)
Thesis (Ph.D. in Clinical Science) -- University of Colorado Denver, 2007. / Typescript. Includes bibliographical references (leaves 130-142). Free to UCD affiliates. Online version available via ProQuest Digital Dissertations;
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Cholesterol and Phospholipid Modulation of BK[subscript Ca] Channel Activity and Ethanol Sensitivity: a dissertationCrowley, John J. 01 June 2003 (has links)
The large conductance Ca++-activated K+ channel (BKCa) regulates neuronal excitability through the efflux of K+, in response to membrane depolarization and increases in intracellular Ca++. The activity of the BKCa channel is increased by acute exposure to ethanol (EtOH), which is thought to underlie, in part, the influence of the drug on peptide hormone release from neurohypophysial nerve terminals (Dopico et al., 1996, 1998). Moreover, chronic EtOH exposure attenuates acute drug action on hormone release, and reduces the sensitivity of BKCa channels to acute EtOH exposure (Knott et al., 2002). The factors regulating EtOH action on BKCa channels are not well understood. Several lines of evidence suggest, however, that the lipid composition of the plasma membrane may influence channel sensitivity to the drug. The plasma membrane is highly complex in its organization (Welti and Glaser, 1994; Brown and London, 1998). There is a growing body of literature indicating that the local lipid composition of the membrane can influence the function of ion channels, including BKCa (Chang et al., 1995a, b; Moczydlowski et al., 1985; Park et al., 2003; Turnheim et al., 1999). Interestingly, chronic exposure to EtOH in animal models results in alterations in the composition of synaptic plasma membranes, including changes in the amount and distribution of membrane cholesterol (CHS) (Chin et al., 1978; Chin et al., 1979; Wood et al., 1989). The significance of these alterations is unclear. Here, we set out to determine the ability of membrane lipids to modulate BKCa channel activity and EtOH sensitivity. To address this, we implement the planar lipid bilayer technique, allowing control of both the protein and lipid components of the membrane. Native BKCa channels retain EtOH sensitivity in this reductionist preparation (Chu et al., 1998), and we extend the study here to examine cloned human brain (hslo) BKCachannels.
We show here that hslo channels maintain their characteristic large conductance, voltage and Ca++-dependent gating, and sensitivity to 50 mM EtOH in bilayers cast from a 3:1 mixture of 1-pamiltoyl-2-oleoyl-phosphatidylethanolamine (POPE) and 1-pamiltoyl-2-oleoyl-phosphatidylserine (POPS). The addition of CHS to the bilayer decreases both the basal activity and EtOH sensitivity of the channels, in a concentration-dependent manner. This lends support to the notion that alterations in plasma membrane CHS levels following chronic EtOH exposure may reflect adaptations to the acute actions of the drug on ion channels. Furthermore, the EtOH sensitivity and CHS modulation of these reconstituted hslo channels are greatly reduced in the absence of negatively charged POPS in the bilayer (pure POPE). Based on these findings, we look to gain mechanistic insight into the lipid headgroup and acyl chain properties that may regulate BKCa channel modulation by EtOH and CHS. When POPS is replaced with the uncharged lipid 1-palmitoyl-2-oleoyl-phosphatidylcholine (POPC), the hslo response to EtOH and CHS is restored, suggesting that the loss of negative surface charge or PS headgroup structure itself cannot explain the lack of channel modulation by these agents in POPE bilayers. Moreover, increases in the proportion of unsaturated acyl chains in the bilayer cannot significantly influence the hslo response to EtOH. The loss of EtOH sensitivity in pure POPE and CHS-containing bilayers may, therefore, reflect the propensity of POPE and CHS to form nonlamellar (nonbilayer) structures. Regarding the basal activity of the channel, we demonstrate that decreases in negative surface charge, increases in the proportion of unsaturated acyl chains, and increases in the complexity of head group interactions can all influence the steady-state activity of reconstituted hslochannels, relative to control POPE/POPS (3:1) bilayers. Overall, these data further suggest the ability of the local lipid environment to regulate the basal function and EtOH sensitivity of an ion channel protein.
Parts of this dissertation have appeared in separate publications:
Treistman, S.N., O'Connell, R.J., and Crowley, J.J. (2002). Artificial Bilayer Techniques in Ion Channel Study. In Methods in Alcohol-Related Neuroscience Research, D. Lovinger and Y. Liu, eds. (Boca Raton, Florida: CRC Press)
Crowley, J.J., Treistman, S.N., and Dopico, A.M. (2003). Cholesterol antagonizes ethanol potentiation of human BKCA channels in binary phospholipid bilayers. Mol. Pharma. 64(2):364-372.
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Signal Transduction Mechanisms for the Stimulation of Lipolysis by Growth Hormone: A DissertationYip, Rupert G. 01 August 1994 (has links)
The purpose of this study was to investigate the mechanism of action of lipolysis by growth hormone in rat adipocytes. GH-induced lipolysis, in contrast to that of isoproterenol (ISO), is slow in onset (lag time >1h), small in magnitude (~2X basal). and requires corticosteroid. Evidence for direct coupling between GH receptors and adenylyl cyclase or G-proteins is lacking, and although we could detect no measurable change in cAMP content after treatment with GH + dexamethasone (Dex), it is likely that cAMP activation of protein kinase A is a central event in GH-induced lipolysis. Rp-cAMPS, a competitive antagonist of cAMP was equally effective in decreasing lipolysis in tissues treated with GH/Dex or a comparably lipolytic dose of ISO. Incorporation of 32P from γ-32P-ATP into kemptide, a synthetic oligopeptide substrate for protein kinase A, was increased in homogenates of GH/Dex-treated tissue. This increase was correlated with increased lipolysis. Earlier estimates based upon 32P-ribosylation of Gi catalysed by pertussis toxin (PTx) suggested that the abundance of Gi in adipocyte membranes was decreased 4h after treatment of hypophysectomized rats with GH. We therefore examined the possibility that changes in amount or distribution of G-proteins in adipocyte membranes might account for the lipolytic action of GH. Homogenates of GH/Dex-treated and control adipocytes were subjected to differential centrifugation and the abundance of G-proteins in low speed, l6k x g (16k), pellets and high speed, 100k x g (100k), pellets were determined by quantitative Western analysis with densitometry. A 35% loss of Giα2 from the l6k pellet compared from tissues treated with GH/Dex was associated with a 70% increase of Giα2 in the 100k pellet. No change in Gsα was observed in the l6k pellet but a 35% loss of Gsα was seen in the 100k pellet. The G proteins in the l6k pellet were fractionated on a continuous sucrose gradient followed by quantitation with Western analysis or autoradiography after 32P-NAD ribosylation. Giα2 was consistently shifted from heavier to lighter fractions of the l6k pellet after treatment with GH/Dex. Similar shifts of Gsα were not seen. The distribution of 32P-labelled proteins was comparably altered after incubation of homogenates of control and GH/Dex treated adipocytes with PTx and 32P-NAD. These shifts were blocked by treatment of adipocytes with 100μM colchicine which also blocked the lipolytic action of GH/Dex. We propose that an action of GH/Dex on the cytoskeleton of fat cells may change the cellular distribution of G-proteins in a manner that produces a relative decrease in the tonic inhibitory influence of Gi on adenylyl cyclase.
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Controle alternativo da podridão radicular (Sclerotium rolfsii Sacc.) em feijão-caupi [Vigna unguiculata (L.) Walp.] (Fabaceae) / Alternative control of Sclerotium rolfsii Sacc. In cowpea [Vigna unguiculata (L.) Walp.] (Fabaceae)Santos, Inaura Patrícia da Silva 19 April 2010 (has links)
The cowpea, Vigna unguiculata (L.) Walp., is known as feijão-de-corda and feijão-verde , among others, is one of the main cultures exploited by small producers of the Northeast region of Brazil. Among the phytopathogens that affects its productivity, Sclerotium rolfsii Sacc. is noteworthy, causing the stem rot in several cultures around the world. The objective of this work was to evaluate the alternative control of S. rolfsii Sacc. in saplings of V. unguiculata (L.) Walp. trough the biocontrol of antagonists, organic residues incorporation to the soil, utilization of essential oils, plant extracts and mineral nutrition. The work was developed in the Laboratory de Phytopathology and in the vegetation house of CECA/UFAL. The pathogen was obtained trough the isolations of cowpea with symptoms of the disease and, afterwards, it was cultivated in sterilized rice. For in vitro control, the antagonists isolates were matched with the pathogen in PDA medium, for the purpose of evaluating the reduction of growth and the hyperparasitism. For the biofumigations of the soil, the organic materials poultry litter, mussel, sugar cane bagasse, bean residue, cassava scuff were dehydrated in stove at 55ºC for 96h, grinded in the concentrations of 10% and 20% (v/v) and incorporated to the substrate, infested for 20 days and compared to the group treated with methyl thiophanate and to the control. After thirty days, the seedlings were evaluated about the incidence and the suppression of the disease. In the in vivo control the seeds were microbiolized with antagonists (C110, C21, ENF24, R14 and Trichoderma harzianum), the fungicide and saline solution for the control. The substrate was infested with the pathogen, two days after the sow, and after 30 days were evaluated. For the natural substances, 21 days old seedlings were pulverized with cassava flour wastewater extract (40%), eucalyptus oil (1%), peppermint (1%), Ecolife® (2%), methyl thiophanate (0,7 g/L) and water for the control and after two days, the substrate was infested with the pathogen. Six days after the inoculation, a new pulverization was done. The mineral fertilization was done in the sow trough Sarruge solution and doses of calcium silicate and sodium, 50, 100, 500 and 1000mg/L-1 and water for the control. The substrate was infested two days after that and a second fertilization was done 10 days after the sow. After 30 days the evaluations took place. The antagonists R14, C16, ENF 24 and T. harzianum inhibited the pathogen with RC from 42 up to 57%. Trichoderma has the hyperparasitic capacity. The incorporation of organic material was not efficient in the control of the disease. The in vivo antagonists reduced the incidence of the disease, but it was effective in the suppression. The oils and plant extracts were not efficient in reduced the incidence. The mineral fertilizations was not able to suppress the disease. / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O feijão-caupi, Vigna unguiculata (L.) Walp., é conhecido como feijão-de-corda e feijão-verde sendo uma das principais culturas exploradas pelos pequenos produtores no Nordeste brasileiro. Dentre os fitopatógenos que afetam sua produtividade, destaca-se Sclerotium rolfsii Sacc. que causa a podridão de colo em diversos cultivos do mundo. O objetivo do trabalho foi avaliar o controle alternativo de S. rolfsii Sacc. em mudas de V. unguiculata (L.) Walp. através do uso de antagonistas, incorporação de resíduos orgânicos ao solo, utilização de óleos essenciais, extratos vegetais e ecolife® e nutrição mineral. O trabalho foi desenvolvido no Laboratório de Fitopatologia e em casa de vegetação do CECA/UFAL. O patógeno foi obtido pelo isolamento de folhas de feijão-caupi com sintomas da doença e depois cultivados em arroz esterilizado. Para controle in vitro , os isolados de antagonistas foram pareados com o patógeno em meio de BDA, para avaliar a redução de crescimento micelial (RC) e o hiperparasitismo. Para a biofumigação do solo, as matérias orgânicas cama de frango, marisco, bagaço de cana, resíduo de feijão, raspa de mandioca foram desidratadas em estufa 55ºC por 96h, moídas e incorporadas ao substrato infestado, em concentrações de 10% e 20% (v/v) por 20 dias e comparadas ao tiofanato metílico e a testemunha. Após 30 dias, as plantas foram avaliadas quanto à incidência da doença e desenvolvimento da planta. No controle in vivo as sementes foram microbiolizadas com os antagonistas (C110, C21, ENF24, R14 e Trichoderma harzianum), o fungicida e água salina para testemunha. O substrato foi infestado com o patógeno, dois dias após o semeio foram avaliadas com 30 dias. Para as substâncias naturais, plantas de feijão-caupi, com 21 dias de idade foram pulverizadas com extrato de manipueira (40%), óleo de eucalipto (1%), hortelã pimenta (1%), Ecolife® (2%), tiofanato metílico (0,7 g/L) e água para a testemunha. Após dois dias, o substrato foi infestado com o patógeno. Ao completar seis dias da infestação, uma nova pulverização foi realizada. A adubação mineral foi realizada no semeio através de solução de Sarruge e doses de silicato de cálcio e sódio, 50, 100, 500 e 1000mg/L-1 e água para testemunha. O substrato foi infestado dois dias depois e uma segunda adubação foi feita 10 dias após o semeio. Os antagonistas R14, C16, ENF 24 e T. harzianum inibiram o patógeno com RC de 42 a 57%. Trichoderma teve capacidade hiperparasitária. A incorporação da matéria orgânica não foi eficiente no controle da doença. Os antagonistas in vivo reduziram a incidência da doença e contribuiu para o desenvolvimento das plantas. Os óleos e extratos vegetais não foram eficientes em reduzir a incidência da doença. A adubação mineral não foi capaz de suprimir a doença.
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Influência do Sistema Colinérgico na sensibilização ao efeito estimulante do etanol / Influence of the cholinergic system on ethanol-induced sensitizationTakahashi, Shirley [UNIFESP] 01 January 2006 (has links) (PDF)
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Previous issue date: 2006-01-01 / No processo da sensibilização comportamental, que se desenvolve a algumas drogas psicoativas, participam diversos sistemas de neurotransmissão, entre eles o sistema colinérgico, que modula de maneira importante o funcionamento de vias dopaminérgicas. Neste estudo avaliamos os efeitos da escopolamina, um antagonista colinérgico muscarínico, no desenvolvimento e expressão da sensibilização ao efeito estimulante do etanol (Estudo I) e os níveis de ligação dos receptores colinérgicos muscarínicos M1 em animais classificados como apresentando Alta (AS) ou Baixa Sensibilização (BS) ao efeito estimulante do etanol (Estudo II). No Estudo I, quatro grupos camundongos suíços albinos machos receberam durante 21 dias, respectivamente: salina+salina (sal/sal); 1,0 mg/kg de escopolamina+salina (escop/sal); salina+2,2 g/kg de etanol (sal/2,2EtOH) ou 1,0 mg/kg escopolamina+2,2 g/kg de etanol (escop/2,2EtOH). A atividade locomotora dos animais foi registrada por 20 minutos no 1°, 7°, 14° e 21° dias de tratamento. Agudamente, tanto etanol como escopolamina não alteraram a atividade locomotora dos animais, porém, a co-administração das duas drogas induziu um significativo efeito depressor, ao qual se desenvolveu tolerância com o tratamento. Apenas o grupo sal/2,2EtOH desenvolveu sensibilização. Após o tratamento foram realizados 3 desafios (28°, 31° e 34° dias), nos quais metade do grupo sal/sal recebeu salina e a outra metade recebeu a droga-desafio (etanol nos desafios 1 e 2 e escopolamina no desafio 3). Nos desafios 1 e 3, realizados nas caixas de atividade, somente os animais dos grupos sal/2,2EtOH e escop/2,2EtOH expressaram sensibilização, sugerindo "sensibilização cruzada" entre etanol e escopolamina. No desafio 2, realizado em um ambiente novo para eles (campo aberto), a expressão da sensibilização foi bloqueada. No Estudo II os camundongos foram tratados por 21 dias com salina ou 2,2 g/kg de etanol (i.p.), sendo estes classificados como AS ou BS, com base na atividade do 21° dia. Os animais foram sacrificados para análise auto-radiográfica da densidade de receptores M1, não tendo sido observadas diferenças significativas entre os animais classificados como AS, BS ou controles (salina), em nenhuma das 20 regiões encefálicas analisadas. Em resumo, a escopolamina influenciou o processo de sensibilização ao efeito estimulante do etanol, sugerindo que o sistema colinérgico é importante neste processo. Porém, as neuroadaptações que ocorreram com o tratamento crônico com etanol parecem não afetar os níveis de receptores M1. / Various neurotransmission systems have influence on the behavioral sensitization process developed after repeated administration of some drugs of abuse, among them the cholinergic system, which modulates the dopaminergic pathway’s functioning. In this study we evaluated the influence of scopolamine (an antagonist of cholinergic muscarinic receptors) on the development and _expression of behavioral sensitization to ethanol (Study I), as well as on the M1 binding, in animals classified as presenting high (AS) or low (BS) sensitization to ethanol (Study II). In Study I, four groups of male Swiss albino mice received one of the following during 21 days: saline+saline (sal/sal); 1.0 mg/kg of scopolamine+saline (escop/sal); salina+2.2 g/kg of ethanol (sal/2.2EtOH) or 1.0 mg/kg scopolamine+2.2 g/kg of ethanol (escop/2.2EtOH). Their locomotor activity was recorded during 20 minutes on the first, 7th, 14th and 21st days of treatment. Acutely, neither ethanol nor scopolamine altered their locomotor activity; however the co-administration of the both drugs induced a significant depressor effect to which tolerance was developed. Only the sal/2.2EtOH group developed sensitization. After the treatment, 3 challenge tests were carried out (on days 28th, 31st and 34th), in which half of the sal/sal group received saline and the other half received the challenge drug (ethanol in challenges 1 and 2 and scopolamine in challenge 3). In challenges 1 and 3 the animals were tested in activity cages and only the sal/2.2EtOH and escop/2.2EtOH groups expressed sensitization, suggesting there is cross-sensitization between ethanol and scopolamine. In challenge 2, which was conducted in a new environment (open-field arena), the _expression of the sensitization was blocked. In Study II, mice were treated during 21 days with saline or 2.2 g/kg ethanol (i.p.) and the ethanol treated mice were classified as AS or BS, according to their locomotor activity on day 21st. The animals were sacrificed and the bindings to M1 sites were examined by auto-radiographic analyses. No significant differences were found among groups (AS, BS and control) in any of the 20 brain regions analyzed. The present results suggest that scopolamine influences the process of sensitization to ethanol and that the cholinergic system participates in this process. However, the neuroadaptation that occurred after chronic ethanol treatment does not seem to change the binding to M1. / TEDE / BV UNIFESP: Teses e dissertações
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