A series of rigid azetidenyl-based methamphetamine analogs were synthesized from commercially available N-Boc-azetidinone. The benzylideneazetidine analogs were prepared via a Wittig olefination via the ylides generated from the corresponding triphenylphosphonium benzylhalide salts. The substituted benzylazetidine analogs were synthesized from the corresponding benzylideneazetidienes via hydrogention over palladium and platinum catalysts. The benzylideneazetidine and benzyliazetidine analogs were evaluated at monoamine transporters as a part of preliminary structure-activity study for the development of novel monoamine transporter ligands. The binding affinities of the azetidine analogs were determined at dopamine (DAT) and serotonin (SERT) transporters in rat brain tissue preparations. The preliminary in vitro binding studies revealed that the rigid scaffold of the azetidine ring system was an effective substitution for the 2-aminopropyl group of methamphetamine and led to compounds with nanomolar binding affinity at dopamine and serotonin. In general, the benzylideneazetidine analogs were more potent than the corresponding benzylazetidine analogs. In addition, the azetidine analogs were more selective for the serotonin transporter than the dopamine transporter. The 3-(3,4-dichlorobenzylidene)azetidine (24m) was the most potent analog of the series with Ki values of 139 nM for SERT and 531 nM for DAT (DAT/SERT = 3.8).

O objetivo do presente estudo foi avaliar a participação do sistema glutamatérgico nos efeitos induzidos pela anfetamina em camundongos sensibilizados e desafiados com ovalbumina, através do tratamento prévio com MK-801, um antagonista de receptores glutamatérgicos NMDA. Em relação aos animais tratados apenas com anfetamina, observamos que o tratamento prévio com MK-801: 1) reverteu a diminuição no número de leucócitos totais bem como o número de eosinófilos e neutrófilos no lavado broncoalveolar (LBA); 2) reverteu a diminuição da porcentagem de expressão das moléculas L-selectina e ICAM-1 em granulócitos do LBA; 3) reverteu a diminuição das citocinas IL-10 e IL-13 no sobrenadante do LBA; 4) reverteu a diminuição na contração da traquéia; 5) reverteu a desgranulação de mastócitos pulmonares; 6) não alterou a produção de IgE total e IgE-OVA; 7) não reduziu os níveis de corticosterona plasmáticos. Tomados em seu conjunto, quer nos parecer que os efeitos induzidos pela anfetamina implicam na ativação do sistema glutamatérgico via receptores NMDA. Possivelmente, as diferenças dos efeitos do MK-801, da anfetamina ou a combinação de fármacos se devam a uma ativação (modulação) diferenciada sobre o eixo hipotálamo pituitária adrenal (HPA) e/ou sistema nervoso autônomo simpático (SNAS) o que poderia explicar os efeitos opostos observados na resposta inflamatória alérgica pulmonar de camundongos. / The aim of this study was to evaluate the involvement of the glutamatergic system in the effects induced by amphetamine in mice OVA-sensitized and challenged by the pretreatment with MK-801, an NMDA glutamate receptor antagonist. In relation to animals treated only with amphetamine we found that pretreatment with MK-801: 1) reverted the decrease in the total leukocytes and in the total number of eosinophils and neutrophils within the bronchoalveolar lavage fluid (BAL) 2) reverted the decrease in the percentage of expression of adhesion molecules L-selectin and ICAM-1 in BAL granulocytes, 3) reverted the decrease in IL-10 and IL-13 in BAL supernatant and 4) reverted the decrease in methacoline-induced tracheal contraction; 5) reverted the degranulation of mast cells in the lungs; 6) did not alter the production of total IgE and IgE-OVA, 7) did not decrease the plasma levels of corticosterone. Taken together, it seems feasible to suggest that the effects induced by amphetamine requires the participation of the glutamatergic system via NMDA receptors. Possibly, differences in MK-801, amphetamine or MK-801 + amphetamine effects on hypothalamic pituitary adrenal axis (HPA) and/or sympathetic autonomic nervous system (SNAS) might explain the opposite effects now observed for these drugs given alone or in combination in the pulmonary allergic inflammatory response in mice.

No mundo os acidentes de trânsito são responsáveis pela morte de aproximadamente 1,2 milhão de pessoas por ano. No Brasil, em 2014, foram mais de 44 mil óbitos no trânsito. O uso de substâncias psicoativas na direção é considerado um importante fator contribuinte para a ocorrência destes acidentes. Além do álcool, as drogas ilícitas mais utilizadas em nosso país são a anfetamina, a cocaína e a cannabis. As anfetaminas e a cocaína são utilizadas por motoristas de caminhão, que consomem para se manterem acordados por muitas horas e estão propensos a dormir ao volante. Portanto, há necessidade de conhecer o problema para que as autoridades competentes possam implementar políticas públicas relacionadas ao uso de drogas por motoristas e assim, minimizar os acidentes de trânsito no Brasil. Objetivo: Avaliar a prevalência do uso de substâncias psicoativas (anfetaminas, cocaína e cannabis) entre motoristas de caminhão que trafegavam em rodovias do Estado de São Paulo, através de análises toxicológicas em urina e correlacionar com dados sociodemográficos e ocupacionais. Métodos: Trata-se de estudo observacional do tipo transversal e a coleta dos dados foi realizada entre os anos de 2008 e 2012. Participaram do estudo 1.316 motoristas que, após assinarem o termo de consentimento livre e esclarecido e responderem a um questionário sobre dados sociodemográficos e ocupacionais, forneceram uma amostra de urina. Essas amostras foram analisadas por imunoensaio e por cromatografia em fase gasosa acoplada à espectrometria de massas. Resultados: Das amostras coletadas, 7,8% (n=103) apresentaram resultados positivos para uma ou mais drogas pesquisadas e/ou seus metabólitos, dos quais 3,4% foram resultados positivos para anfetamina, 2,8% para cocaína e 1,1% para cannabis. O 0,5% restante correspondeu aos casos com mais de uma droga. Com exceção do ano de 2008, as três drogas pesquisadas foram encontradas em todos os anos da pesquisa. Os resultados das análises toxicológicas se distribuíram de formas distintas de acordo com algumas variáveis: a idade, o tempo de profissão e o estado civil estiveram associados com o uso de drogas, enquanto o vínculo empregatício, a etnia e a escolaridade não apresentaram associação. Em relação à viagem, estiveram associados ao consumo de drogas a distância e o tempo de descanso noturno. O descanso diurno, o tempo total e o viajado, as horas de direção sem descanso, o número de ocupantes e o tipo de carga não apresentaram correlações significativas com o uso de drogas. Também não houve associação estatisticamente significante entre o consumo de drogas e doenças como hipertensão arterial, diabetes mellitus e estresse, nem com a prática de atividades físicas. Por outro lado, essa associação foi encontrada com o consumo de álcool, referido pelos caminhoneiros. Conclusão: os resultados indicam o uso de substâncias psicoativas por caminhoneiros e que este uso está associado com a idade, o tempo de profissão e o estado civil, assim como com a distância percorrida e o tempo de descanso noturno / Traffic accidents are responsible for approximately 1.2 million deaths per year worldwide. In Brazil, there were more than 44,000 traffic-related deaths in 2014. The use of psychoactive substances while driving is considered a major contributing factor to the occurrence of these accidents. In addition to alcohol, the most used illicit drugs in our country are amphetamines, cocaine and cannabis. Amphetamines and cocaine are commonly used by truck drivers to stay awake for several hours because they are likely to sleep while driving. Therefore, it is necessary to understand better this problem in order to help authorities implement public policies related to drug use by drivers and thus minimize traffic accidents in Brazil. Objective: To evaluate the prevalence of psychoactive substance (amphetamines, cocaine and cannabis) use among truck drivers in the highways of the State of Sao Paulo by toxicological analysis in urine and to correlate it with sociodemographic and occupational data. Methods: This is an observational cross-sectional study in which data collection was carried out between 2008 and 2012. This study included 1,316 drivers who provided a urine sample after signing a consent form and answering to a questionnaire with sociodemographic and occupational data. The urine samples were analyzed by immunoassay and gas chromatography-mass spectrometry. Results: Of the total samples collected, 7.8% (n = 103) were positive for one or more tested drugs and/or its metabolites, with 3.4% positive for amphetamine, 2.8% for cocaine and 1.1% for cannabis. The remaining 0.5% corresponded to cases with more than one drug. The three drugs were found during most of the study period, except in 2008. Toxicological findings were distributed differently according to some variables: age, employment period and marital status were associated with drug use, while the employment type, ethnicity and education were not. Travel length and night rest period were also associated with drug use. Daytime rest period, travel length period, driving time without rest, number of occupants and freight content did not correlate significantly with drug use. In addition, there was no statistically significant association between consumption of drugs and diseases (such as hypertension, diabetes and stress) or physical activity. However, the association between alcohol use (reported by truck drivers) and drug use was found. Conclusion: The results indicate that the use of psychoactive substances by truck drivers is common and this use is associated with age, employment period and marital status, as well as distance traveled and night rest period

Lisdexanfetamina (LDX) é um pró-fármaco estimulante de longa duração indicado para o tratamento dos sintomas do transtorno do déficit de atenção e hiperatividade e do transtorno da compulsão alimentar periódica. A hidrólise da ligação amida da LDX ocorre in vivo liberando a molécula terapeuticamente ativa d-anfetamina (d-ANF) e o aminoácido l-lisina. Visto que a LDX se biotransforma à d-ANF – um potente estimulante do sistema nervoso central com destaque tanto na clínica quanto na toxicologia – existe potencial para uso inadequado, abuso e desvio para fins não terapêuticos. Nos laboratórios de toxicologia, amostras biológicas com resultados positivos para anfetamina (ANF) são um desafio, uma vez que alguns testes toxicológicos podem detectar ANF devido à utilização de alguns medicamentos, dificultando a sua interpretação. Assim, são necessários métodos bioanalíticos eficientes aliados ao conhecimento farmacocinético, que permite a verificação da possibilidade de detecção, a estimativa da janela de detecção e as concentrações que podem ser alcançadas em diferentes matrizes biológicas. Dessa forma, neste trabalho, foram desenvolvidos métodos bioanalíticos para quantificação simultânea da LDX e de seu produto de biotransformação, a ANF, nas matrizes biológicas fluido oral, plasma e urina utilizando a cromatografia líquida acoplada a detector de massas sequencial (CL-EM/EM). A preparação de amostra é simples, utilizando a precipitação de proteínas para o plasma, com pouca quantidade de solvente orgânico, a diluição para o fluido oral e a filtração para urina, ambas com nenhuma quantidade de solvente orgânico. As curvas de calibração utilizando o padrão interno ANF deuterada apresentaram linearidade entre 1 e 128 ng/mL para o fluido oral e o plasma e entre 4 e 256 ng/mL para a urina. A menor concentração das curvas de calibração é igual ao limite inferior de quantificação. Precisão e exatidão intra e interdia ficaram dentro dos limites de ± 15% para os controles e ± 20% para o limite de quantificação. Os métodos foram seletivos e sem efeito residual, porém apresentaram um leve efeito matriz, frequentemente encontrado em métodos de CL-EM/EM. O método foi aplicado para análise das amostras do estudo farmacocinético da LDX e ANF nas matrizes biológicas fluido oral, plasma e urina após administração oral de LDX. Seis voluntários do sexo masculino coletaram amostras de fluido oral e plasma em tempos pré-determinados durante 72 horas e amostras de urina em intervalos pré-determinados durante 120 horas. Os dados foram avaliados de maneira não-compartimental e compartimental. Considerando a análise não-compartimental, a concentração máxima média da d-ANF foi quase seis vezes inferior no plasma em relação ao fluido oral e ocorreu em 3,8 e 4 horas, respectivamente, após a administração oral. A LDX atingiu a concentração máxima no plasma e no fluido oral em 1,2 e 1,8 horas após a administração oral, respectivamente, com um valor médio de pico de concentração quase duas vezes mais elevado no plasma em comparação com o fluido oral. A eliminação da d-ANF a partir do plasma e a partir do fluido oral foi semelhante, porém para LDX a eliminação a partir do fluido oral foi mais lenta, mesmo com concentrações mais baixas do que no plasma. A detecção da d-ANF ocorreu até 48-72 horas no plasma e fluido oral e até 120 horas em urina. Já para a LDX, a detecção ocorreu até 3, 5 e 12 horas no plasma, fluido oral e urina, respectivamente. LDX intacta e d-ANF foram detectadas nas três matrizes avaliadas. Na análise compartimental, o melhor ajuste de modelo foi observado para 1 compartimento para ambos os analitos tanto no plasma quanto no fluido oral. Houve uma correlação entre as concentrações do fluido oral e do plasma para d-ANF e entre as proporções de LDX intacta/d-ANF pelo tempo no plasma e no fluido oral. O método analítico desenvolvido pode ser aplicado em diferentes áreas do conhecimento a fim de certificar os resultados de uma análise de triagem positiva para ANF. Porém, para interpretação das situações tanto de triagem quanto de confirmação é necessário aliar o conhecimento farmacocinético gerado no trabalho, que demonstra se há a possibilidade de detecção na matriz analisada e por quanto tempo após a administração da LDX. Isto auxilia na diferenciação do uso de outros medicamentos derivados da ANF e do uso ilegal, para que as devidas providências legais e de manejos clínicos de tratamento e controle de dependência sejam tomadas quando necessário. / Lisdexamfetamine (LDX) is a long-acting prodrug stimulant indicated for the treatment of attention-deficit/hyperactivity disorder and binge-eating disorder symptoms. In vivo hydrolysis of lisdexamfetamine amide bond releases the therapeutically active d-amphetamine (d-AMPH) and the amino acid l-lysine. Since LDX biotransformation gives rise to d-AMPH - a potent stimulant of the central nervous system that stands out in clinical and toxicology - there is potential for misuse, abuse and diversion for non-therapeutic purposes. In laboratories of toxicology, biological samples with positive results for amphetamine (AMPH) are a challenge, since some toxicological tests can detect AMPH due to the use of some medications hindering the interpretation. Therefore, we need efficient bioanalytical methods combined with the pharmacokinetic knowledge, which allows to verify the possibility of detection, to assess the detection window and the concentrations that can be reached in different biological matrices. Hence, bioanalytical methods were developed for simultaneous quantification of LDX and its main biotransformation product AMPH in the biological matrices oral fluid, plasma and urine by liquid chromatography-mass spectrometry (LC-MS/MS). The sample preparation is simple, using protein precipitation for plasma, with a small amount of organic solvent, dilution for oral fluid and filtration to urine, both with no amount of organic solvent. Calibration curves using deuterated AMPH internal standard showed linearity between 1 and 128 ng/mL for oral fluid and plasma, and between 4 and 256 ng/mL for urine. The lowest concentration of the calibration curve is the lower limit of quantification. Intra and interday precision and accuracy were within the limits of ± 15% for controls and ± 20% for the limit of quantification. The methods were selective and no carry-over was observed, however with some matrix effect, often found in LC-MS/MS methods. The method was applied to analyze samples from LDX and AMPH pharmacokinetics study in the biological matrices oral fluid, plasma and urine following oral administration of LDX. Six male volunteers collected oral fluid and plasma samples at predetermined times during 72 hours and urine samples at pre-determined intervals during 120 hours. Data were evaluated through non-compartmental and compartmental analysis. Considering the noncompartmental analysis, the mean maximum concentration of d-AMPH was almost 6-fold lower in plasma than in oral fluid and occurred at 3.8 and 4 hours, respectively, after LDX administration. LDX maximum concentration was reached at 1.2 and 1.8 hours after LDX oral administration for oral fluid and plasma, respectively, with a mean peak concentration almost 2-fold higher in plasma when compared with oral fluid. Elimination of d-AMPH from oral fluid and from plasma were similar, albeit for LDX elimination from oral fluid was slower even with lower concentrations than plasma. Detection occurred until 48 to 72 hours in plasma and oral fluid and until 120 hours in urine for d-AMPH. Whereas for LDX, detection could be done for up to 3, 5 and 12 hours in plasma, oral fluid and urine, respectively. Intact LDX and d-AMPH were detected in the three evaluated matrices. In compartmental analysis, the best model fit was observed for 1-compartment model for both analytes in plasma and in oral fluid. There was a correlation between oral fluid and plasma d-AMPH concentrations and between intact LDX/d-AMPH ratios along time in plasma as well as in oral fluid. The bioanalytical methods developed can be applied in different fields of knowledge in order to ensure the results of a positive screening analysis for AMPH. Nevertheless, for interpretation of situations in both screening and confirmation tests is necessary to combine the pharmacokinetic knowledge produced in this study, which shows if there is the possibility of detection in the analyzed matrix and for how long after the administration of LDX. This results aid in the differentiation from other AMPH derived drugs use and from illegal use, so that appropriate legal action and clinical management strategies for treatments and control of dependence be taken when necessary.

O objetivo do presente estudo foi avaliar a participação do sistema glutamatérgico nos efeitos induzidos pela anfetamina em camundongos sensibilizados e desafiados com ovalbumina, através do tratamento prévio com MK-801, um antagonista de receptores glutamatérgicos NMDA. Em relação aos animais tratados apenas com anfetamina, observamos que o tratamento prévio com MK-801: 1) reverteu a diminuição no número de leucócitos totais bem como o número de eosinófilos e neutrófilos no lavado broncoalveolar (LBA); 2) reverteu a diminuição da porcentagem de expressão das moléculas L-selectina e ICAM-1 em granulócitos do LBA; 3) reverteu a diminuição das citocinas IL-10 e IL-13 no sobrenadante do LBA; 4) reverteu a diminuição na contração da traquéia; 5) reverteu a desgranulação de mastócitos pulmonares; 6) não alterou a produção de IgE total e IgE-OVA; 7) não reduziu os níveis de corticosterona plasmáticos. Tomados em seu conjunto, quer nos parecer que os efeitos induzidos pela anfetamina implicam na ativação do sistema glutamatérgico via receptores NMDA. Possivelmente, as diferenças dos efeitos do MK-801, da anfetamina ou a combinação de fármacos se devam a uma ativação (modulação) diferenciada sobre o eixo hipotálamo pituitária adrenal (HPA) e/ou sistema nervoso autônomo simpático (SNAS) o que poderia explicar os efeitos opostos observados na resposta inflamatória alérgica pulmonar de camundongos. / The aim of this study was to evaluate the involvement of the glutamatergic system in the effects induced by amphetamine in mice OVA-sensitized and challenged by the pretreatment with MK-801, an NMDA glutamate receptor antagonist. In relation to animals treated only with amphetamine we found that pretreatment with MK-801: 1) reverted the decrease in the total leukocytes and in the total number of eosinophils and neutrophils within the bronchoalveolar lavage fluid (BAL) 2) reverted the decrease in the percentage of expression of adhesion molecules L-selectin and ICAM-1 in BAL granulocytes, 3) reverted the decrease in IL-10 and IL-13 in BAL supernatant and 4) reverted the decrease in methacoline-induced tracheal contraction; 5) reverted the degranulation of mast cells in the lungs; 6) did not alter the production of total IgE and IgE-OVA, 7) did not decrease the plasma levels of corticosterone. Taken together, it seems feasible to suggest that the effects induced by amphetamine requires the participation of the glutamatergic system via NMDA receptors. Possibly, differences in MK-801, amphetamine or MK-801 + amphetamine effects on hypothalamic pituitary adrenal axis (HPA) and/or sympathetic autonomic nervous system (SNAS) might explain the opposite effects now observed for these drugs given alone or in combination in the pulmonary allergic inflammatory response in mice.

Increased demands on amphetamine dependence treatment services point to a need for effective pharmacotherapies for withdrawal symptom suppression. However, empirical data on which to base effective treatments are scarce. To address the need for an evidence base, four studies were conducted in two countries - Australia and Thailand. Firstly, the time course and severity of amphetamine withdrawal symptoms were characterised in two inpatient samples of amphetamine users. Results identified the first week of abstinence as an acute withdrawal phase characterised by increased sleeping, eating and a cluster of mood and anxiety - related symptoms. Following the acute phase, most withdrawal symptoms remained stable and at low levels for the remaining two weeks of abstinence ( the sub - acute phase ). Data from these two studies formed the basis for a new instrument, the Amphetamine Cessation Symptom Assessment scale ( ACSA ). On psychometric testing, the ACSA showed satisfactory reliability and a clear psychometric structure, delineating symptom clusters and their correlates with a three factor solution providing the best fit to the data. Using the ACSA to measure outcome, the safety and efficacy of the serotonin and noradrenaline reuptake inhibitor antidepressant mirtazapine ( 15 - 60 mg per day, n = 13 ), and the wake-promoting drug, modafinil ( 400mg per day, n = 14 ) were assessed in successive, open - label, inpatient pilot trials. Study medication was administered for up to ten days. An historical comparison group ( n = 22 ) who received treatment as usual consisting of pericyazine 2.5 - 10mg per day for control of agitation served as a comparison. Results showed that modafinil and mirtazapine were well tolerated, producing minimal positive subjective effects. There were significant group differences in withdrawal severity ( F = 18.6, df 2,219 p < 0.001 ). Post - hoc analysis showed that modafinil was more effective than mirtazapine ( p = 0.041 ), and both were more effective than treatment as usual ( both p < 0.001 ) in ameliorating withdrawal severity. Overall, these studies identified a peak in withdrawal severity during the first week of abstinence ; demonstrated the reliability and validity of the ACSA and identified modafinil as a safe and potentially effective pharmacotherapy for the treatment of amphetamine withdrawal symptoms. / Thesis (Ph.D.)--Medical School, 2005.

This study used the D2-preferring dopamine antagonist, haloperidol (3mg) and D1-D2 antagonist, fluphenazine (3mg) to investigate the roles of D1 and D2 receptors in d-amphetamine (20-mg) reinforcement in humans with (9 M; 7 F) and without (12 M; 4 F) an addictive disorder, in a placebo-controlled, between-within counterbalanced design. To preclude neurotoxicity, pathological gamblers served to evaluate effects of addiction status. Incentive motivation (e.g., Desire to Gamble), hedonic impact (e.g., Liking) and risky decision-making were assessed. Haloperidol reduced Desire to Gamble in controls, whereas fluphenazine reduced Desire in gamblers. Both antagonists reduced hedonic impact in both groups, with fluphenazine exhibiting stronger effects in gamblers. Both antagonists decreased risky decisions in controls but increased risky decisions in gamblers. Results suggest that D1 mediates amphetamine-induced motivation to gamble; D2 mediates amphetamine’s hedonic effects; D1 function is deficient in gamblers; and D2 blockade may reverse a restorative effect of amphetamine in addicted individuals.

This study used the D2-preferring dopamine antagonist, haloperidol (3mg) and D1-D2 antagonist, fluphenazine (3mg) to investigate the roles of D1 and D2 receptors in d-amphetamine (20-mg) reinforcement in humans with (9 M; 7 F) and without (12 M; 4 F) an addictive disorder, in a placebo-controlled, between-within counterbalanced design. To preclude neurotoxicity, pathological gamblers served to evaluate effects of addiction status. Incentive motivation (e.g., Desire to Gamble), hedonic impact (e.g., Liking) and risky decision-making were assessed. Haloperidol reduced Desire to Gamble in controls, whereas fluphenazine reduced Desire in gamblers. Both antagonists reduced hedonic impact in both groups, with fluphenazine exhibiting stronger effects in gamblers. Both antagonists decreased risky decisions in controls but increased risky decisions in gamblers. Results suggest that D1 mediates amphetamine-induced motivation to gamble; D2 mediates amphetamine’s hedonic effects; D1 function is deficient in gamblers; and D2 blockade may reverse a restorative effect of amphetamine in addicted individuals.

Rationale: Amphetamine abuse by adolescents predicts long-term drug dependence. Heightened vulnerability to drug abuse could be due to higher sensitivity to drug’s reinforcing effects. Rodents are used to study age-related sensitivities to drugs. Objective: We compared intravenous amphetamine self-administration between adolescent and adult male rats on an operant schedule of reinforcement measuring the reinforcing efficacy of a drug. Methods: After surgery, adolescent and adult rats acquired lever-pressing behavior reinforced by amphetamine infusions. Results: Both age groups exhibited more infusions per session as dose increased. However, neither the number of infusions per session nor total amphetamine intake differed across age groups. Conclusion: Although rapid transition is reliable to test reinforcing properties of stimulants, results suggest that amphetamine is an equally efficacious reinforcer among both age groups. In regards to humans, these results suggest that other factors, like social influences, explain higher rates of drug intake by adolescent compared with adult humans.

<p>Sex differences in drug addiction are mediated in part by effects of the ovarian hormone estradiol (E2) within the ascending dopamine (DA) system from the midbrain to the striatum. Estradiol enhances the effects of psychostimulants, but the exact underlying mechanisms are unknown. Mice could serve as an ideal genetically-tractable model for mechanistic studies into sex and hormone effects within the DA system but have been under-utilized. This study sought to: 1) characterize psychostimulant-induced behavior in mice as an indirect but quantifiable measure of DA neurotransmission, and 2) elucidate the mechanism underlying E2's enhancement of psychostimulant effects in females using surgical, pharmacological, and genetic manipulations. The spontaneous behavior of mice during habituation to a novel environment and after the psychostimulants d-amphetamine (AMPH; 1, 2.5, and/or 5 mg/kg) and cocaine (COC; 5, 15, and/or 30 mg/kg) were assessed in open field chambers using both automated photobeam interruptions and behavioral observations. Behaviors were assessed in the following groups of mice: intact males and females; ovariectomized mice replaced with either E2 for 2 days or 30 minutes or with estrogen receptor-selective agonists; and female mice lacking either ER&alpha; (&alpha;ERKO) or ER&beta; (&beta;ERKO) versus wildtype (WT) littermates. Brain psychostimulant concentrations and tissue content of DA and its metabolites were determined at the time of maximum behavioral stimulation. Psychostimulants induced behavioral activation in mice including both increased locomotion as detected with an automated system and a sequence of behaviors progressing from stereotyped sniffing at low doses to patterned locomotion and rearing at high doses. Intact female mice exhibited more patterned locomotion and a shift towards higher behavior scores after psychostimulants despite having lower AMPH and equivalent COC brain levels as males. Actively ovariectomized mice exhibited fewer ambulations and lower behavior scores during habituation and after psychostimulants than Sham females. Two days but not 30 minutes of E2 replacement restored COC-induced behavioral responses to Sham levels. ER&alpha;-selective PPT replacement in ovariectomized mice and genetic ablation of ER&alpha; in &alpha;ERKO mice altered COC-stimulated behavior. Immunohistochemistry revealed that midbrain DA neurons in mice express ER&beta; but not ER&alpha;, and that non-DA cells in the midbrain and the striatum express ER&alpha;. These results indicate that E2 enhances COC-stimulated locomotion in mice through an indirect effect of ER&alpha;. ER&alpha; may alter behavior through presynaptic effects on DA neuron activity and/or through postsynaptic effects on transcription and signal transduction pathways within striatal neurons.</p> / Dissertation