This study examined the contributions of different brain areas to several of the behavior effects of amphetamine. The drug was micro-injected into each of six discreet brain sites in rats and the effects on behavior were examined. Amphetamine's rewarding effects were studied using the conditioned place preference (CPP) paradigm. Animals that had received injections into the nucleus accumbens showed a CPP, suggesting a rewarding effect of the drug. No effect was produced by injections into the medial frontal cortex, medial or lateral parts of the caudate nucleus, amygdala or the region around the area postrema. A conditioned taste aversion (CTA) towards a flavour that had been paired with the drug was produced by injections into the region around the area postrema, but not from the other sites. Anorexia and adipsia were both producted only by injections into the nucleus accumbens and amygdala. In the open field, increased activity was produced by intra-accumbens amphetamine injections, with smaller effects from the medial frontal cortex and medial caudate. Stereotyped behavior was not produced by any intra-cranial injection. The CPP, anorexia, adipsia and increase in activity that were produced by the intra-accumbens injections were interpreted as suggesting that the drug had stimulated approach behavior towards all stimuli, as if they had all become rewarding. The observation of a CPP from the accumbens and a CTA from the region around the area postrema suggests that the rewarding and apparently aversive effects of systemically injected amphetamine result from actions of the drug on different neuroanatomical substrates. Other hypotheses of the behavioral function of the neural substrates of the observed effects are presented.

Thesis (MSc)--University of Stellenbosch, 2005. / Bibliography. Also available via the Internet.

Thesis (Ph. D.)--West Virginia University, 2008. / Title from document title page. Document formatted into pages; contains xi, 87 p. : ill. Vita. Includes abstract. Includes bibliographical references (p. 71-79).

Thesis (M.S.P.H.)--University of Michigan, 1938.

Proefschrift--Utrecht. / "Stellingen": [2] p. inserted. Summary in Dutch. Bibliography: p. 42.

Thesis (M.S.P.H.)--University of Michigan, 1938.

Proefschrift--Utrecht. / "Stellingen": [2] p. inserted. Summary in Dutch. Bibliography: p. 42.

Thesis (Ph. D.)--State University of New York at Binghamton, Dept. of Psychology, 2005. / Includes bibliographical references.

Thesis (Ph. D.)--State University of New York at Binghamton, Department of Systems Science and Industrial Engineering (Biosystem concentration), 2005. / Includes bibliographical references.

Orientador: Denise Vaz de Macedo / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-08T20:10:55Z (GMT). No. of bitstreams: 1 Hohl_Rodrigo_D.pdf: 822844 bytes, checksum: fd38d4c98d17c89e25fcfd09540ba103 (MD5) Previous issue date: 2007 / Resumo: O empirismo do treinamento pode levar a um desequilíbrio entre estímulo da atividade motora e tempo de recuperação do esforço. Como conseqüência o atleta pode experimentar um estado agudo de fadiga e queda de desempenho denominado de overreaching, revertido em poucos dias. A persistência desta situação de desequilíbrio pode levar a um quadro crônico de sensação de fadiga acompanhado de queda de desempenho denominado de síndrome do overtraining (OTS), que pode durar semanas ou meses. O objetivo deste trabalho foi padronizar um protocolo controlado e reprodutível de treinamento em ratos que contivesse um período de desequilíbrio entre o estímulo do exercício e o tempo de recuperação que gerasse queda de desempenho. Há duas formas de exercício em ratos amplamente utilizadas na literatura: a natação e a corrida em esteira. Os primeiros dois capítulos deste trabalho descrevem a padronização de um teste de desempenho em natação, reprodutível ao longo do crescimento animal, para ser utilizado em estudos longitudinais. Para isso, precisávamos considerar o empuxo sofrido pelo animal no meio líquido e validamos (Capítulo I) um aparato de medição de volume para animais vivos e conscientes (AMV). No capítulo II apresentamos os dados da comparação da reprodutibilidade de dois testes de desempenho até a exaustão na natação durante os cinco primeiros meses de vida dos ratos. Um teste com adição de cargas ajustadas de acordo com o porcentual da massa corporal (MC) e outro com cargas constantes (CC). Utilizando o AMV constatamos que a densidade dos animais não variava e, como conseqüência, o teste MC diminuía o tempo de exaustão conforme os ratos aumentavam a massa durante o crescimento, enquanto o teste CC mantinha o tempo de exaustão ao longo do tempo. Paralelamente, iniciamos os estudos com exercício em esteira. No Capítulo III apresentamos um protocolo de 11 semanas, onde o desequilíbrio entre exercício e recuperação foi determinado pelo aumento das sessões diárias nas três últimas semanas em 2, 3 e 4 vezes, com diminuição no tempo de recuperação entre elas. Selecionamos no final desse treinamento dois grupos de ratos, aqueles que apresentaram baixo desempenho (BD) e aqueles que apresentaram aumento ou manutenção do desempenho (AD). Embora ambos os grupos tenham apresentado uma diminuição da massa corporal durante o aumento da freqüência de treinamento, o grupo BD precisou de uma semana a mais de repouso para voltar a aumentar a massa, sem modificar o desempenho. No Capítulo IV comparamos quatro grupos de ratos obtidos desse protocolo (Controle (CO), Treinados (T), BD e AD) em análises no sangue (glutamina, glutamato, alanina e hemograma) e músculo (citrato sintase (CS), lactato desidrogenase e glicogênio). Comparando BD com T e AD observamos: (1) diminuição da concentração plasmática de glutamina e aumento na de glutamato, com valores semelhantes aos do grupo CO; (2) diminuição da capacidade oxidativa (CS) e manutenção dos estoques de glicogênio; (3) leucocitose. Em vista das diferenças encontrada entre os grupos BD e AD, concluímos que o protocolo de treinamento de indução de overreaching representa uma ferramenta metodológica importante, que pode auxiliar no desvendamento dos mecanismos causadores da queda de desempenho nos estados de overreaching/OTS / Abstract: The empirical training can lead to an imbalance between the motor activity stress and recovery. As consequence, the athlete can try an acute state of fatigue and performance decrement called overreaching, reverted in a few days. This continuous unbalance can lead to a chronic fatigue state called as overtraining syndrome (OTS), that may last weeks or months. Our goal was to standardize a controlled and reproducible training protocol in rats that contained an unbalance period between exercise stress and recovery with performance decrement. Two forms of exercise is widely used for rats training in literature: swimming and treadmill running. Chapters I and II describe an adequate standardization for workload in swimming tests when applied to longitudinal studies with sedentary rats. Therefore, considering the rats' buoyance, we validate (Chapter I) an apparatus for measuring conscientious living rat body volume (AMV). In chapter II, we evaluated two types of swimming tests with overload in sedentary rats: one with the load adjusted according to percentage of body weight (BW) and another one with constant load (CL) over time. Through the AMV, we found that the rats' density did not vary significantly, as consequence, MC test showed performance decrement as the rats had their mass increased, while CC test maintained performance along rats growth. In time, we initiate the studies with treadmill exercise. In Chapter III, we present an eleven weeks training protocol where the unbalance between exercise stress and recovery was determined by the increase of the daily sessions in 2, 3 and 4 times in the last three weeks, reducing the recovery time between sessions. We selected two groups of rats in the end of the training protocol, those that presented low performance (BD) and those that presented performance increase or maintenance (AD). Although both groups (AD and BD) showed corporal mass reduction during the increase of the daily frequency, BD group return to increase the mass one week later than AD group, without modifying the performance. In Chapter IV, we compare four groups of rats after the eleven weeks training protocol (Control (CO), Trained (T), AD and BD) in blood (glutamine, glutamate, alanine and hematological variables) and muscle analyses (citrate synthase (CS), lactate dehydrogenase and glycogen). Comparing BD with AD and T groups, we observe: (1) reduction of the glutamine plasma concentration and increase of glutamate, with similar CO values; (2) reduction of the oxidative capacity (CS) and maintenance of the glycogen stores; (3) leucocitosys. We conclude that the training protocol induces the rats to overreaching and it represents a relevant methodological tool in overreaching / OTS metabolical mechanisms research envolved in performance decrement / Doutorado / Fisiologia / Doutor em Biologia Funcional e Molecular