No description available.

Psychostimulant-induced reinstatement of place preferences have been used to investigate underlying physiological mechanisms mediating drug-seeking behavior in adolescent and adult rodents; however, it is still unclear how psychostimulant exposure during adolescence affects neuronal communication in the mesolimbic dopamine (DA) pathway and whether these changes would elicit enhanced drug-seeking behavior later in adulthood. The aim of the present study was to investigate the effects of intra-ventral tegmental area (VTA) or intra-nucleus accumbens septi (NAcc) DA D2 receptor antagonist infusions on cocaine-induced reinstatement of cocaine place conditioning in high and low responders for cocaine reward. Adolescent rats were exposed to cocaine place conditioning [postnatal day (PND 28-39)] and divided into high and low responders for cocaine reward based on their place preference expression score. Place preferences were extinguished and guide cannula were implanted into either the VTA or NAcc followed by one of the following: 1) intra-VTA or intra-NAcc infusion of the DA D2 receptor antagonist sulpiride (100 µM) during a cocaine-primed reinstatement test (10 mg/kg/ip cocaine) or 2) measurement of NAcc DA levels during intra-VTA or intra-NAcc infusion of sulpiride (100 µM), a cocaine prime (10 mg/kg cocaine) and re-exposure to the cocaine paired chamber. Infusion of sulpiride into the VTA but not the NAcc blocked reinstatement of cocaine place conditioning in rats exposed to cocaine during adolescence. Furthermore, re-exposure to cocaine-associated cues and simultaneous local infusion of sulpiride into either the VTA or NAcc attenuated cocaine-induced increases in accumbal DA levels for rats pretreated with cocaine during adolescence, regardless of phenotype. These data suggest intrinsic compensatory mechanisms in the mesolimbic DA pathway mediate adolescent behavioral responsivity to cocaine prime-induced reinstatement of cocaine place conditioning later on in adulthood.

In humans, adolescent exposure to illicit drugs predicts the onset of adult drug abuse and suggests that early drug use potentiates adolescent vulnerability to drug addiction. In experiment 1, it was hypothesized that adolescent rats would show a CPP for a low cocaine dose if in fact adolescents are more vulnerable to cocaine's rewarding effects. Place preferences were measured in early adolescent [postnatal day (PND) 35], late adolescent (PND 45) and young adult (PND 60) rats by injecting either 0, 5 or 20 mg/kg cocaine and conditioning them to environmental cues in a 2-chamber place conditioning apparatus. Significant cocaine preferences were found for all ages at the high dose. Interestingly, PND 35's were the only age group to have a CPP at the low dose suggesting that PND 35 rats are more sensitive than late adolescent and young adult rats to cocaine's rewarding effects. In Experiment 2, it was hypothesized that age-related differences in cocaine CPP may be mediated by differences in the mesolimbic dopaminergic (DA) system throughout development. Extracellular DA levels in the nucleus accumbens septi (NAcc) of early adolescent, late adolescent and adult rats were measured via quantitative microdialysis. PND 35, PND 45 and PND 60 rats were injected daily with either 5 mg/kg/ip or saline for 4 days, surgically implanted with a microdialysis probe aimed at the NAcc. Rats were perfused with either 0, 1, 10 or 40 nM DA and the extracellular DA concentration was measured. Our results show that adolescents differ from adults in basal DA with PND 35 rats having low basal DA (0.4 nM), PND 45 rats having high basal DA (1.8 nM) and PND 60 rats having intermediate basal DA (1.3 nM). PND 45 cocaine treated rats showed a 58% decrease in basal DA. All cocaine treated rats, regardless of age, showed a significant increase in DA over baseline in response to a cocaine challenge. Additionally, there were age-related differences in the extraction fraction (Ed), an indirect measure of DA reuptake, with PND 45 and PND 60's showing a decrease in basal Ed, an effect absent in PND 35's. Together these findings suggest that there are substantial ontogenetic differences in extracellular DA and DA reuptake and that these differences may provide an explanation for adolescent vulnerability to addiction. Future research should investigate DA supply and degradation processes in naïve and cocaine treated adolescent rats and vulnerability to addiction.

Artificial divergent selection of chickens for high and low body weight at 8 weeks of age has produced two lines: the high (HWS) and low (LWS) body weight chicken lines. In addition to the difference in body weight, the lines show extreme differences in feeding behaviour and body composition. The aim of this study was to uncover the genetic and molecular factors that contribute to and determine these differences, especially regarding body energy regulation and appetite. In papers I and II, genome-wide gene expression in a brain sample containing hypothalamus and in dissected hypothalamus was analysed using DNA microarray and qRT-PCR. We found that levels of differential expression were generally moderate, which was consistent with the idea that polygenic factors were involved in the establishment of the chicken lines. Genes associated with neural plasticity, lipid metabolism and body energy regulation were differentially expressed. This result indicated that the neural systems regulating feeding behaviour and body weight were altered in the chicken lines. However, genes that were involved in the central melanocortin system were not systematically differentially expressed. Interestingly, the biggest differences in expression between the lines found in endogenous retrovirus sequences of the ALV subgroup E. Thus, in paper III, we characterized the number of integrations, the expression of ALVE retroviral elements and their effects on body weight. A significant correlation between low body weight and high ALVE expression was observed in female F9 birds from an HWS x LWS advanced intercross line. This implied that ev-loci contributing to increased ALVE expression levels were genetically linked to loci influencing the low body weight of the pullets. In paper IV, the carnitine palmitoyltransferase-1b gene (CPT1B), which was highly differentially expressed in the hypothalami, was investigated. We mapped chicken CPT1B to the distal tip of chromosome 1p. The levels of CPT1B mRNA in the HWS line were higher in the hypothalamus and lower in muscle than in the LWS line. This pattern of differential expression indicates that this gene could contribute to the remarkable phenotypic differences between HWS and LWS chickens. However, comparison with quantitative trait loci data showed that the expression of CPT1B is a trans effect, rather than a direct causative locus. In conclusion, the data suggested that the long-term selection for body weight resulted in differential gene expression in the brains of the selected chicken lines. These results may have relevance for the poultry industry and will also contribute to increasing knowledge about human diseases such as obesity and anorexia.

No description available.

Text in German / Die Arbeit ist eine ekklesiologisch-rnissiologische Untersuchung einer Migrantengruppe, der uber eine Viertelrnillion zahlender Russlanddeutscher, evangelisch freikirchlicher Tradition, die innerhalb von 35 Jahren, beginnend rnit 1963, als Aussiedler aus der vorrnaligen Sowjetunion in die Bundesrepublik Deutschland eingewandert sind. Die Aussiedlung und Einwanderung geschah in Absprache beider Staaten als Farnilienzusarnrnenfiihrung von Menschen deutscher Volkszugehorigkeit, die durch den zweiten Weltkrieg getrennt worden waren. Ethnisch ein Tei! von rund 1.900.000 Menschen, die oft nach vielen, anstrengenden aber entschlossenen Bernilhungen die Erlaubnis erlangten auszureisen. In Deutschland wurden sie unerwartet freundlich und hilfreich aufgenornrnen. Da keine offiziellen Angaben fiber die Anzahl der eingewanderten freikirchlichen Aussiedler vorliegen, war das erste Ziel der Studie, ihre zahlenrnaBige GroBe festzustellen. Ergebnis: Etwa 270.000 Personen sind als Farnilien der baptistischen und rnennonitischen Freikirche zuzurechnen. Von ihnen hatten sich rund 55.000 Erwachsene dern christlichen Glauben zugewandt und sich diesen Gerneinden angeschlossen. Die anderen waren Minderjahrige oder der Gerneinde bisher ferngeblieben. Erst nach der Aufnahrne in das Land ihrer Yater rnerkten viele, dass sie Frernde in der Heirnat waren. Wollten sie nicht Frernde bleiben, rnussten sie sich sozial, kulturell und kirchlich durch Anpassung integrieren. Dieser Prozess ist schwer, weil der einzelne Einwanderer sich dazu verandern rnuss. Zunachst aber wollen viele bleiben wie sie sind und so leben, wie sie in der alten Heirnat gelebt hatten. Besonders schwierig erweist sich die kirchliche Integration. Etwa sechs von sieben freikirchlichen Aussiedlern ( etwa 48.000) haben eigene Gerneinden gegrilndet, die anderen ( etwa 7 .000) haben ihre geistliche Heirnat in bestehenden Gerneinden gefunden. Diese neugegrilndeten Gerneinden weisen flir die BRD eine uberdurchschnittliche Wachsturnsrate auf. Ein zweites Anliegen ging der Frage nach, wie diese Gerneinden wachsen: Durch neuen Zuzug aus der GUS oder durch Bekehrung und Taufe? Ergebnis: Von den rund 62.000 Mitglieder (aus den ursprilnglichen 48.000) in Aussiedlereigenen Gerneinden (Stand 1998) sind rund 24.500 Glaubige in Verbindung rnit der Taufe zur Gerneinde gekornrnen. Die Zahl der Aussiedler-Taufen in den einheirnischen Gerneinden ist nicht bekannt. Drittens wurde diskutiert, inwiefern die Gerneinden ihre Lebensordnung bewahren und trotzdern ihren Missionsauftrag wahrnehrnen konnen. / The thesis is an ecclesio-missiological study of a migrant group of more than a quarter of a million Russian Germans, by tradition free church evangelicals. Beginning in 1963, they migrated from the former Soviet Union as 'Aussiedler' (re-settlers) to the Federal Republic of Germany. The resettling - agreed upon by both states - was a program of re-uniting families that had been separated during the Second World War. Ethnically, part of a larger group of 1,900.000 German people who, after exhausting but determined efforts, were permitted to leave for Germany. Here being welcomed and given generous material and social support. As no statistics about evangelical free church family immigrants are recorded, the first aim of the research was to establish their numerical size. The result:: By 1998 some 270,000 family members of this confession had entered Germany. Of these about 55,000 were adult Christian believers who had become members of a Baptist or a Mennonite Church. The rest were minors or adults with no confession of faith to date. In the country of their forbears many of the 'Aussiedler' realised: ,,We are strangers in our homeland. If we do not want to remain strangers, we need to adjust culturally, socially and religiously". Initially many resisted change. Change in to religious customs was particularly difficult. As a result, many did not join existing churches but established new congregations where they could practice their faith in the traditions familiar to them. Since the new 'Aussiedler' churches have been growing at an above average growth rate, the second goal was to investigate the reasons for this phenomenon. How much growth was by immigrantion? How much by conversion and baptism? It was found that of the ca. 62,000 members in the Aussiedler congregations (1998) ca. 24,500 had joined through baptism. The others had come in by immigration. A third area of discussion related to the question: In how far can immigrant Christians retain their own culture and still be faithful to their missionary calling? / Christian Spirituality, Church History and Missiology / D.Th. (Missiology)

Text in German / Die Arbeit ist eine ekklesiologisch-rnissiologische Untersuchung einer Migrantengruppe, der uber eine Viertelrnillion zahlender Russlanddeutscher, evangelisch freikirchlicher Tradition, die innerhalb von 35 Jahren, beginnend rnit 1963, als Aussiedler aus der vorrnaligen Sowjetunion in die Bundesrepublik Deutschland eingewandert sind. Die Aussiedlung und Einwanderung geschah in Absprache beider Staaten als Farnilienzusarnrnenfiihrung von Menschen deutscher Volkszugehorigkeit, die durch den zweiten Weltkrieg getrennt worden waren. Ethnisch ein Tei! von rund 1.900.000 Menschen, die oft nach vielen, anstrengenden aber entschlossenen Bernilhungen die Erlaubnis erlangten auszureisen. In Deutschland wurden sie unerwartet freundlich und hilfreich aufgenornrnen. Da keine offiziellen Angaben fiber die Anzahl der eingewanderten freikirchlichen Aussiedler vorliegen, war das erste Ziel der Studie, ihre zahlenrnaBige GroBe festzustellen. Ergebnis: Etwa 270.000 Personen sind als Farnilien der baptistischen und rnennonitischen Freikirche zuzurechnen. Von ihnen hatten sich rund 55.000 Erwachsene dern christlichen Glauben zugewandt und sich diesen Gerneinden angeschlossen. Die anderen waren Minderjahrige oder der Gerneinde bisher ferngeblieben. Erst nach der Aufnahrne in das Land ihrer Yater rnerkten viele, dass sie Frernde in der Heirnat waren. Wollten sie nicht Frernde bleiben, rnussten sie sich sozial, kulturell und kirchlich durch Anpassung integrieren. Dieser Prozess ist schwer, weil der einzelne Einwanderer sich dazu verandern rnuss. Zunachst aber wollen viele bleiben wie sie sind und so leben, wie sie in der alten Heirnat gelebt hatten. Besonders schwierig erweist sich die kirchliche Integration. Etwa sechs von sieben freikirchlichen Aussiedlern ( etwa 48.000) haben eigene Gerneinden gegrilndet, die anderen ( etwa 7 .000) haben ihre geistliche Heirnat in bestehenden Gerneinden gefunden. Diese neugegrilndeten Gerneinden weisen flir die BRD eine uberdurchschnittliche Wachsturnsrate auf. Ein zweites Anliegen ging der Frage nach, wie diese Gerneinden wachsen: Durch neuen Zuzug aus der GUS oder durch Bekehrung und Taufe? Ergebnis: Von den rund 62.000 Mitglieder (aus den ursprilnglichen 48.000) in Aussiedlereigenen Gerneinden (Stand 1998) sind rund 24.500 Glaubige in Verbindung rnit der Taufe zur Gerneinde gekornrnen. Die Zahl der Aussiedler-Taufen in den einheirnischen Gerneinden ist nicht bekannt. Drittens wurde diskutiert, inwiefern die Gerneinden ihre Lebensordnung bewahren und trotzdern ihren Missionsauftrag wahrnehrnen konnen. / The thesis is an ecclesio-missiological study of a migrant group of more than a quarter of a million Russian Germans, by tradition free church evangelicals. Beginning in 1963, they migrated from the former Soviet Union as 'Aussiedler' (re-settlers) to the Federal Republic of Germany. The resettling - agreed upon by both states - was a program of re-uniting families that had been separated during the Second World War. Ethnically, part of a larger group of 1,900.000 German people who, after exhausting but determined efforts, were permitted to leave for Germany. Here being welcomed and given generous material and social support. As no statistics about evangelical free church family immigrants are recorded, the first aim of the research was to establish their numerical size. The result:: By 1998 some 270,000 family members of this confession had entered Germany. Of these about 55,000 were adult Christian believers who had become members of a Baptist or a Mennonite Church. The rest were minors or adults with no confession of faith to date. In the country of their forbears many of the 'Aussiedler' realised: ,,We are strangers in our homeland. If we do not want to remain strangers, we need to adjust culturally, socially and religiously". Initially many resisted change. Change in to religious customs was particularly difficult. As a result, many did not join existing churches but established new congregations where they could practice their faith in the traditions familiar to them. Since the new 'Aussiedler' churches have been growing at an above average growth rate, the second goal was to investigate the reasons for this phenomenon. How much growth was by immigrantion? How much by conversion and baptism? It was found that of the ca. 62,000 members in the Aussiedler congregations (1998) ca. 24,500 had joined through baptism. The others had come in by immigration. A third area of discussion related to the question: In how far can immigrant Christians retain their own culture and still be faithful to their missionary calling? / Christian Spirituality, Church History and Missiology / D.Th. (Missiology)

No description available.