| 1. |
- Oreland, Sadia, et al.
(author)
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Does the transcription factor AP-2beta have an impact on the genetic and early environmental influence on ethanol consumption?
- 2010
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In: Journal of neural transmission. - : Springer Science and Business Media LLC. - 0300-9564 .- 1435-1463. ; 117:9, s. 1077-1081
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Journal article (peer-reviewed)abstract
- Genes involved in alcoholism have consensus sites for the transcription factor activator protein (TFAP) 2beta. In the present study, we investigated TFAP-2beta protein levels in the ethanol-preferring alko, alcohol (AA) and the ethanol-avoiding alko, non-alcohol (ANA) rat lines. Furthermore, basal and ethanol-induced TFAP-2beta levels were examined in Wistar rats exposed to different early postnatal environments that are known to affect later ethanol consumption. Taken together, we found differences in brainstem TFAP-2beta protein between the AA and ANA rats.
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| 2. |
- Oreland, Sadia, et al.
(author)
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Short- and long-term consequences of different early environmental conditions on central immunoreactive oxytocin and arginine vasopressin levels in male rats
- 2010
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In: Neuropeptides. - : Elsevier BV. - 0143-4179 .- 1532-2785. ; 44:5, s. 391-398
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Journal article (peer-reviewed)abstract
- Numerous studies have provided evidence for an important role for the neuropeptides oxytocin (OT) and arginine vasopressin (AVP) in establishment of social behaviour early in life, such as mother-pup interactions. However, there are few reports examining the consequences of early-life experiences on OT and AVP in male offspring. We have used the maternal separation (MS) model to study the effect of different early environmental conditions in rats. The purpose was to study OT and AVP in rats subjected to prolonged daily MS (360 min, MS360), short daily MS (15 min, MS15) and conventional animal facility rearing (AFR) during postnatal days 1-21. In addition, the influence of the presence or absence of littermates during MS, i.e. litter-wise (l) or individual (i) MS, was assessed. The immunoreactive (ir) peptide levels were measured in the hypothalamus, amygdala and pituitary gland of 3 and 10 weeks old male rats. Assessment in 3-week-old rats revealed that MS15 was associated with low ir OT levels in the hypothalamus and amygdala and high levels in the pituitary gland compared with the MS360 and AFR condition. In the amygdala, differences between groups were also detected in adulthood. MS studies commonly use either MS15 or AFR as a control for prolonged MS. The present results show differences in MS360 rats as compared to MS15 but not AFR rats. Consequently, comparisons between prolonged MS with either short periods of MS or AFR will generate divergent results, hence, making the outcome of MS difficult to compare between studies. Moreover, the different early environments had no effect on ir AVP levels. In conclusion, OT in the amygdala was most sensitive to MS. Besides both short- and long-term consequences, distinct effects were seen after litter and individual separation, respectively. We propose that environmentally induced alterations in OT transmission due to disrupted mother-pup interactions early in life may cause altered susceptibility to challenges later in life.
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| 3. |
- Salomé, Nicolas, et al.
(author)
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On the central mechanism underlying ghrelin's chronic pro-obesity effects in rats: new insights from studies exploiting a potent ghrelin receptor antagonist.
- 2009
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In: Journal of neuroendocrinology. - : Wiley. - 1365-2826 .- 0953-8194. ; 21:9, s. 777-85
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Journal article (peer-reviewed)abstract
- In the present study, we explore the central nervous system mechanism underlying the chronic central effects of ghrelin with respect to increasing body weight and body fat. Specifically, using a recently developed ghrelin receptor antagonist, GHS-R1A (JMV2959), we investigate the role of GHS-R1A in mediating the effects of ghrelin on energy balance and on hypothalamic gene expression. As expected, in adult male rats, chronic central treatment with ghrelin for 14 days, when compared to vehicle-treated control rats, resulted in an increased body weight, lean mass and fat mass (assessed by dual X-ray absorptiometry), dissected white fat pad weight, cumulative food intake, food efficiency, respiratory exchange ratio and a decrease of energy expenditure. Co-administration of the ghrelin receptor antagonist JMV2959 suppressed/blocked the majority of these effects, with the notable exception of ghrelin-induced food intake and food efficiency. The hypothesis emerging from these data, namely that GHS-R1A mediates the chronic effects of ghrelin on fat accumulation, at least partly independent of food intake, is discussed in light of the accompanying data regarding the hypothalamic genes coding for peptides and receptors involved in energy balance regulation, which were found to have altered expression in these studies.
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