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Journal Article 2013; 34(5): 347-358 PubMed PMID: 23922038 Citation  Keywords:  Amygdala:drug effects, Animals, Association Learning:drug effects, Behavior, Animal:drug effects, Conditioning (Psychology):drug effects, Estrogen Receptor alpha:metabolism, Fear:drug effects, MAP Kinase Signaling System:drug effects, Male, Methyl-CpG-Bin.   

OBJECTIVES: Benzyl Butyl Phthalate (BBP) is an industrial plasticizer that has an unknown action in the central nervous system. Phthalates have recently been associated with behavioral actions that are linked to their endocrine disrupting properties. The purpose of this study was to investigate the behavioral and molecular effects of BBP treatment in male rats.

DESIGN: Male rats were chronically exposed to BBP in the drinking water (5.0 ppm and 10.0 ppm) throughout adolescence and into the adult phase of life. Their behavior was then assessed in a learning and memory task (fear conditioning), open field exploration and a test of sociability.

RESULTS: BBP treated rats showed decreased freezing in fear conditioning, no changes in open field exploration, and increased aberrant social behavior. Rats were sacrificed at post natal day 140 and blood and brains were harvested and processed. We found increased hormonally active estrogen, 17-β estradiol, in the serum of BBP treated rats. BBP treatment also induced changes in amygdalar proteins related to synaptic plasticity including decreased MeCP2 levels that correlated with tests of sociability with no changes in stress related proteins such as nuclear factor kappa B (NFkB). We also found alterations in physiological responses as measured by body weight without changes in food consumption suggesting disruption of metabolism and body homeostasis.

CONCLUSIONS: We suggest that BBP administration disrupts normal learning and social behavior, and that these effects could be related to alterations of amygdala function....

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Journal Article 2012; 33(7): 709-712 PubMed PMID: 23391882 Citation  Keywords:  Analgesics, Opioid:pharmacology, Animals, Behavior, Animal:drug effects, Choice Behavior:drug effects, Conditioning (Psychology):drug effects, Male, Mice, Morphine:pharmacology, Morphine Dependence:physiopathology, Music, Nucleus Accumbens:drug effects, R.   

OBJECTIVES: This research aims at studying the neuroendocrine effects of music on creating morphine dependence in mice using conditioned place preference (CPP).

METHODS: The mice treated with 10 mg/kg morphine subcutaneously, fast music and slow music. Morphine was used to create dependence. In order to recognize the morphine rewarding effects, CPP technique was used. In the conditioning stage that lasted for 8 days, different groups of mice, after receiving the treatment were randomly placed in compartment for 30 minutes. The post-conditioning stage included the fourth day, the ninth day, the 12th day and the 16th day.

RESULTS: Comparing place preference between morphine group and the control group, a significant increase (p<0.05) was observed in the place preference of morphine group, while a significant decrease (p<0.05) was demonstrated in the place preferences of morphine + taxi girl music group compared with morphine group alone. In addition morphine + alone in the rain music group demonstrated a significantly increased conditioned place preference (p<0.05) compared with the morphine group.

CONCLUSIONS: Alone in the rain music acts as a positive pleasant emotion increasing the dopaminergic activity in the Nucleus Accumbens (NAc) and Ventral Tegmental Area (VTA) and through associated learning mechanisms of reward-related behavior increases morphine addiction. However, taxi girl music may act as unpleasant experiences producing negative emotions and reducing morphine addiction....

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Journal Article 2011; 32(1): 90-95 PubMed PMID: 21407164 Citation  Keywords:  Adrenal Cortex Hormones:toxicity, Amygdala:drug effects, Animals, Avoidance Learning:drug effects, Behavior, Animal:drug effects, Brain:drug effects, Brain Stem:drug effects, Conditioning (Psychology):drug effects, Hippocampus:drug effects, Male, Prefront.   

BACKGROUND: Long term permanent changes of eating behavior and concomitant structural changes in the CNS are matter of debade in literature. Often there is not enough distinction beween acute and chronic exposure to corticoids in evaluating its effect on behavior and/or brain structural changes. For behavioral evaluation we used well established conditioned taste aversion (CTA) paradigm and coronal Nissl-stained brain sections for evaluation of neuroanatomical changes. The CTA is part of complex adaptive behavioral processes controling food intake. It is well established methodological tool for study of biological substrates of learning and memory.

AIM: Our hypothesis was that long term changes in laboratory rat behavior induced by exogenous corticosterone are not accompanyied by neurohistological changes in the rat brain, previously described in literature.

RESULTS: Firstly, our results support CTA paradigm as promising tool for testing chronic influence of stress hormones on eating behavior and memory. The results support fact that previous long term elevated corticosterone levels disrupt normal eating behavior and it could also lead to structural changes, which could be biological substrates of behavioral changes. The fact we have not found significant morphological changes in brain strengthen the notion of possible subcellular impairment taking place instead of simple neuronal loss....

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