Neuroscience
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5-Hydroxymethylcytosine (5hmC) is abundant in the brain, suggesting an important role in epigenetic control of neuronal functions. In this paper, we show that 5hmC and 5-methylcytosine (5mC) levels are coordinately distributed in gene promoters of the rhesus macaque prefrontal cortex. ⋯ Furthermore, we found that early-life maternal deprivation is associated, in the adult monkey cortex, with DNA hydroxymethylation changes of promoters of genes related to neurological functions and psychological disorders. These results reveal that early social adversity triggers variations in brain DNA hydroxymethylation that could be detected in adulthood.
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Abnormalities of mental status represent a severe complication and an important cause of death in acute pancreatitis (AP), which is characterized by a pattern of neurological signs and symptoms. As some of the symptoms of AP are also affected by catecholamine neurotransmitters, they cannot be ruled out of the pathophysiology of AP; however, little research has been performed exploring this hypothesis. Our study aimed to elucidate whether AP affects the metabolism of catecholamine neurotransmitters in rats. ⋯ The MAO-A and TH protein concentrations of the 6-h and 24-h groups also decreased. The other catecholamine concentration and enzyme activities fluctuated, but there was no statistically significant difference compared with the control group. Catecholamine neurotransmitter metabolic systems are widely affected in AP, and these fluctuations may play an important role in determining the symptomatology of AP.
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Depression is a common symptom in Parkinson's disease (PD), but its pathophysiology remains unclear. Several lines of studies have revealed that the prelimbic (PrL) sub-region of the ventral medial prefrontal cortex and 5-HT1A receptors are involved in the regulation of depression. In this study, we examined whether complete unilateral lesions of the medial forebrain bundle (MFB) using 6-hydroxydopamine in rats are able to induce depressive-like behaviors, the role of PrL 5-HT1A receptors in the regulation of these behaviors, and co-localization of 5-HT1A receptor and neuronal glutamate transporter EAAC1-immunoreactive (EAAC1-ir) neurons in the PrL. ⋯ Furthermore, the intra-PrL injection of 5HT1A receptor antagonist WAY-100635 (60, 120, and 240ng/rat) showed a decrease in sucrose consumption, and an increase in immobility time, indicating the induction of depressive-like responses. However, the effective doses in the lesioned rats were higher than those in sham-operated rats, which attribute to down-regulation of 5-HT1A receptor expression on EAAC1-ir neurons in the PrL of the lesioned rats. These findings suggest that unilateral lesions of the MFB in rats may induce depressive-like behaviors, and 5-HT1A receptors of the PrL play an important role in the regulation of these behaviors.
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Apart from its role in regulating calcium there is growing evidence that vitamin D is a neuroactive steroid capable of regulating multiple pathways important for both brain development and mature brain function. Vitamin D induces its genomic effects through its nuclear receptor the vitamin D receptor (VDR). Although there is abundant evidence for this receptor's presence in the mammalian brain from studies employing immunohistochemistry, Western blot or quantitative RNA studies there remains some dispute regarding the validity of these studies. ⋯ In addition we have examined VDR subcellular distribution in the gut, kidney and brain from both embryonic and adult tissues. We show that in all embryonic tissues VDR distribution is mostly nuclear, however by adulthood it appears that at least in the gut and kidney, VDR presence in the plasma membrane is more prominent perhaps reflecting some change in VDR function with the maturation of these tissues. Finally the subcellular distribution of VDR in the embryo did not appear to be altered by vitamin D deficiency indicating that perhaps there are other mechanisms at play in vivo to stabilize this receptor in the absence of its ligand.
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Many marine fishes change sex in response to social cues when the dominance hierarchy is perturbed. Arginine-vasotocin (AVT) and the mammalian homolog arginine vasopressin are neuropeptides involved in social and reproductive behaviors across vertebrate taxa. The goal of this study was to determine whether AVT signaling influences aggression and expression of c-Fos, a marker of neuroplasticity, in key brain regions of the social decision circuit in Amphiprion ocellaris clownfish, a species where behavioral dominance precedes gonadal sex change from male to female. ⋯ Manning compound significantly reduced aggression and the probability of winning the contest relative to saline (vehicle) controls. In experiment 2, saline-treated fish displayed approximately twice as many c-Fos-positive cells in the POA and 25% more in the TPp than the Manning-treated fish, no differences were observed in the aTn. Taken together, results suggest AVT signaling is necessary for aggressive behavior and expression of neuroplasticity in the POA and TPp that likely contributes to behavioral dominance and hence, sex change in A. ocellaris.