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de Sousa Maciel, I.

Publications and source records attributed to de Sousa Maciel, I..

2 recordsLinked to original sources

Blockade of Kinin B1 receptor counteracts the depressive-like behavior and mechanical allodynia in ovariectomized mice

Menopause is related to a decline in ovarian estrogen production, affecting the perception of the somatosensory stimulus, changing the immune-inflammatory systems, and triggering depressive symptoms. Inhibition of kinin B1 and B2 receptors (B1R and B2R) inhibits the depressive-like behavior and mechanical allodynia induced by immune-inflammatory mediators in mice. However, there is no evidence on the role of kinin receptors in depressive-like and nociceptive behavior in female mice submitted to bilateral ovariectomy. This study shows that ovariectomized mice (OVX) developed time-related mechanical allodynia and increased immobility time in the tail suspension test (TST). The genetic deletion of B1R, or the pharmacological blockade by selective kinin B1R antagonist R-715 (acute, i.p), reduced the increase of immobility time and mechanical allodynia induced by ovariectomy. Neither genetic deletion nor pharmacological inhibition of B2R (HOE 140, i.p) prevented the behavioral changes elicited by OVX. Our data suggested a particular modulation of kinin B1R in the nociceptive and depressive-like behavior in ovariectomized mice. Selective inhibition of the B1R receptor may be a new pharmacological target for treating pain and depression symptoms in women on the perimenopause/menopause period.

animal behavior and cognition

Nitric Oxide Synthase inhibition counteracts the stress-induced DNA methyltransferase 3b expression in the hippocampus of rats

It has been postulated that activation of NMDA receptors (NMDAr) and nitric oxide (NO) production in the hippocampus is involved in the behavioral consequences of stress. Stress triggers NMDAr-induced calcium influx in limbic areas, such as the hippocampus, which in turn activates neuronal NO synthase (nNOS). Inhibition of nNOS or NMDAr activity can prevent stress-induced effects in animal models, but the molecular mechanisms behind this effect are still unclear. In this study, cultured hippocampal neurons treated with NMDA or dexamethasone showed increased of DNA methyltransferase 3b (DNMT3b) mRNA expression, which was blocked by pre-treatment with nNOS inhibitor n{omega}-propyl-L-arginine (NPA). In rats submitted to the Learned Helplessness paradigm (LH), we observed that inescapable stress increased of DNMT3b mRNA expression at 1h and 24h in the hippocampus. The NOS inhibitors 7-NI and aminoguanidine (AMG) decreased the number of escape failures in LH, and counteracted the changes in hippocampal DNMT3b mRNA induced in this behavioral paradigm. Altogether, our data suggest that NO produced in response to NMDAr activation following stress upregulates DNMT3b in the hippocampus.

pharmacology and toxicology