Modulation of the NOP receptor signaling affects resilience to acute stress

Background: The peptide nociceptin/orphanin FQ (N/OFQ) and its receptor (NOP) are implicated in the modulation of emotional states. Previous human and rodent findings support NOP antagonists as antidepressants. However, the role played by the N/OFQ–NOP receptor system in resilience to stress is unclear. Aims: The present study investigated the effects of activation or blockade of NOP receptor signaling before exposure to acute stress. Methods: The behavioral effects of the administration before stress of the NOP agonists Ro 65-6570 (0.01–1 mg/kg) and MCOPPB (0.1–10 mg/kg), and the NOP antagonist SB-612111 (1–10 mg/kg) were assessed in mice exposed to inescapable electric footshock and forced swim as stressors. The behavioral phenotype of mice lacking the NOP receptor (NOP(-/-)) exposed to inescapable electric footshock was also investigated. Results: The activation of NOP receptor signaling with the agonists increased the percentage of mice developing helpless behavior and facilitated immobile posture. In contrast, the blockade of NOP receptor reduced the acquisition of depressive-like phenotypes, and similar resistance to develop helpless behaviors was observed in NOP(-/-) mice. Under the same stressful conditions, the antidepressant nortriptyline (20 mg/kg) did not change the acquisition of helpless behavior and immobile posture. Conclusions: These findings support the view that NOP activation during acute stress facilitates the development of depressive-related behaviors, whereas NOP blockade has a protective outcome. This study showed for first time that NOP antagonists are worthy of investigation as preemptive treatments in patients with severe risk factors for depression.

PENGARUH KUMULATIF ASAP ROKOK DAN STRES TERHADAP PENINGKATAN KADAR HORMON KORTISOL MENCIT

The aim of this study was to know the cumulative effect ofcigarette smoke and stress to the Cortisol hormoneincreasing of mice. The Observe was done to 36 malemices BALB/C, that were separated into 4 groups whichconsist of 9 mices per group, that groups were controlgroup, cigarette smoke group, electric foot shock group andcombine of cigarette smoke and electicfoot shockstress group. After they were given repeating andincreasing dose stressor during seven days, Cortisolhormone of mices were measured. The result of this studyshowed that combine of cigarette smoke and electric footshock stress group had increasing of Cortisol hormone washigher as significant difference (p<0.05) than controlgroups, cigarette smoke groups and electric foot shockgroup. Conclusion showed the cumulative effect ofcigarette smoke stressor and electric foot shock stressmore increasing Cortisol hormone of mice.

Evidence that behavioral depression does not influence airway cell influx in allergic rats

This study was designated to evaluate the influence of behavioral depression on the airway leukocyte recruitment in allergic animals. To achieve this, total and differential cell counts in bronchoalveolar (BAL) fluid of ovalbumin (OVA)-sensitized and depressed rats was evaluated. Inescapable electric footshock, applied on day 0, 7 and 13 after OVA sensitization, was used as a model to induce depression. In both non-depressed and depressed groups, the number of total and differential cells (eosinophils and mononuclear cells) in BAL fluid was significantly larger in sensitized compared with non-sensitized animals. However, no statistical differences were found between these groups with respect to the number of total and differential leukocytes,irrespective of the day inescapable shock was applied. Thus, behavioral depression does not influence the pattern of cell infiltration into the airways of allergen-induced airway inflammation.