introduction: different mechanisms are involved in stress induced analgesia (sia) and hyperalgesia (sih). repeated stress induces development of tolerance to sia. the role of hpa axis and gs signaling pathway in these effects are investigated in the current study. methods: forced swim stress (5 min/day) in water (20±1 ºc) was employed to adult male wistar rats (200-250 g). the nociceptive thres...

No animal models replicate the complexity of human depression. However, a number of behavioral tests in rodents are sensitive to antidepressants and may thus tap important underlying biological factors. Such models may also offer the best opportunity to discover novel treatments. Here, we used several of these models to test the hypothesis that the acid-sensing ion channel-1a (ASIC1a) might be ...

The novel antidepressant reboxetine is a selective norepinephrine reuptake inhibitor. In this study, the antidepressant-like effects of reboxetine were characterized in a modified rat forced swim test. Further, in order to investigate the role of the locus coeruleus and lateral tegmental noradrenergic systems in the mediation of reboxetine's effects, the impact of different chemical lesions of ...

To study anxiolytic and antidepressant effect of Astaxanthin as an adjuvant to standard drug.In this study, to investigate the effects of astaxanthin on anxiety and depression,we performed some behavioural trials including elevated plus maze test, hole-board test, forced swim test, and tail suspension test.Astaxanthin ( 3 mg/kg/day for 15 days, orally) significantly increased the time spent in ...

Background Stress constitutes a risk factor across several psychiatric disorders. Moreover, females are more susceptible to stress-related disorders, such as depression, than males. Although dopamine system underactivation is implicated in the pathophysiology of depression, little is known about the female dopamine system at baseline and post-stress. Methods The effects of chronic mild stress...

The opiate-receptor antagonist naloxone was administered to rats after passive-avoidance training either alone or in combination with forced-swim stress. A retention test revealed that while naloxone enhanced retention when administered alone, it impaired retention when administered in combination with forced-swim stress. The findings provide evidence for a "protective" endogenous opioid-based ...

The inability to learn an adaptive coping strategy in a novel stressful condition leads to dysfunctional stress coping, a marker of mental disturbances. This study tested the involvement of dorsal striatal dopamine receptors in the dysfunctional coping with the Forced Swim test fostered by a previous experience of reduced food availability. Adult male mice were submitted to a temporary (12 days...