Different duration of crowding and noise exposure effects on exploratory behavior, cellular immunity and HSP70 expression in rats

Abstract

This study examined the effects of different duration of stress exposure on cellular immunity and heat shock protein (HSP) 70 expression in rats. The different durations of crowding and noise were used as different stress modes. Observation of exploratory behavior in an open‐field test was used to indicate stress level. The expression of HSP70 and T‐cell subsets in blood samples were measured in the different groups of stressed rats. The results showed that there were significant reductions in the percentages of CD3+ and CD4+ T cells in the stressed groups. The lowest point was at 2 weeks from stress. There were significant increases in the percentage of CD8+ in 2 day, 1 week and 2 week stress groups compared with the control group. The CD4+/CD8+ ratio was also remarkably lower in rats of the 2 day, 1 week and 2 week stress groups compared with the control group. HSP70 expression rose significantly after stress and reached a maximum after 2 weeks of stress. Open field test activity showed higher vertical movement scores at 2 weeks stress compared with the control group. Grooming scores at 2 days stress was obviously more than that of the control and there were higher grooming scores at 2 weeks and 3 weeks stress compared to the 2 day stress group. Those results showed that the different duration stress exposure affects both exploratory behavior and immune function. The results also showed that not only immune function but also HSP70 expression was mainly dependent on the duration of stress. Copyright © 2006 John Wiley & Sons, Ltd.

Aircraft noise exposure affects rat behavior, plasma norepinephrine levels, and cell morphology of the temporal lobe

“…In addition, after suffering airport noise exposure for 8 d, rats of EG-II showed that the line crossing number decreased, which means horizontal mobility and exploration ability of the rat decreased and some anxiety appeared (Walsh and Cummins, 1976). However, Pan et al (2006) found that two weeks' noise stress (2 h/d, 85 dB) increased square crossing and vertical movement, which is in contrast to our results. There are a number of possible explanations.…”

Studies on Effects of Aircraft Noise on Behavior of Rats, Their Plasma Norepinephrine Levels and Cell Morphology of the Temporal Lobe

“…In addition, after suffering airport noise exposure for 8 d, rats of EG-II showed that the line crossing number decreased, which means horizontal mobility and exploration ability of the rat decreased and some anxiety appeared [13]. However, Pan et al found that two weeks' noise stress (2 h/d, 85 dB) increased square crossing and vertical movement, which is in contrast to our results [14]. There are a number of possible explanations.…”

Exposure of Hyperandrogen During Pregnancy Causes Depression- and Anxiety-Like Behaviors, and Reduced Hippocampal Neurogenesis in Rat Offspring

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