Background and aim: Stress is one of the most psychological disorders that can lead to many health problems, including vascular diseases of heart and brain, cancers and immunity suppression. Since it has been reported that there is a relationship between Stress and skin inflammation in one hand, and inflammation and scratching on the other hand, in the present study the effect of Immobilization Stress has been investigated on skin scratching.Methods: In this experimental study, 26 male rats were randomly divided into control and case groups. Stress was induced in the case animals, two hours daily for five days.After inducing Stress in each day, animals were observed for one hour and their scratching behavior was determined. The weight and scratching behavior were assessed before and 24 hour after the experiment. At the end of the examination, WBC counts were evaluated.Results: The mean frequency of scratching in days 1 and 2 was higher in the case group than the control group, but this difference was not found significant. However, in case group, mean frequency of scratching was significantly higher on day 3 (P<0.05), day 4 (P<0.01) and day 5 (P<0.001) compared to the control group.Conclusion: Our data showed that Immobilization Stress may lead to increase in skin scratching.

Background & aim: Arginine by regulating the biological activity of the brain plays an important role in reducing Stress. Today's, Stress is one of the century disease that created many problem. This study conducted to determine the protective effect of arginine on nitric oxide levels in maternal fetal brain tissue under Stress.Methods: Twenty pregnant Wistar rats (200-250 gr) were randomly divided into four groups. With and without Stress groups received arginine (200 mg/kg) intraperitoneal from 5-20 days of pregnancies. Control with and sham without Stress received 2 ml of normal saline. The pregnant rats were anesthetized by ketamine (100 mg/kg) on the day 20 then the fetuses removed and weighed. Twenty five brain of fetal brain rat from each group were chosen for measuring of forebrain thickness and brain volume. Another 25 brain were chosen for measuring of nitric oxide. Data were analyzed by one way ANOVA.Results: Nitric oxide Levels reduced in Stress rats treated with arginine compared to control group (P<0.05). The mean thickness of forebrain and hippicampal formation decreased in Stress rats versus unStressed, but was not significant. The mean weight decreased significantly in Stress group compared to the unStressed group (P<0.05).Conclusions: Arginine could protect the brain tissue and fetal weight by reducing the level of oxidative Stress in the pregnant rats.

Immobilization Stress as a physical and psychological Stress, has adverse effects on various body tissues. Numerous studies have been conducted on the effects of Stress on reproductive system and fertility. The Main aim of this study is evaluation of effect of Immobilization Stress on epididymal tissue in mice. In this study 140 adult male mice were randomly divided in to 7 groups as test and 7 groups as control animals. In test groups, the animals were subjected to Immobilization Stress for 1, 3, 7, 15, 30 and 60 days respectively. In control groups, the animals were only handled. After the experimental periods, blood samples were collected for measurements of serum cortisol and testosterone and epididymal tissue samples were obtained for histologic and histomorphometric study. The results of this study showed that level of testostrone in all test groups significantly decreased in comparison to the control groups (p<0.05). Cortisol level in test group at 1, 3, 7, and 15 days significantly increased (p<0.05) and in other groups no significant difference was observed. Histological study showed that in groups which were Stressed for 30, 45 and 60 days, in head, body and tail of epididym, diameter of tubules were decreased and interstitial tissue significantly increased (p<0.05). thickness of epithelium in head and body of epididym and in the tail region significantly decreased (p<0.05) in groups which were under Stress for 15, 30, 45 and 60 days and 30, 45 and 60 days respectively (p<0.05). Result of this study confirmed adverse effect of Immobilization Stress on epididymal tissue with increase in time of Stress, side effects also increases.

Background and purpose: Sleep and Stress are linked in a bidirectional manner. Immobilization Stress is a simple model that could be used easily in animal studies for understanding the neurobiology of Stress-sleep relationship. Cinnamaldehyde as a herbal medicine with antioxidant activities could be investigated in modulating sleep-Stress interaction. Materials and methods: In the present study, we examined the effects of Immobilization Stress combined with physical Stress on sleep stages in male Wistar rats. Sleep stages were evaluated through EEG and EMG signals before and after Stress induction during three consecutive days. The rats received Cinnamaldehyde orally by gavage at the dose level of 20 mg/kg/day. The treatment was started one week before surgery and lasted for 18 days. Results: Findings showed that Immobilization Stress decreased the rapid eye movement (REM) sleep (P= 0. 01). In the Stress exposed group treated with Cinnamaldehyde not only there were no decrease in REM sleep but also there were increase in REM and non-rapid eye movement (NREM) sleep. Conclusion: Cinnamaldehyde could improve sleep and repair REM sleep disturbance induced by Stress.

Background and Objective: Hydroalcholic extract of Peppermint is traditionally used for gastrointestinal disorders. This study was done to evaluate the effect of Peppermint extract on the mice colon motor activity following Immobilization Stress.Methods: In this experimental study, 30 male Albino mice were randomly allocated into the three groups; including control, Stress and Stress+Peppermint oil groups (n=10). The second group as a Stress group exposed to Immobilization Stress for four hours during three days. Third group as Stress plus Peppermintoil group was exposed to Stress in addition to administration of 27 mg/kg/bw Peppermint oil intraperitoneally prior to Stress. After three days, intestinal and peristaltic activity was recorded using pressure transducer from in vitro segments of colon (4-5 cm in length. Also, fecal weight, food intake and body weight was measured for each mouse for in vivo condition.Results: The mean±SD of fecal weight after three times Stress Immobilization was 1.36±0.71, 1.06±0.6 and 0.47±0.39 gr in control, Stress and Stress+Peppermint oil groups, respectively (P<0.05). The mean±SD of internal luminal pressure after three times Stress Immobilization was 4.47±1.15, 3.48±1.25 and 0.77±0.37 mm/hg in control, Stress and Stress+Peppermint oil groups, respectively (P<0.05).Conclusion: Peppermint oil is a strong inhibitor for colon motor activity following Immobilization Stress.