en اثرات محرومیت غذایی بر رفتارهای دردی ناشی از فرمالین و غلظت بتااندورفین و هورمون های جنسی در موش های صحرایی Related Fields Related Fields مقاله کامل Full Length/Original Article Background: The present study examined the possible role of endogenous opioidergic system in effect of food deprivation on formalin-induced nociceptive behaviors in male and female rats. Also, we investigated the effect of food deprivation on the plasma level of beta-endorphin and sex hormones. Methods: Food was withdrawn 48 h prior to performing the formalin test, but water continued to be available ad libitum. The formalin was injected into hind plantar paw. Results: There is significant difference between male and female control rats during phase 2B. Following 48-h food deprivation, both male and female rats exhibited enhanced nociceptive behavior in response to formalin. Food deprivation for 12 and 24 h increased and for 48 h decreased beta-endorphin level in male and female rats. Food deprivation for 24 h decreased testosterone level in male, while it had no significant effect on female rats and food deprivation for 48 h decreased testosterone level in both sexes. Food deprivation for 24 h increased estradiol level in female and that for 48 h had no significant effect on male and female rats. Conclusions: The present study demonstrates the existence of food deprivation for 48 h causes enhancement of nociception in the formalin test in male and female rats that has correlation with decrease in plasma beta-endorphin and testosterone levels. Rat, Food Deprivation, beta-endorphin, Naloxone 107 113 http://ibj.pasteur.ac.ir/browse.php?a_code=A-10-1-515&slc_lang=en&sid=1 Mohammad-Reza Sarookhani محمدرضا ساروخانی No Elmira Ghasemi-Dashkhasan المیرا قاسمی No Nima Heidari-Oranjaghi نیما حیدری No Hassan Azhdari-Zarmehri حسن اژدری زرمهری hasan.azhdari@gmail.com Yes Elaheh Erami الهه ارمی No Sedighe-Sadat Hosseini صدیقه سادات حسینی No