نعمت اله غیبی - Dept. of Biophysics, Qazvin University of Medical Sciences, Qazvin, Iran
محمد صوفی آبادی - Dept. of Physiology, Qazvin University of Medical Sciences, Qazvin, Iran
حسن اژدری زرمهری - Dept. of Physiology, Qazvin University of Medical Sciences, Qazvin, Iran
محمدحسین اسماعیلی - Dept. of Physiology, Qazvin University of Medical Sciences, Qazvin, Iran
شهرام رستاک - Faculty of Paramedical Sciences, Qazvin University of Medical Sciences, Qazvin, Iran
لیلا درگی - Faculty of Paramedical Sciences, Qazvin University of Medical Sciences, Qazvin, Iran
حمید رسول پور - Faculty of Paramedical Sciences, Qazvin University of Medical Sciences, Qazvin, Iran

Background and Objective: Amygdalin is likely to have analgesic and metabolic effects. In this study, the effects of chronic administration of amygdalin were investigated on the pain threshold, weight and blood sugar of mice. Materials and Methods: In this experimental study, formalin test was used as a chronic inflammatory model of pain. ۶۰ mice (۳۰-۳۵ g) were divided into four groups (n=۱۵) including: control and amygdalin ۱۰, ۲۵ and ۵۰ mg /kgw groups. Amygdalin was solved in saline and injected intraperitoneally every day at ۹-۱۰am. The control group received saline intraperitoneally for one week. After the last treatment, ۴۰µl formalin (۲.۵%) was injected to the right hind paw of the mice and pain symptoms (frequency of collecting flinching of the back skin and licking injection site) were recorded for ۶۰ min. Weight of the mice was measured before and after the last treatment with amygdalin. Blood glucose was also measured at the end of the experiment. Results were analyzed by using one way ANOVA and Tukey or paired t-test. Results: Intraperitoneal injection of ۱۰, ۲۵ and ۵۰ mg/kgw doses of amygdalin reduced pain in male mice. In concentration of ۵۰ mg/kg, not only the pain was completely inhibited but the animals’weight also decreased compared to pre-treatment period. Chronic injections of amygdalin had no impact on normal blood sugar levels. Conclusion: Chronic intraperitoneal injection of amygdalin increases pain threshold in mice and may also cause weight loss.

Keywords: Amygdalin, Formalin test, Pain, Mice