The effect of Capsicum frutescens on formalin-induced flinching behavior in streptozotocin-diabetic rats



Diabetic rats in long-term display an augmented nociceptive response to chemical, mechanical, and thermal stimuli. Furthermore, hyperalgesia is one of the major symptoms of diabetic neuropathy in some patients. Considering the antidiabetic potential of pepper, this study was conducted to evaluate the possible analgesic effect of pepper-mixed food intake in male streptozotocin-induced diabetic rats. For this purpose, male Wistar rats (n = 46) were randomly divided into control, pepper-treated control, salicylate-treated control, diabetic, and pepper-treated diabetic groups. In this study, pepper was mixed with standard pelleted food. After one month, number of formalin-induced flinches/h was counted. The results showed that there was an increase in the number of flinches in both acute and chronic phases in diabetic rats (P<0.05), and administration of pepper for one month did significantly reduce the flinching behavior in both phases of the test (P<0.01). In contrast, sodium salicylate as positive control only reduced this score in the second phase. It can be concluded that oral administration of pepper through central and peripheral mechanisms could attenuate the nociceptive response in diabetic rats.