The possible acute analgesic effect of pepper, tarragon, and chard in streptozotocin-diabetic rats using hot plate test



Diabetic rats in long-term display an augmented nociceptive response to thermal stimuli. Furthermore, hyperalgesia is one of the major symptoms of diabetic neuropathy in some patients. Considering the antidiabetic potential of medicinal plants chard, pepper, and tarragon, this study was undertaken to evaluate the possible analgesic effect of chard-, pepper-, and/or tarragon-mixed food intake in male streptozotocin-induced diabetic rats. For this purpose, male Wistar rats (n = 83) were randomly divided into control, treated controls, diabetic, and treated diabetic groups. At the end of the experiment, nociceptive response was evaluated using hot plate test. In this respect, the latency for the first response of the animal (either paw licking or jumping) was recorded as the pain response latency (PRL) in seconds. Meanwhile, only one determination was performed for each animal and 30 s of exposure with no response was established as the cut-off time. The results showed that although there was no significant reduction in PRL in diabetic rats as compared to control group, but pepper-treated diabetic rats have a significant higher PRL as compared to untreated-diabetic group (P<0.05). It can be concluded that oral administration of pepper for one month could attenuate the acute nociceptive response in diabetic rats.