ABSTRACT
BACKGROUND: Menthol is the most important active material in mint and different mechanisms have been suggested for the way mint functions, most of which emphasize its analgesic effect owing to the presence of a group of temporary protein receptors. This study investigates the efficacy of peppermint capsule in the treatment of primary dysmenorrhea, in comparison with Mefenamic Acid and placebo. MATERIALS AND METHODS: This was a prospective, double-blinded, crossover study and was conducted on 127 girl students studying in Hamadan University of Medical Sciences who had experienced primary dysmenorrhea. Each participant was asked to take one of the drugs including Mefenamic Acid and Mint, starting from the first menstruation for 3 days. At the end of each period, a questionnaire was used to gather information; through the volunteer herself, pain intensity was recorded according to visual analog scale (VAS), duration of pain according to COX questionnaire, and bleeding amount according to pictorial blood loss assessment chart (PBAC) chart (Hygham). RESULTS: Average pain intensity and duration of pain were significantly lower after intake of Mefenamic Acid and Mint (P < 0.05). Average bleeding was significantly lower in those taking Mefenamic Acid capsule than in those taking peppermint extract (P < 0.05). Nausea and diarrhea were lower in the mint group than in Mefenamic Acid group. But analgesic usage was lower in Mefenamic Acid group than in peppermint group (P < 0.05). CONCLUSIONS: While the bleeding amount did not significantly change, pain and its severity and all the clinical signs and symptoms decreased after taking peppermint extract. Because the side effect of herbal drugs is lower than other medicinal drugs, using mint is advised for treating dysmenorrhea symptoms.
ABSTRACT
It has been shown that activation of type 1 orexinergic receptors (ORX1) in several parts of the hypothalamus stimulate food intake. Orexin A receptive sites for food intake exist primarily in a narrow band of the hypothalamus that is known to be involved in control of energy homeostasis. The present study aimed to investigate the role of orexin receptors in the medial preoptic area (MPOA) on food intake in rats. Twenty-four male rats weighing 200-250g were divided into three groups (n=8 in each group). Rats were cannulated using stereotaxic coordinates above the MPOA. Normal saline was microinjected into the MPOA in the control group. Another group received intra MPOA microinjection of SB334867, a selective antagonist for ORX1 receptors. In the other group, orexin A was microinjected (0.5µl of 1µmol) into the MPOA. Food intake was measured in metabolic cages. The statistical significance of differences between groups was detected by a one way ANOVA. A value of p<0.05 was considered significant. There was no significant difference in food consumption between saline and SB334867 treated groups. However, activation of the orexin receptor in the MPOA significantly increased food intake during the 2 and 8h after orexin A microinjection. Our results showed that during ad libitum access to food, activation but not blockade of the MPOA ORX1 receptor can increase food intake in a time-dependent manner. The role of these receptors in hunger and appetite stimulation requires further study.
