Objective(s): There are many reports about the role of rostral ventromedial medulla (RVM) in modulating stress-induced analgesia (SIA). In the previous study we demonstrated that temporal inactivation of RVM by lidocaine potentiated stress-induced analgesia. In this study, we investigated the effect of permanent lesion of the RVM on SIA by using formalin test as a model of acute inflammatory pa...

OBJECTIVE Antinociceptive effect of morphine in offspring born of mothers that received saline or morphine during the gestation period was investigated. MATERIALS AND METHODS Wistar rats (200-250 g) received saline, morphine 0.5 mg/kg or 5 mg/kg during gestation days 14-16. All pups after weaning were isolated treatment/sex dependently and were allowed to fully mature. The antinociceptive eff...

AIM To observe effects of propofol on nociceptive response at superspinal and spinal level in rats. METHODS Two hundreds and fifty-eight Sprague-Dawley male rats were randomized into thirty-two groups. Propofol and bicuculline were microinjected into lateral ventricle (icv), ventrolateral periaqueductal gray (vlPAG), intrathecal (ith), and intraperitoneal (ip). The noxious responses were eval...

Introduction: Ginger has shown anti-nociceptive effects. Here we investigated the possible involvement of GABAA receptors in anti-nociceptive effect of ginger using muscimol (GABAA agonist) and picrotoxin (GABAA antagonist) in rats that received ginger. The pain sensitivity was evaluated by formalin test. Methods: Thirty-five male Sprague-Dawley rats were randomly divided into 7 groups (n=5): s...

Objective: Berberis vulgaris has antioxidant, hepato--renal protective, antibacterial, lipid lowering, anti-inflammatory and antinociceptive activities. The genus Berberis, has another member called Berberisintegerrima which has not been studied for antinociceptive activity and therefore, this study was aimed to examine the antinociceptive effect oftotal extract and alkaloid fractions of Berber...

Introduction: Uncoupling protein 2 (UCP2) in the inner mitochondrial membrane changes the activity of KATP channels and the cell excitability, probably by decreasing the ATP production. Given the expression of UCP2 in primary afferent neurons, and the importance of these channels in morphine-induced analgesia, genipin, an UCP2 inhibitor, may affect these processes, when administrated intrath...

Introduction: The formalin test is the most accepted chemical test for evaluation of nociception. It requires the injection of an adequate amount of formalin into the surface of the hindpaw. Formalin test consists of phase 1 (0-7 min) and phase 2 (15-60) in which the animal shows painful behaviors. These phases are separated with a quiet phase named interphase, in which the nociceptive respon...