Exacerbated sensitivity to mechanical stimuli that are normally innocuous or mildly painful (mechanical allodynia and hyperalgesia) occurs during inflammation and underlies painful diseases. Proteases that are generated during inflammation and disease cleave protease-activated receptor 2 (PAR2) on afferent nerves to cause mechanical hyperalgesia in the skin and intestine by unknown mechanisms. ...

UV-irradiation is a well-known translational pain model inducing local inflammation and primary hyperalgesia. The mediators and receptor proteins specifically contributing to mechanical or heat hyperalgesia are still unclear. Therefore, we irradiated buttock skin of humans (n = 16) with 5-fold MED of UV-C and assessed the time course of hyperalgesia and axon reflex erythema. In parallel, we too...

BACKGROUND Although opioids are unsurpassed analgesics for surgery, they also induce an N-methyl-D-aspartate-dependent enhancement of postoperative hyperalgesia. Because nitrous oxide (N2O) has anti-N-methyl-D-aspartate properties, the purpose of this study was to evaluate nitrous oxide ability to prevent such an opioid-induced hyperalgesia in rats. METHODS First, preventive effects of 50/50%...

BACKGROUND This study tests the hypothesis that loss of spinal activity of gamma-aminobutyric acid (GABA) contributes to the allodynia and hyperalgesia observed after peripheral nerve injury. METHODS Intrathecal catheters were implanted in male Sprague-Dawley rats. Antinociception was assessed by measuring withdrawal latency to immersion of the tail in a 52 degrees C water bath. Nerve injury ...

Remifentanil administration may subsequently cause paradoxical hyperalgesia in animals and humans, but mechanisms remain unclear. Manganese superoxide dismutase (MnSOD) nitration and inactivation caused by generation of reactive oxygen species and activation of N-methyl-D-aspartate (NMDA) receptors are involved in the induction and maintenance of central neuropathic pain. Hydrogen which selecti...

The anti-inflammatory and analgesic effects of the ethanolic extract (SLEE) and fruticulin A from the leaves of Salvia lachnostachys were evaluated in mice, using experimental models of inflammation (paw oedema and pleurisy induced by carrageenan injection) and hyperalgesia (electronic Von Frey). Oral administration of SLEE (30, 100, and 300 mg/kg) and fruticulin A (0.3 and 3.0 mg/kg) decreased...

Orphanin FQ/nociceptin (OFQ/N) and its receptor share substantial structural features and cellular actions with classic opioid peptides and receptors, but have distinct pharmacological profiles and behavioral effects. Currently there is an active debate about whether OFQ/N produces hyperalgesia or analgesia. Using a well-defined brainstem pain-modulating circuit, we show that OFQ/N can cause ei...

introduction: neuropathic pain may be due to a primary insult to the peripheral or central nervous system. in this situation, hyperalgesia and allodynia are the results of prostaglandins and cytokines release in the spinal cord. it seems that immune cells play an importat role in the induction and maintenance of chronic pain. compared to selective coxii inhibitors, nimesulide, a highly selectiv...

objective: to investigate the effect of intracerebroventricular injection of histamine on pain induced by subcutaneous iniection of formalin in the left ear of rabbit and the effect of the amine on morphine analgesia and naloxone hyperalgesia. design: experimental study. animals: sixty - six male new zealand white rabbits weighing 2.640.16kg. procedure: intracerebroventricular injections of the...

Due to the anti-diabetic and antioxidant activity of green tea epigallocatechin-gallate (EGCG), this research study was conducted to evaluate, for the first time, the efficacy of chronic treatment of EGCG on alleviation of hyperalgesia in streptozotocin-diabetic (STZ-diabetic) rats. Male Wistar rats were divided into control, diabetic, EGCG-treated-control and diabetic and sodium salicylate (SS...