Role of peripheral 5-HT, 5-HT and 5-HT receptors in the mechanical allodynia induced by serotonin in mice.

Serotonin (5-HT) acts as a neurotransmitter in the central nervous system (CNS) and as a mediator released by enterochromaffin cells to regulate intestinal motility. However, this amine also plays an important role as an inflammatory mediator and induces phenotypic changes of nociceptors. Despite the wide knowledge of the role of 5-HT in nociception, most studies have focused on its role in the CNS, while a clear information about its role in peripheral tissues is still lacking.

Activity of nicorandil, a nicotinamide derivative with a nitrate group, in the experimental model of pain induced by formaldehyde in mice.

Nicorandil (2-nicotinamide ethyl nitrate), an antianginal drug characterized by the coupling of nicotinamide with a nitric oxide (NO) donor, activates guanylyl cyclase and opens ATP-dependent K(+) channels. In the present study, we investigated the effects induced by per os (p.o.

Nicotinic acid induces antinociceptive and anti-inflammatory effects in different experimental models.

Although in vitro studies have shown that nicotinic acid inhibits some aspects of the inflammatory response, a reduced number of in vivo studies have investigated this activity. To the best of our knowledge, the effects induced by nicotinic acid in models of nociceptive and inflammatory pain are not known. Per os (p.

Antinociceptive and anti-inflammatory activities of nicotinamide and its isomers in different experimental models.

Although there is evidence for the anti-inflammatory activity of nicotinamide, there is no evaluation of its effects in models of nociceptive and inflammatory pain. In addition, there is no information about the potential anti-inflammatory and antinociceptive activities of the nicotinamide isomers, picolinamide and isonicotinamide. Per os (p.

Peripheral 5-HT1B and 5-HT2A receptors mediate the nociceptive response induced by 5-hydroxytryptamine in mice.

While the role of 5-hydroxytryptamine (5-HT, serotonin) in the nociceptive processing has been widely investigated in the central nervous system, information regarding its role in peripheral tissues is still lacking. Noteworthy, 5-HT induces phenotypic changes of nociceptors and peripheral injection induces pain in humans and nociceptive response in rodents. However, local receptors involved in 5-HT effects are not well characterized.

Effects induced by Apis mellifera venom and its components in experimental models of nociceptive and inflammatory pain.

The effects induced by Apis mellifera venom (AMV), melittin-free AMV, fraction with molecular mass < 10 kDa (F<₁₀) or melittin in nociceptive and inflammatory pain models in mice were investigated. Subcutaneous administration of AMV (2, 4 or 6 mg/kg) or melittin-free AMV (1, 2 or 4 mg/kg) into the dorsum of mice inhibited both phases of formaldehyde-induced nociception. However, F<₁₀ (2, 4 or 6 mg/kg) or melittin (2 or 3 mg/kg) inhibited only the second phase.

Antinociceptive and antiedematogenic activities of fenofibrate, an agonist of PPAR alpha, and pioglitazone, an agonist of PPAR gamma.

Peroxisome proliferator activated receptors (PPAR) are ligand-regulated transcription factors that control the expression of many genes. The antiinflammatory activity of fibrates, PPARalpha agonists, and thiazolidinediones, PPARgamma agonists, has been demonstrated in many in vitro and a few in vivo studies. In the present study, we evaluated the effect of acute (100 or 300 mg/kg, p.

Characterization of the antinociceptive and anti-inflammatory activities of riboflavin in different experimental models.

Riboflavin, similar to other vitamins of the B complex, presents anti-inflammatory activity but its full characterization has not yet been carried out. Therefore, we aimed to investigate the effect of this vitamin in different models of nociception, edema, fever and formation of fibrovascular tissue. Riboflavin (25, 50 or 100 mg/kg, i.

Antinociceptive, antiedematogenic and antiangiogenic effects of benzaldehyde semicarbazone.

Semicarbazones induce an anticonvulsant effect in different experimental models. As some anticonvulsant drugs also have anti-inflammatory activity, the effects of benzaldehyde semicarbazone (BS) on models of nociception, edema and angiogenesis were investigated. BS (10, 25 or 50 mg/kg, i.

Pharmacological investigation of the nociceptive response and edema induced by venom of the scorpion Tityus serrulatus.

In this study we characterized the nociceptive response and edema induced by the venom of the scorpion Tityus serrulatus in rats and mice and carried out a preliminary pharmacological investigation of the mechanisms involved in these responses. Intraplantar injection of the venom (1 or 10mug) induced edema and a marked ipsilateral nociceptive response, characterized by thermal and mechanical allodynia and paw licking behaviour. The nociceptive response was inhibited by previous intraperitoneal administration of indomethacin (4mg/kg), dipyrone (200mg/kg), cyproheptadine (10mg/kg) or morphine (5 or 10mg/kg), but not by dexamethasone (1 or 4mg/kg) or promethazine (1 or 5mg/kg).