Toluene exposure enhances acute and chronic formalin-induced nociception in rats: Participation of 5-HT receptors.

The purpose of this study was to evaluate the effect of acute toluene exposure on formalin (0.5% and 1%)-induced acute and long-lasting nociceptive hypersensitivity in rats. In addition, we sought to investigate the role of peripheral 5-HT receptors in the pronociceptive effect of toluene.

Combination of diacerhein and antiepileptic drugs after local peripheral, and oral administration in the rat formalin test.

Preclinical Research The present study was designed to evaluate the possible antinociceptive interaction between diacerhein and some antiepileptic drugs (carbamazepine, topiramate and gabapentin) on formalin-induced nociception. Diacerhein, each of the antiepileptics or a fixed dose-ratio combination of these drugs was assessed after local peripheral and oral administration in rats. lsobolographic analyses were used to define the interaction between drugs.

Synergistic interaction between gabapentin and metamizol in the rat formalin test.

The purpose of this study was to assess the possible synergistic interaction between gabapentin and metamizol in the rat formalin test. Female Wistar rats were injected into the dorsal surface of the right hind paw with 50 microl of diluted formalin (1%). Formalin injection induced a typical flinching behavior indicating nociception.