Analgesic properties of the novel amino acid, isovaline.

Background: Isovaline, a nonproteinogenic alpha-amino acid rarely found in the biosphere, is structurally similar to the inhibitory neurotransmitters glycine and gamma-aminobutyric acid. Because glycine(A) and gamma-aminobutyric acid receptor agonists are antiallodynic, we hypothesized that isovaline produces antinociception in mice.

Methods: All experiments were performed on female CD-1 mice using a blinded, randomized, and controlled design.

Effects of local tramadol administration on peripheral glutamate-induced nociceptive behaviour in mice.

Purpose: The use of peripheral tramadol to block pain has been advocated. However, since its actions in the periphery have not been elucidated fully, we tested the hypothesis that peripheral tramadol blocks peripheral glutamate-induced nociceptive behaviour in mice.

Methods: First, we compared the duration of paw licking after intraplantar (ipl.

QX-314 produces long-lasting local anesthesia modulated by transient receptor potential vanilloid receptors in mice.

Background: The quaternary lidocaine derivative QX-314 is now known to produce long-lasting local anesthesia despite its positive charge. However, recent research suggests that the transient receptor potential vanilloid receptor agonist, capsaicin, should reduce the onset and offset times, whereas the transient receptor potential vanilloid receptor antagonist, capsazepine, should delay the onset time of sensory blockade by QX-314.

Methods: Sensory blockade in the tail of the conscious mouse was investigated using QX-314 2.