resiniferatoxin and Chronic-Pain

The medicinal plant generally known as monkey's comb (Amphilophium crucigerum) has been popularly described for the treatment of neuropathic and inflammatory pain, specially seeds preparations.. The goal of the present study was to evaluate the antinociceptive effect of the crude extract (Crd) and dichloromethane fraction (Dcm) of A. crucigerum seeds, and investigate the involvement of transient receptor potential vanilloid 1 (TRPV1) receptor in this effect.. Male Swiss mice were used in this study. The effects of Crd and Dcm was tested on capsaicin-induced Ca. The oral administration of Crd or Dcm resulted in an antinociceptive effect in the hot water tail-flick (48°C) and capsaicin intraplantar tests. Furthermore, these preparations exhibited antinociceptive and anti-inflammatory effects in a chronic inflammatory pain model, and antinociceptive effects in a neuropathic pain model. Moreover, Crd and Dcm reduced capsaicin-induced Ca. In conclusion, our results support the analgesic effect of A. crucigerum and suggest the presence of compounds that may act as TRPV1 antagonists.

Topics: Analgesics; Animals; Bignoniaceae; Binding, Competitive; Calcium Signaling; Capsaicin; Chronic Pain; Disease Models, Animal; Diterpenes; Dose-Response Relationship, Drug; Ethanol; Male; Methylene Chloride; Mice; Neuralgia; Nociception; Nociceptive Pain; Pain Measurement; Phytotherapy; Plant Extracts; Plants, Medicinal; Protein Binding; Seeds; Signal Transduction; Solvents; Spinal Cord; Synaptosomes; TRPV Cation Channels