The endogenous lipid anandamide is a full agonist at the human vanilloid receptor (hVR1)

Br J Pharmacol. 2000 Jan;129(2):227-30. doi: 10.1038/sj.bjp.0703050.

Abstract

The endogenous cannabinoid anandamide was identified as an agonist for the recombinant human VR1 (hVR1) by screening a large array of bioactive substances using a FLIPR-based calcium assay. Further electrophysiological studies showed that anandamide (10 or 100 microM) and capsaicin (1 microM) produced similar inward currents in hVR1 transfected, but not in parental, HEK293 cells. These currents were abolished by capsazepine (1 microM). In the FLIPR anandamide and capsaicin were full agonists at hVR1, with pEC(50) values of 5. 94+/-0.06 (n=5) and 7.13+/-0.11 (n=8) respectively. The response to anandamide was inhibited by capsazepine (pK(B) of 7.40+/-0.02, n=6), but not by the cannabinoid receptor antagonists AM630 or AM281. Furthermore, pretreatment with capsaicin desensitized the anandamide-induced calcium response and vice versa. In conclusion, this study has demonstrated for the first time that anandamide acts as a full agonist at the human VR1.

MeSH terms

  • Arachidonic Acids / pharmacology*
  • Binding, Competitive / drug effects
  • Calcium / metabolism
  • Calcium Channels / drug effects
  • Calcium Channels / metabolism
  • Cannabinoids / pharmacology*
  • Capsaicin / pharmacology
  • Cell Line
  • Cloning, Molecular
  • Electrophysiology
  • Endocannabinoids
  • Ethanolamines
  • Humans
  • Hydrogen-Ion Concentration
  • Palmitic Acids / pharmacology
  • Patch-Clamp Techniques
  • Polyunsaturated Alkamides
  • Receptors, Drug / drug effects*
  • Recombinant Proteins / chemistry
  • TRPV Cation Channels

Substances

  • Arachidonic Acids
  • Calcium Channels
  • Cannabinoids
  • Endocannabinoids
  • Ethanolamines
  • Palmitic Acids
  • Polyunsaturated Alkamides
  • Receptors, Drug
  • Recombinant Proteins
  • TRPV Cation Channels
  • TRPV1 receptor
  • methanandamide
  • palmidrol
  • Capsaicin
  • Calcium
  • anandamide