Cloning and functional expression of a human orthologue of rat vanilloid receptor-1

Capsaicin, resiniferatoxin, protons or heat have been shown to activate an ion channel, termed the rat vanilloid receptor-1 (rVR1), originally isolate d by expression cloning for a capsaicin sensitive phenotype. Here we descri be the cloning of a human vanilloid receptor-1 (hVR1) cDNA containing a 251 7 bp open reading frame that encodes a protein with 92% homology to the rat vanilloid receptor-1. Oocytes or mammalian cells expressing this cDNA resp ond to capsaicin, pH and temperature by generating inward membrane currents . Mammalian cells transfected with human VR1 respond to capsaicin with an i ncrease in intracellular calcium. The human VR1 has a chromosomal location of 17p13 and is expressed in human dorsal root ganglia and also at low leve ls throughout a wide range of CNS and peripheral tissues. Together the sequ ence homology, similar expression profile and functional properties confirm that the cloned cDNA represents the human orthologue of rat VR1. (C) 2000 International Association for the Study of Pain. Published by Elsevier Scie nce B.V. All rights reserved.