Sensitization of vanilloid receptor involves an increase in the phosphorylated form of the channel.
A vanilloid receptor (VR1, now known as TRPV1) is an ion channel activated by vanilloids, including capsaicin (CAP) and resiniferatoxin (RTX), which are pungent ingredients of plants. Putative endogenous activators (anandamide and metabolites of arachidonic acid) are weak activators of VR1 compared to capsaicin and RTX, and the concentrations of the physiological condition of those activators are not sufficient to induce significant activation of VR1. One way to overcome the weak activation of endogenous activators would be the sensitization of VR1, with the phosphorylation of the channel being one possibility. The phosphorylation of VR1 by several kinases has been reported, mostly by indirect evidence. Here, using an in vivo phosphorylation method, the VR1 channel was shown to be sensitized by phosphorylation of the channel itself by multiple pathways involving PKA, PKC and acid. Also, in sensitizing VR1, BK appeared to show activation of PKC for the sensitization of VR1 by phosphorylation of the channel.
Lee
Soon-Youl
SY
Department of Genomic Engineering, Genetic Informatics Center, GRRC, Hankyong National University, Gyonggi 456-749 , Korea. sylee@hknu.ac.kr
Lee
Jae-Hag
JH
Kang
Kwon Kyoo
KK
Hwang
Sue-Yun
SY
Choi
Kang Duk
KD
Oh
Uhtaek
U
D000818:Animals; D001095:Arachidonic Acids / Q000494:pharmacology; D001920:Bradykinin / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism; D002211:Capsaicin / Q000494:pharmacology; D002460:Cell Line; D003001:Cloning, Molecular; D017868:Cyclic AMP-Dependent Protein Kinases / Q000378:metabolism; D004789:Enzyme Activation / Q000187:drug effects; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006801:Humans; D015640:Ion Channel Gating / Q000187:drug effects / Q000502:physiology*; D007473:Ion Channels / Q000378:metabolism*; D009865:Oocytes / Q000187:drug effects / Q000378:metabolism; D010766:Phosphorylation; D011493:Protein Kinase C / Q000378:metabolism; D051381:Rats; D011955:Receptors, Drug / Q000378:metabolism*; D014982:Xenopus laevis
D001095:Arachidonic Acids; D004791:Enzyme Inhibitors; D007473:Ion Channels; D011955:Receptors, Drug; D017868:Cyclic AMP-Dependent Protein Kinases; D011493:Protein Kinase C; D002211:Capsaicin; D001920:Bradykinin; D002118:Calcium