Selective and direct inhibition of TRPC3 channels underlies biological activities of a pyrazole compound.
Canonical transient receptor potential (TRPC) channels control influxes of Ca(2+) and other cations that induce diverse cellular processes upon stimulation of plasma membrane receptors coupled to phospholipase C (PLC). Invention of subtype-specific inhibitors for TRPCs is crucial for distinction of respective TRPC channels that play particular physiological roles in native systems. Here, we identify a pyrazole compound (Pyr3), which selectively inhibits TRPC3 channels. Structure-function relationship studies of pyrazole compounds showed that the trichloroacrylic amide group is important for the TRPC3 selectivity of Pyr3. Electrophysiological and photoaffinity labeling experiments reveal a direct action of Pyr3 on the TRPC3 protein. In DT40 B lymphocytes, Pyr3 potently eliminated the Ca(2+) influx-dependent PLC translocation to the plasma membrane and late oscillatory phase of B cell receptor-induced Ca(2+) response. Moreover, Pyr3 attenuated activation of nuclear factor of activated T cells, a Ca(2+)-dependent transcription factor, and hypertrophic growth in rat neonatal cardiomyocytes, and in vivo pressure overload-induced cardiac hypertrophy in mice. These findings on important roles of native TRPC3 channels are strikingly consistent with previous genetic studies. Thus, the TRPC3-selective inhibitor Pyr3 is a powerful tool to study in vivo function of TRPC3, suggesting a pharmaceutical potential of Pyr3 in treatments of TRPC3-related diseases such as cardiac hypertrophy.
Kiyonaka
Shigeki
S
Laboratory of Molecular Biology, Laboratory of Bioorganic Chemistry, Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Kyoto 615-8510, Japan.
Kato
Kenta
K
Nishida
Motohiro
M
Mio
Kazuhiro
K
Numaga
Takuro
T
Sawaguchi
Yuichi
Y
Yoshida
Takashi
T
Wakamori
Minoru
M
Mori
Emiko
E
Numata
Tomohiro
T
Ishii
Masakazu
M
Takemoto
Hiroki
H
Ojida
Akio
A
Watanabe
Kenta
K
Uemura
Aya
A
Kurose
Hitoshi
H
Morii
Takashi
T
Kobayashi
Tsutomu
T
Sato
Yoji
Y
Sato
Chikara
C
Hamachi
Itaru
I
Mori
Yasuo
Y
D000577:Amides; D000818:Animals; D001402:B-Lymphocytes; D002118:Calcium / Q000378:metabolism; D002460:Cell Line; D006984:Hypertrophy / Q000188:drug therapy; D051379:Mice; D032383:Myocytes, Cardiac / Q000473:pathology; D050778:NFATC Transcription Factors / Q000187:drug effects / Q000378:metabolism; D021381:Protein Transport / Q000187:drug effects; D011720:Pyrazoles / Q000737:chemistry / Q000494:pharmacology*; D051381:Rats; D013329:Structure-Activity Relationship; D050052:TRPC Cation Channels / Q000037:antagonists & inhibitors*; D010738:Type C Phospholipases / Q000187:drug effects / Q000378:metabolism
D000577:Amides; D050778:NFATC Transcription Factors; D011720:Pyrazoles; D050052:TRPC Cation Channels; C104603:TRPC3 cation channel; C031280:pyrazole; D010738:Type C Phospholipases; D002118:Calcium