title: Selective and direct inhibition of TRPC3 channels underlies biological activities of a pyrazole compound.
abstract: 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.
authors.affiliation: 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.
authors.forename: Shigeki
authors.initials: S
authors.lastname: Kiyonaka
authors.forename: Kenta
authors.initials: K
authors.lastname: Kato
authors.forename: Motohiro
authors.initials: M
authors.lastname: Nishida
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Mio
authors.forename: Takuro
authors.initials: T
authors.lastname: Numaga
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Sawaguchi
authors.forename: Takashi
authors.initials: T
authors.lastname: Yoshida
authors.forename: Minoru
authors.initials: M
authors.lastname: Wakamori
authors.forename: Emiko
authors.initials: E
authors.lastname: Mori
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Numata
authors.forename: Masakazu
authors.initials: M
authors.lastname: Ishii
authors.forename: Hiroki
authors.initials: H
authors.lastname: Takemoto
authors.forename: Akio
authors.initials: A
authors.lastname: Ojida
authors.forename: Kenta
authors.initials: K
authors.lastname: Watanabe
authors.forename: Aya
authors.initials: A
authors.lastname: Uemura
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Kurose
authors.forename: Takashi
authors.initials: T
authors.lastname: Morii
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Kobayashi
authors.forename: Yoji
authors.initials: Y
authors.lastname: Sato
authors.forename: Chikara
authors.initials: C
authors.lastname: Sato
authors.forename: Itaru
authors.initials: I
authors.lastname: Hamachi
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Mori
mesh_terms: 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
chemical_list: D000577:Amides; D050778:NFATC Transcription Factors; D011720:Pyrazoles; D050052:TRPC Cation Channels; C104603:TRPC3 cation channel; C031280:pyrazole; D010738:Type C Phospholipases; D002118:Calcium