Penitrem A as a tool for understanding the role of large conductance Ca(2+)/voltage-sensitive K(+) channels in vascular function.

ABSTRACT: Large conductance, Ca(2+)/voltage-sensitive K(+) channels (BK channels) are well characterized, but their physiological roles, often determined through pharmacological manipulation, are less clear. Iberiotoxin is considered the "gold standard" antagonist, but cost and membrane-impermeability limit its usefulness. Economical and membrane-permeable alternatives could facilitate the study of BK channels. Thus, we characterized the effect of penitrem A, a tremorigenic mycotoxin, on BK channels and demonstrate its utility for studying vascular function in vitro and in vivo. Whole-cell currents from human embryonic kidney 293 cells transfected with hSlo α or α + β1 were blocked >95% by penitrem A (IC(50) 6.4 versus 64.4 nM; p < 0.05). Furthermore, penitrem A inhibited BK channels in inside-out a

SUBMITTER: Asano S 

PROVIDER: S-EPMC3400808 | biostudies-literature | 2012 Aug

REPOSITORIES: biostudies-literature