@article{APS8714,
author = {Gang Wang and Ming-Xing Jiang and Mary D Coyne and Jose R Lemos},
title = {Comparison of effects of tetrandrine on ionic channels of isolated rat neurohypophysial terminals and Y1 mouse adrenocortical tumor cells},
journal = {Acta Pharmacologica Sinica},
volume = {14},
number = {2},
year = {2016},
keywords = {},
abstract = {The effects of tetrandrine on the voltage-gated Ca2+, K+, and Na+ channels of the isolated rat neurohypophysial nerve terminals and Y1 mouse adrenocortical tumor cells were studied using standard and perforated patch-clamp techniques. Among the inward ionic currents, the T-type Ca2+ channel current (I(Ca)) in the Y1 cell line was strongly inhibited (by 52.9%) by a low concentration (13 mumol.L-1) of externally applied tetrandrine. The L-type I(Ca) in the isolated nerve terminals was also strongly inhibited (by 54.2%) by externally applied tetrandrine 33 mumol.L-1, whereas the N-type I(Ca) and Na+ current were not significantly affected by the same dose of the alkaloid. While it had no effect on the fast, transient K+ channels, external application of tetrandrine 1 mumol.L-1 blocked a slowly-gating, maxi Ca(2+)-activated K+ (K+(Ca)) channel in the nerve terminals, decreasing its P(o) by 84.4%.CONCLUSIONS: (1) The order of the sensitivities of ionic channels to tetrandrine is K+(Ca) > T- > L- > N-type Ca2+ > Na+; (2) tetrandrine serves as a specific blocker of the slowly-gating K+(Ca) channel.},
issn = {1745-7254}, url = {http://www.chinaphar.com/article/view/8714}
}