@article{APS8311,
author = {Yong Liang and Xiu-mei Sun and Xiao-liang Wang},
title = {Properties of transient outward potassium current and inward rectifier potassium current in immature human atrial myocytes},
journal = {Acta Pharmacologica Sinica},
volume = {20},
number = {11},
year = {2016},
keywords = {},
abstract = {AIM: To study the properties of transient outward K+ current (Ito) and inward rectifier K+ current (IKl) in immature human heart.
METHODS: Ito and IKl were recorded using whole-cell patch-clamp technique in atrial myocytes isolated from 12 immature (aged from 6 months to 5 a) human hearts.
RESULTS: Ito was voltage-dependent, activated and inactivated rapidly. The IC50 (95% confidence limits) of 4-AP on Ito was 0.64 (0.48-0.87) mmol.L-1. 4-AP 1 mmol.L-1 shifted V1/2 of activation from (6.6 +/- 2.0) mV to (19.8 +/- 3.0) mV (n = 4-10, P < 0.01). 4-AP 0.3 mmol.L-1 changed V1/2 of inactivation from (-49 +/- 4) mV to (-61.4 +/- 2.1) mV (n = 3, P < 0.01), but there were no obvious influence on voltage-dependent activation of Ito (P > 0.05). At the same concentration, the recovery time constant (tau value) was prolonged from (108 +/- 16) ms to (220 +/- 67) ms (n = 3-12, P < 0.01). IKl was also voltage-dependent. Its reverse potential was -40 mV.
CONCLUSION: Both Ito and IKl are important K+ channel currents in immature human atrial myocytes. 4-AP can affect the inactivation and recovery of Ito at low concentration (0.3 mmol.L-1) and affect its activation at high concentration (1 mmol.L-1).},
issn = {1745-7254}, url = {http://www.chinaphar.com/article/view/8311}
}