Alshuaib Waleed B, Mathew Mini V
Department of Physiology, Faculty of Medicine, Kuwait University, P.O. Box 24923, 13110, Safat, Kuwait.
Neurochem Res. 2005 Sep;30(9):1087-92. doi: 10.1007/s11064-005-7412-4.
The potassium A-current (IK(A)) is important in regulating the membrane potential between action potentials. The whole-cell patch-clamp technique was applied to cultured Drosophila neurons derived from embryonic neuroblasts. IK(A) was measured from neurons before and after application of 0.1 mM lanthanum to the external saline. IK(A) was smaller in the lanthanum-containing saline (7+/-1 pA) than in the control saline (34+/-6 pA). Activation and inactivation of IK(A) were unchanged by lanthanum. These results suggest that lanthanum neurotoxicity may lead to increased neuronal excitability. Moreover, given this inhibition of IK(A), lanthanum should not be used to block calcium current in studies of K+ currents.
钾离子A电流（IK(A)）在调节动作电位之间的膜电位方面很重要。全细胞膜片钳技术应用于源自胚胎神经母细胞的培养果蝇神经元。在向外部盐溶液中施加0.1 mM镧之前和之后，从神经元测量IK(A)。含镧盐溶液中的IK(A)（7±1 pA）比对照盐溶液中的（34±6 pA）小。镧对IK(A)的激活和失活没有影响。这些结果表明，镧的神经毒性可能导致神经元兴奋性增加。此外，鉴于对IK(A)的这种抑制作用，在钾离子电流研究中不应使用镧来阻断钙电流。
