Cruz J S, Matavel A C, Leão-Filho H M, Moraes-Santos T, Beirão P S
Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Caixa Postal 486, CEP 30161-970, Belo Horizonte, Minas, Gerais, Brazil.
Neurosci Lett. 2000 Mar 17;282(1-2):25-8. doi: 10.1016/s0304-3940(00)00862-4.
Previous studies have demonstrated that Li(+) ions can substitute for Na(+) in a variety of functional systems. Using the single sucrose-gap recording technique, we measured the nerve compound action potential to study the effects of tityustoxin (an alpha-scorpion toxin that selectively inhibits fast Na(+) channel inactivation) upon removal of extracellular Na(+). Our results suggest that tityustoxin requires the presence of extracellular Na(+) to produce its typical pharmacological effect on Na(+) channel inactivation kinetics, but not to bind to its site.
先前的研究表明，锂离子可以在多种功能系统中替代钠离子。我们使用单蔗糖间隙记录技术，通过测量神经复合动作电位，研究了在去除细胞外钠离子后，替尤斯毒素（一种选择性抑制快速钠离子通道失活的α-蝎毒素）的作用。我们的结果表明，替尤斯毒素需要细胞外钠离子的存在才能对钠离子通道失活动力学产生其典型的药理作用，但它与靶点的结合并不依赖细胞外钠离子。
