Yu D, Feng C, Guo A
Laboratory of Visual Information Processing, Department of Neurobiology, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, People's Republic of China.
J Neurobiol. 1999 Aug;40(2):158-70. doi: 10.1002/(sici)1097-4695(199908)40:2<158::aid-neu3>3.0.co;2-#.
K(+) currents in cultured Drosophila larval neurons have been classified into four categories according to their inactivation time constants, relative amplitude, and response to K(+) channel blockers 4-AP and tetraethylammonium. The percentage (65%) of neurons displaying K(+) currents which were reduced to 30% in amplitude by 5 mM cyclic adenosine monophosphate (cAMP) analog 8-bromo-cAMP in both Drosophila memory mutants rutabaga (rut) and amnesiac (amn) was significantly larger than that (50%) in wild type. This initial characterization provides evidence for altered K(+) currents in both rut and amn mutants. Arachidonic acid, a specifical inhibitor of Kv4 family (shal) K(+) channels, was found to inhibit K(+) currents in cultured Drosophila neurons, suggesting the presence of shal channels in these neurons.
培养的果蝇幼虫神经元中的钾离子电流已根据其失活时间常数、相对幅度以及对钾离子通道阻滞剂4-氨基吡啶（4-AP）和四乙铵的反应分为四类。在果蝇记忆突变体rutabaga（rut）和失忆症（amn）中，5 mM环磷酸腺苷（cAMP）类似物8-溴-cAMP使显示钾离子电流的神经元百分比（65%），其电流幅度降低至30%，这一比例显著高于野生型中的比例（50%）。这一初步特征为rut和amn突变体中钾离子电流的改变提供了证据。花生四烯酸是Kv4家族（shal）钾离子通道的特异性抑制剂，它被发现可抑制培养的果蝇神经元中的钾离子电流，这表明这些神经元中存在shal通道。
