Bossu J L, Feltz A, Thomann J M
Pflugers Arch. 1985 Apr;403(4):360-8. doi: 10.1007/BF00589247.
The calcium currents of rat sensory neurones (of the IX and X cranial nerves) grown in culture were studied using whole cell recordings. In cells loaded with CsCl, and bathed in a solution where Na was replaced by choline or Tris, a step depolarization from -80 mV to 0 mV elicited the well-documented sustained Ca current (iCa,s). In contrast, depolarization from -80 mV to -60 mV and up to -20 mV evoked a distinct transient inward current (iCa,t) which could be isolated by imposing an internal pCa 7. It relaxed in about 100 ms and could possibly occur independently of the former current. The transient current was only affected by manipulation of the Ca concentration in the external medium and therefore was considered to be also a transfer of Ca. Ba was shown to act as a substitute with a lower affinity than Ca. The maximal amplitude of this current was in the order of a few hundred pA in Ca 5 mM and Mg 2 mM. Both activation and inactivation occurred in the same voltage span. The underlying event was studied using noise analysis and compared to the Ca transfer occurring during the sustained current as measured in chromaffin cells by Fenwick et al. (1982). We found them to be of similar amplitude.
使用全细胞记录法研究了培养的大鼠（IX和X颅神经）感觉神经元的钙电流。在加载CsCl并浸泡在Na被胆碱或Tris替代的溶液中的细胞中，从-80 mV到0 mV的阶跃去极化引发了记录充分的持续性钙电流（iCa,s）。相比之下，从-80 mV到-60 mV直至-20 mV的去极化引发了一种明显的瞬时内向电流（iCa,t），通过施加内部pCa 7可以将其分离出来。它在大约100毫秒内松弛，并且可能独立于前一种电流而发生。瞬时电流仅受外部介质中Ca浓度操作的影响，因此也被认为是Ca的转运。已表明Ba可作为替代物，但其亲和力低于Ca。在5 mM Ca和2 mM Mg中，该电流的最大幅度约为几百pA。激活和失活都发生在相同的电压范围内。使用噪声分析研究了潜在事件，并将其与Fenwick等人（1982年）在嗜铬细胞中测量的持续电流期间发生的Ca转运进行了比较。我们发现它们的幅度相似。
