Kobashi M, Bradley R M
Department of Biologic and Materials Sciences, School of Dentistry, University of Michigan, Ann Arbor 48109-078, USA.
Brain Res. 1998 Jan 19;781(1-2):218-26. doi: 10.1016/s0006-8993(97)01248-1.
Whole-cell current-clamp recordings were made from neurons in the rat parabrachial nucleus (PBN) in three rostro-caudal brain slices. During recording the neurons were located in one of four quadrants of the PBN. Successful recordings were obtained from neurons in three of these quadrants termed the dorsolateral (DL), dorsomedial (DM) and ventromedial (VM) quadrants. Recordings were made of the intrinsic membrane properties and repetitive discharge characteristics of 58 neurons in the DL, 60 neurons in the DM, and 54 neurons in the VM-quadrants. The input resistance of the neurons in the DL quadrant was significantly lower and the membrane time constant significantly shorter than that of the neurons in the DM- and VM-quadrants. The mean action potential duration of the VM-quadrant neurons was significantly longer than that of both DL- and DM-quadrant neurons. The discharge frequency in response to a 1500 ms 100 pA current pulse of the DL quadrant neurons was significantly lower than that of the neurons in the other two quadrants. The latency of action potential initiation following a 100 pA depolarizing current pulse was significantly longer for DL quadrant neurons compared to neurons in the other two quadrants. Neurons were divided into groups based on their response to a long depolarizing current pulse immediately preceded by a hyperpolarizing current pulse. In all three rostro-caudal slices of the PBN, the largest populations of neurons were in Group II and Group III. The results demonstrate that neurons in different locations in the PBN have different membrane and repetitive discharge properties. These different PBN locations receive inputs from the visceral and gustatory regions of the NST. It is possible therefore that the differences in properties of the PBN neurons may relate to the type of sensory information that they process.
在三个 rostro - caudal 脑切片中，对大鼠臂旁核（PBN）中的神经元进行全细胞电流钳记录。记录过程中，神经元位于 PBN 的四个象限之一。从被称为背外侧（DL）、背内侧（DM）和腹内侧（VM）象限的三个象限中的神经元获得了成功记录。对 DL 象限中的 58 个神经元、DM 象限中的 60 个神经元和 VM 象限中的 54 个神经元的内在膜特性和重复放电特性进行了记录。DL 象限中的神经元的输入电阻显著低于 DM 和 VM 象限中的神经元，且膜时间常数显著更短。VM 象限神经元的平均动作电位持续时间显著长于 DL 和 DM 象限的神经元。DL 象限神经元对 1500 ms 100 pA 电流脉冲的放电频率显著低于其他两个象限中的神经元。与其他两个象限中的神经元相比，DL 象限神经元在 100 pA 去极化电流脉冲后动作电位起始的潜伏期显著更长。根据神经元对紧接超极化电流脉冲之前的长去极化电流脉冲的反应将其分组。在 PBN 的所有三个 rostro - caudal 切片中，最大数量的神经元属于 II 组和 III 组。结果表明，PBN 中不同位置的神经元具有不同的膜特性和重复放电特性。这些不同的 PBN 位置接收来自 NST 的内脏和味觉区域的输入。因此，PBN 神经元特性的差异可能与它们处理的感觉信息类型有关。
