Center for Translational Neuroscience, Department of Neurobiology and Dev. Sci, University of Arkansas for Medical Sciences, 4301 W. Markham St., Slot 847, Little Rock, AR 72205, USA.
Pflugers Arch. 2013 Sep;465(9):1327-40. doi: 10.1007/s00424-013-1264-6. Epub 2013 Apr 16.
The parafascicular nucleus (Pf) is an ascending target of the pedunculopontine nucleus (PPN) and is part of the "non-specific" intralaminar thalamus. The PPN, part of the reticular activating system, is mainly involved in waking and rapid eye movement sleep. Gamma oscillations are evident in all Pf neurons and mediated by high threshold voltage-dependent N- and P/Q-type calcium channels. We tested the hypothesis that high-speed calcium imaging would reveal calcium-mediated oscillations in synchrony with patch clamp recorded oscillations during depolarizing current ramps. Patch-clamped 9 to 19-day-old rat Pf neurons (n = 148, dye filled n = 61, control n = 87) were filled with Fura 2, Bis Fura, or Oregon Green BAPTA-1. Calcium transients were generated during depolarizing current ramps and visualized with a high-speed, wide-field fluorescence imaging system. Cells manifested calcium transients with oscillations in both somatic and proximal dendrite fluorescence recordings. Fluorescent calcium transients were blocked with the nonspecific calcium channel blocker, cadmium, or the combination of ω-Agatoxin-IVA (AgA), a specific P/Q-type calcium channel blocker and ω-conotoxin-GVIA (CgTx), a specific N-type calcium channel blocker. We developed a viable methodology for studying high-speed oscillations without the use of multi-photon imaging systems.
束旁核（Pf）是被盖脚核（PPN）的上行投射靶区，也是“非特异性”丘脑板内核群的一部分。PPN 是网状激活系统的一部分，主要参与觉醒和快速眼动睡眠。所有 Pf 神经元都有明显的γ振荡，由高阈值电压依赖性 N 型和 P/Q 型钙通道介导。我们检验了这样一个假设，即高速钙成像将揭示钙介导的振荡与在去极化电流斜坡期间记录的膜片钳振荡同步。膜片钳钳制 9 至 19 天龄大鼠 Pf 神经元（n=148，染料填充 n=61，对照 n=87）用 Fura 2、Bis Fura 或 Oregon Green BAPTA-1 填充。在去极化电流斜坡期间产生钙瞬变，并使用高速宽场荧光成像系统进行可视化。细胞在体细胞和近端树突荧光记录中均表现出钙瞬变和振荡。非特异性钙通道阻断剂镉或特异性 P/Q 型钙通道阻断剂 ω-Agatoxin-IVA（AgA）和特异性 N 型钙通道阻断剂 ω-conotoxin-GVIA（CgTx）阻断荧光钙瞬变。我们开发了一种可行的方法，用于在不使用多光子成像系统的情况下研究高速振荡。
