Tsutsumi T, Isogawa K, Kouno Y, Hikichi T, Nagayama H, Akiyoshi J
Department of Neuropsychiatry, Oita Medical University, Japan.
Nihon Shinkei Seishin Yakurigaku Zasshi. 1998 Feb;18(1):15-8.
The aim of this study is to determine whether or not CCKB receptor antagonist PD135158 suppresses conditioned fear. Rats were individually subjected to 30 min of inescapable electric footshock in a chamber with a grid floor. PD135158 or the vehicle was administered 30 min before placing the rats in the shock chamber again. The rats were observed for 5 min without receiving shock. The administration of PD135158 30 min before conditioned-fear stress significantly reduced freezing behavior. PD135158 blocked the expression of conditioned fear. PD135158 was again administered 30 min before footshock. Then, the rats were individually subjected to 30 min of inescapable electric footshock in the shock chamber. Twenty-four hours after receiving footshock, the rats were again placed in the shock chamber and observed for 5 min without shock administration. The administration of PD135158 30 min before footshock significantly reduced conditioned freezing. PD135158 blocked the anxiety of conditioned fear. PD135158 blocked not only the anxiety, but also the expression of conditioned fear. These results suggest that CCKB receptor might play an important role in conditioned-fear stress. They indicate that CCKB receptor is related to anxiety.
本研究的目的是确定CCKB受体拮抗剂PD135158是否能抑制条件性恐惧。将大鼠单独置于带有格栅地板的实验箱中，接受30分钟不可逃避的足部电击。在再次将大鼠放入电击箱前30分钟，给予PD135158或溶剂。观察大鼠5分钟，期间不给予电击。在条件性恐惧应激前30分钟给予PD135158可显著降低僵住行为。PD135158可阻断条件性恐惧的表达。在足部电击前30分钟再次给予PD135158。然后，将大鼠单独置于电击箱中，接受30分钟不可逃避的足部电击。接受足部电击24小时后，再次将大鼠放入电击箱，观察5分钟，期间不给予电击。在足部电击前30分钟给予PD135158可显著降低条件性僵住。PD135158可阻断条件性恐惧的焦虑。PD135158不仅可阻断焦虑，还可阻断条件性恐惧的表达。这些结果表明，CCKB受体可能在条件性恐惧应激中起重要作用。它们表明CCKB受体与焦虑有关。
