Onimaru H, Homma I
Department of Physiology, Showa University School of Medicine, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan.
Neuroscience. 2007 Jan 5;144(1):387-94. doi: 10.1016/j.neuroscience.2006.09.033. Epub 2006 Oct 30.
The amygdala is important for the formation of emotions that are affected by olfactory information. The piriform cortex is involved in information processing related to olfaction. To investigate functional interactions between the piriform cortex and amygdala and their relation to medullary respiratory activity, we developed a novel in vitro preparation including the limbic system, brainstem, and spinal cord of newborn rats. With the use of optical and electrophysiologic recordings, we analyzed spontaneous neuronal activity in the piriform-amygdala complex in limbic-brainstem-spinal cord preparations from 0- to 1-day-old rats. For optical recordings, the preparation was stained with a voltage-sensitive dye, and inspiratory activity was monitored from the fourth cervical (C4) ventral root. Spontaneous oscillatory burst activity (up to 10/min) was detected from the rostral cut surface of limbic and para-limbic regions including the piriform cortex and amygdala. The burst activity initially appeared in the piriform cortex and then propagated to the amygdala. We averaged the imaging data in the limbic area with the use of C4 inspiratory activity as a trigger signal. The results suggest functional coupling of the rhythmic burst activity in the piriform-amygdala complex to medullary inspiratory activity, which was confirmed electrophysiologically by cross-correlation analysis of these signals. This rhythmic burst activity may be involved in the development of neuronal circuits that process information related to olfaction, emotion, and respiration.
杏仁核对于受嗅觉信息影响的情绪形成很重要。梨状皮层参与与嗅觉相关的信息处理。为了研究梨状皮层与杏仁核之间的功能相互作用及其与延髓呼吸活动的关系，我们开发了一种新型的体外制备方法，包括新生大鼠的边缘系统、脑干和脊髓。通过光学和电生理记录，我们分析了0至1日龄大鼠边缘 - 脑干 - 脊髓制备物中梨状 - 杏仁核复合体的自发神经元活动。对于光学记录，制备物用电压敏感染料染色，并从第四颈（C4）腹根监测吸气活动。从包括梨状皮层和杏仁核在内的边缘和旁边缘区域的 Rostral 切面检测到自发振荡爆发活动（高达10次/分钟）。爆发活动最初出现在梨状皮层，然后传播到杏仁核。我们以C4吸气活动作为触发信号，对边缘区域的成像数据进行平均。结果表明梨状 - 杏仁核复合体中的节律性爆发活动与延髓吸气活动存在功能耦合，这通过对这些信号的互相关分析在电生理学上得到了证实。这种节律性爆发活动可能参与了处理与嗅觉、情绪和呼吸相关信息的神经回路的发育。
