Neuronal connection between the posterior insular cortex and the amygdara in rats : an elelctrophysiological study

在这个项目中，我们研究了后岛叶皮质中的神经元连接。我们用钨电极记录了电刺激杏仁核或丘脑网状核后岛叶皮质的细胞外神经反应。16个神经元被鉴定为对杏仁核的电刺激有反应。杏仁核16个刺激点中，9个位于基底外侧核，4个位于基底内侧核，2个位于中央核，1个位于外侧核。电刺激杏仁核诱发岛叶后皮质神经元突触和/或动作电位，潜伏期平均15.3ms(n=16，2.9~88.5)。本研究中记录的大多数神经元也对电刺激喉上神经(SLN)有反应。观察到杏仁核和SLN传入之间的相互作用。电刺激丘脑网状核等不同部位后，43例后岛叶皮质出现动作电位和/或复合动作电位反应。在43个刺激点中，16个位于内囊，13个位于丘脑网状核，4个位于杏仁复合体，4个位于尾壳核，3个位于同侧岛叶皮质后最后部，2个位于丘脑内侧背侧核，1个位于丘脑腹后外侧核。潜伏期0.8~42.3ms，平均5.8ms(n=43)。在本研究中，15例观察到连接类型，7例表现为逆行反应，主要来自内囊(6/7)，8例表现为顺行反应，主要来自丘脑网状核(5/8)。这些数据表明，岛叶皮质与丘脑网状核(和杏仁核)之间的联系可能在岛叶后皮质的信息处理中起重要作用。

In this project we examined the neuronal connections in the posterior insular cortex. We recorded the extracellular neural responses from the posterior insular cortex following electrical stimulation of the amygdala or the thalamic reticular nucleus, using a tungsten electrode. Sixteen neurons were identified to respond to electrical stimulation of the amygdala. Of the 16 stimulation sites in the amygdala, 9 were found in the basolateral nucleus, 4 in the basomedial nucleus, 2 in the central nucleus, and 1 in the lateral nucleus. Electrical stimulation of the amygdala evoked synaptic potentials and/or action potentials in the posterior insular cortex neurons with a mean latency of 15.3 ms (n = 16, range, 2.9-88.5). Most of the neurons recorded in the present study were also responsive to electrical stimulation of the superior laryngeal nerve (SLN). Interactions between amygdala and SLN inputs were observed. Following electrical stimulation of the various brain sites including the thalamic reticular nucleus, 43 cases in the posterior insular cortex responded with action potential and/or compound action potential. Of the 43 stimulation sites, 16 were found in the internal capsule, 13 in the thalamic reticular nucleus, 4 in the amygdaloid complex, 4 in the caudate putamen, 3 in the ipsilateral posterior-most portion of the insular cortex, 2 in the mediodorsal thalamic nucleus, and 1 in the ventral posterolateral thalamic nucleus. The average latency was 5.8 ms (n = 43), ranging from 0.8 to 42.3 ms. In the present study, 15 cases were examined the types of connection ; 7 showed an antidromic response, mainly from the internal capsule (6/7) and 8 showed an orthodromic response, mainly from the thalamic reticular nucleus (5/8). These data suggest that connection between insular cortex and the thalamic reticular nucleus (and the amygdara) may have an important role in information processing in the posterior insular cortex.