Wang Jinghua, Wang Min, Wei Zhifeng, Li Mingxian, Huang Min, Wang Shao
Pediatric Cardiology, First Hospital of Jilin University, Changchun, Jilin, China.
Sleep Breath. 2014 Sep;18(3):491-7. doi: 10.1007/s11325-013-0910-8. Epub 2013 Nov 20.
The insular cortex (Ic) and habenular nuclei (Hb) of the limbic system are associated with human and animal dyspnea by regulating 5-hydroxytryptamine (5-HT) release in the raphe nuclei (RN). However, the Hb are composed of the medial habenular nucleus (MHb) and the lateral habenular nucleus (LHb). Therefore, it is still unclear whether the Ic signal is conducted through the MHb or LHb. This study aimed to investigate the role of the Hb and Ic in obstructive sleep apnea syndrome (OSA) and the functional relationship between these two structures.
We monitored multiple indicators, including the respiration movement curve, neuronal activity in the MHb and LHb, and arterial blood gas, when stimulating the anterior Ic of Wistar rats. We compared the results with the control group (stimulating the surrounding cortex).
Electrical stimulation of the Ic in the rat brain caused respiratory disturbances, apnea, reduced blood pH, and aggravated base deficit (more negative base excess value) compared to control animals (p < 0.05). It also reduced the spontaneous firing of the MHb neurons but increased that of the LHb neurons. Electrical stimulation of the Ic induces apnea in rats in a similar manner to human OSA. The Ic and the Hb are functionally linked. Stimulation of the Ic inhibits the MHb, but activates the LHb. It induces OSA-like symptoms by enhancing LHb-mediated inhibition of the RN.
This study illustrates the mechanism by which an animal model of OSA is created by stimulating the Ic and promotes understanding of OSA pathogenesis.
边缘系统的岛叶皮质（Ic）和缰核（Hb）通过调节中缝核（RN）中5-羟色胺（5-HT）的释放，与人及动物的呼吸困难相关。然而，Hb由内侧缰核（MHb）和外侧缰核（LHb）组成。因此，Ic信号是通过MHb还是LHb传导仍不清楚。本研究旨在探讨Hb和Ic在阻塞性睡眠呼吸暂停综合征（OSA）中的作用以及这两个结构之间的功能关系。
在刺激Wistar大鼠的前Ic时，我们监测了多个指标，包括呼吸运动曲线、MHb和LHb中的神经元活动以及动脉血气。我们将结果与对照组（刺激周围皮质）进行比较。
与对照动物相比，对大鼠脑内Ic进行电刺激会导致呼吸紊乱、呼吸暂停、血液pH值降低以及碱缺失加重（碱过剩值更负）（p < 0.05）。它还会减少MHb神经元的自发放电，但增加LHb神经元的自发放电。对Ic进行电刺激以类似于人类OSA的方式诱导大鼠呼吸暂停。Ic和Hb在功能上相互关联。刺激Ic会抑制MHb，但激活LHb。它通过增强LHb介导的对RN的抑制作用诱导OSA样症状。
本研究阐明了通过刺激Ic建立OSA动物模型的机制，并促进了对OSA发病机制的理解。
