Department of Cellular Biology & Anatomy, Louisiana State University Health Sciences Center, Shreveport, LA, USA.
Department of Cellular Biology & Anatomy, Louisiana State University Health Sciences Center, Shreveport, LA, USA; Department of Biological Sciences, Southern Methodist University, Dallas, TX, USA.
Mol Cell Neurosci. 2021 Jun;113:103615. doi: 10.1016/j.mcn.2021.103615. Epub 2021 Apr 24.
Cardiorespiratory collapse following a seizure is a suspected cause of sudden unexpected death in epilepsy (SUDEP), the leading cause of epilepsy-related mortality. In the commonly used Kcna1 gene knockout (Kcna1) mouse model of SUDEP, cardiorespiratory profiling reveals an array of aberrant breathing patterns that could contribute to risk of seizure-related mortality. However, the brain structures mediating these respiratory abnormalities remain unknown. We hypothesize that Kv1.1 deficiency in respiratory control centers of the brain contribute to respiratory dysfunction in Kcna1 mice leading to increased SUDEP risk. Thus, in this study, we first used immunohistochemistry to map expression of Kv1.1 protein in cardiorespiratory brain regions of wild-type Kcna1 (WT) mice. Next, GFAP and Iba1 immunostaining was used to test for the presence of astrogliosis and microgliosis, respectively, in the cardiorespiratory centers of Kcna1 mice, which could be indicative of seizure-related brain injury that could impair breathing. In WT mice, we detected Kv1.1 protein in all cardiorespiratory centers examined, including the basolateral amygdala, dorsal respiratory group, dorsal motor nucleus of vagus, nucleus ambiguus, ventral respiratory column, and pontine respiratory group, as well as chemosensory centers including the retrotrapezoid and median raphae nuclei. Extensive gliosis was observed in the same areas in Kcna1 mice suggesting that seizure-associated brain injury could contribute to respiratory abnormalities.
癫痫发作后心肺崩溃是癫痫猝死 (SUDEP) 的一个可疑原因,SUDEP 是癫痫相关死亡的主要原因。在常用于 SUDEP 的 Kcna1 基因敲除 (Kcna1) 小鼠模型中,心肺分析揭示了一系列异常呼吸模式,这些模式可能会增加癫痫发作相关死亡率的风险。然而,介导这些呼吸异常的大脑结构仍不清楚。我们假设 Kv1.1 在大脑呼吸控制中心的缺乏导致 Kcna1 小鼠的呼吸功能障碍,从而增加 SUDEP 的风险。因此,在这项研究中,我们首先使用免疫组织化学方法来绘制野生型 Kcna1 (WT) 小鼠心肺脑区 Kv1.1 蛋白的表达图谱。接下来,使用 GFAP 和 Iba1 免疫染色分别检测 Kcna1 小鼠心肺中心的星形胶质细胞增生和小胶质细胞增生,这可能表明与癫痫发作相关的脑损伤会影响呼吸。在 WT 小鼠中,我们在所有检查的心肺中心都检测到 Kv1.1 蛋白,包括基底外侧杏仁核、背侧呼吸组、迷走神经背核、疑核、腹侧呼吸柱和桥脑呼吸组,以及包括延髓梯形核和中缝核在内的化学感觉中心。在 Kcna1 小鼠的相同区域观察到广泛的神经胶质增生,这表明与癫痫发作相关的脑损伤可能导致呼吸异常。