Oke Yoshihiko, Miwakeichi Fumikazu, Oku Yoshitaka, Hirrlinger Johannes, Hülsmann Swen
Division of Physiome, Department of Physiology, Hyogo College of Medicine, Nishinomiya, Japan.
Department of Statistical Modeling, The Institute of Statistical Mathematics, Tachikawa, Japan.
Front Physiol. 2018 Sep 3;9:1219. doi: 10.3389/fphys.2018.01219. eCollection 2018.
Spontaneous respiratory rhythmic burst activity can be preserved in the preBötzinger Complex (preBötC) of rodent medullary transverse slices. It is known, that the activation sequence of inspiratory neurons in the preBötC stochastically varies from cycle to cycle. To test whether the activation timing of an inspiratory neuron depends on its neurotransmitter, we performed calcium imaging of preBötC neurons using double-transgenic mice expressing EGFP in GlyT2 neurons and tdTomato in GAD65 neurons. Five types of inspiratory neurons were identified using the fluorescence protein expression and the maximum cross-correlation coefficient between neuronal calcium fluctuation and field potential. Regarding the activation sequence, irregular type putative excitatory (GlyT2/GAD65) neurons and irregular type glycinergic (GlyT2/GAD65) neurons tended to be activated early, while regular type putative excitatory neurons, regular type glycinergic neurons tended to be activated later. In conclusion, the different cell types define a general framework for the stochastically changing activation sequence of inspiratory neurons in the preBötC.
啮齿动物延髓横切片的前包钦格复合体（preBötC）中可保留自发呼吸节律性爆发活动。已知，preBötC中吸气神经元的激活顺序在不同周期之间随机变化。为了测试吸气神经元的激活时间是否取决于其神经递质，我们使用在甘氨酸转运体2（GlyT2）神经元中表达增强型绿色荧光蛋白（EGFP）且在谷氨酸脱羧酶65（GAD65）神经元中表达串联番茄红素（tdTomato）的双转基因小鼠，对preBötC神经元进行了钙成像。利用荧光蛋白表达以及神经元钙波动与场电位之间的最大互相关系数，鉴定出了五种类型的吸气神经元。关于激活顺序，不规则型假定兴奋性（GlyT2/GAD65）神经元和不规则型甘氨酸能（GlyT2/GAD65）神经元倾向于较早被激活，而规则型假定兴奋性神经元、规则型甘氨酸能神经元倾向于较晚被激活。总之，不同的细胞类型为preBötC中吸气神经元随机变化的激活顺序定义了一个总体框架。
