Abstract：
Respiration is regulated by various types of neurons located in the pontine-medullary regions. The Kölliker-Fuse (KF)/A7 noradrenergic neurons play a role in modulating the inspiratory cycle by influencing the respiratory output. These neurons are interconnected and may also project to brainstem and spinal cord, potentially involved in regulating the post-inspiratory phase. In the present study, we hypothesize that the parafacial (pF) neurons, in conjunction with adrenergic mechanisms originating from the KF/A7 region, may provide the neurophysiological basis for breathing modulation. We conducted experiments using urethane-anesthetized, vagotomized, and artificially ventilated male Wistar rats. Injection of L-glutamate into the KF/A7 region resulted in inhibition of inspiratory activity, and a prolonged and high-amplitude genioglossal activity (GGEMG). Blockade of the α1 adrenergic receptors (α1-AR) or the ionotropic glutamatergic receptors in the pF region decrease the activity of the GGEMG without affecting inspiratory cessation. In contrast, blockade of α2-AR in the pF region extended the duration of GG activity. Notably, the inspiratory and GGEMG activities induced by KF/A7 stimulation were completely blocked by bilateral blockade of glutamatergic receptors in the Bötzinger complex (BötC). While our study found a limited role for α1 and α2 adrenergic receptors at the pF level in modulating the breathing response to KF/A7 stimulation, it became evident that BötC neurons are responsible for the respiratory effects induced by KF/A7 stimulation.
摘要：
呼吸由位于脑桥-髓质区域中的各种类型的神经元调节。Kölliker-Fuse（KF）/A7去甲肾上腺素能神经元通过影响呼吸输出在调节吸气周期中起作用。这些神经元相互联系，也可能投射到脑干和脊髓，可能参与调节吸气后阶段。在本研究中,我们假设面旁(pF)神经元，与源自KF/A7区域的肾上腺素能机制相结合，可以为呼吸调节提供神经生理学基础。我们使用尿烷麻醉进行了实验，迷走神经切断术，人工通风的雄性Wistar大鼠.向KF/A7区域注射L-谷氨酸导致吸气活性的抑制,和长时间的高振幅生殖舌体活动（GGEMG）。pF区域中α1肾上腺素能受体（α1-AR）或离子型谷氨酸能受体的阻断会降低GGEMG的活性，而不会影响吸气停止。相比之下,pF区域中α2-AR的阻断延长了GG活性的持续时间。值得注意的是,KF/A7刺激诱导的吸气和GGEMG活动被Bötzinger复合物（BötC）中谷氨酸能受体的双侧阻断完全阻断。虽然我们的研究发现pF水平的α1和α2肾上腺素能受体在调节对KF/A7刺激的呼吸反应中的作用有限，很明显BötC神经元负责KF/A7刺激诱导的呼吸效应。
