Arterial baroreceptor and vagal inputs to sympathoexcitatory neurons in rat medulla.
Arterial baroreceptor and vagal inputs to sympathoexcitatory neurons in rat medulla.
复制标题
动脉压力感受器和迷走神经对大鼠髓质交感兴奋神经元的输入。
DOI：
10.1152/ajpregu.1987.252.4.r699
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发表时间：
1987
期刊：
影响因子：
--
通讯作者：
Guyenet,PG
中科院分区：
文献类型：
--
作者：
Sun,MK;Guyenet,PG
记录大鼠腰交感神经放电和位于巨细胞旁外侧核（PGCL）的网状脊髓交感兴奋（SE）神经元的单位活动。双侧微量注射20 pmol甲碘荷包牡丹碱（BIC，一种GABA受体拮抗剂）到PGCL，消除了由低频刺激迷走神经传入产生的交感神经抑制，并通过注射100 pmol转换为升压反应。这些BIC注射也以剂量依赖性方式抑制动脉压力感受性反射。与此相反，选择性阻断由高频刺激迷走神经传入神经产生的交感兴奋双侧注射犬尿烯酸（KYN，谷氨酸受体拮抗剂）到PGCL。在所有记录的SE神经元中检测到迷走神经兴奋性、迷走神经抑制性和动脉压力感受器输入的会聚。迷走神经传入的单脉冲刺激产生了两个峰值的SE神经元的兴奋，都被KYN的离子电渗应用程序和至少一个抑制期选择性地阻断BIC的离子电渗。结果强调了SE神经元及其周围区域在整合脑血管输出到脊髓节前神经元中的重要性。
Lumbar sympathetic nerve discharge and unit activity of reticulospinal sympathoexcitatory (SE) neurons located in nucleus paragigantocellularis lateralis (PGCL) were recorded in rats. The sympathoinhibition produced by low-frequency stimulation of vagal afferents was abolished by bilateral microinjections of 20 pmol of bicuculline methiodide (BIC, a GABA-receptor antagonist) into PGCL and was converted into a pressor response by injections of 100 pmol. These BIC injections also inhibited the arterial baroreflex in a dose-dependent manner. In contrast the sympathoexcitation produced by high-frequency stimulation of vagal afferents was selectively blocked by bilateral injections of kynurenic acid (KYN, a Glu-receptor antagonist) into PGCL. Convergence of vagal excitatory, vagal inhibitory, and arterial baroreceptor inputs was detected in all SE neurons recorded. Single-pulse stimulation of vagal afferents produced up to two peaks of excitation of SE neurons, both blocked by iontophoretic applications of KYN and at least one inhibitory period selectively blocked by iontophoresis of BIC. The results emphasize the importance of SE neurons and surrounding area in integrating the brain vasomotor output to spinal preganglionic neurons.