Coote J H, Lewis D I
Department of Physiology, University of Birmingham, Edgbaston, UK.
Clin Exp Hypertens. 1995 Jan-Feb;17(1-2):295-311. doi: 10.3109/10641969509087072.
Baroreceptor inhibition of a spinally evoked response in a renal nerve was studied following removal of excitatory drive from the rostral ventrolateral medulla (RVLM), by microinjecting glycine into this region (RVLM block). Activation of arterial baroreceptors was still able to inhibit a spinally evoked response after RVLM block and this effect was abolished by intrathecal strychnine. Intrathecal bicuculline also was shown to reduce the magnitude of the baroreceptor inhibition but only when the RVLM was intact indicating that bicuculline was removing a facilitation. Both strychnine and bicuculline antagonised an NTS induced inhibition of activity in single sympathetic preganglionic neurones. It is concluded that arterial baroreceptor reflex regulation of vasomotor activity occurs at a spinal as well as a supraspinal site and GABA and glycine are the likely inhibitory mediators at both sites.
通过向延髓头端腹外侧区（RVLM）微量注射甘氨酸以消除其兴奋性驱动（RVLM阻断）后，研究了压力感受器对肾神经中脊髓诱发反应的抑制作用。在RVLM阻断后，动脉压力感受器的激活仍能抑制脊髓诱发反应，且鞘内注射士的宁可消除此效应。鞘内注射荷包牡丹碱也显示可降低压力感受器抑制的幅度，但仅在RVLM完整时出现，这表明荷包牡丹碱消除了一种易化作用。士的宁和荷包牡丹碱均拮抗了孤束核（NTS）诱导的单交感神经节前神经元活动抑制。结论是，动脉压力感受器对血管运动活动的反射调节发生在脊髓以及脊髓以上部位，且GABA和甘氨酸可能是这两个部位的抑制性介质。
