在兔延髓尾端腹外侧，增加或减少抑制性血管运动神经元的活动所引发的动脉血压变化，并不涉及皮肤血管床。

Cutaneous vascular bed is not involved in arterial pressure changes elicited by increasing or decreasing the activity of inhibitory vasomotor neurons in caudal ventrolateral medulla in rabbits.

作者信息

Blessing W W, Nalivaiko E

机构信息

Departments of Physiology and Medicine, Centre for Neuroscience, Flinders University, S.A. 5042, Bedford Park, Australia.

出版信息

Neurosci Lett. 2000 Aug 25;290(2):141-4. doi: 10.1016/s0304-3940(00)01336-7.

DOI:10.1016/s0304-3940(00)01336-7

PMID:10936697

Abstract

We determined whether caudal ventrolateral medulla (CVLM) vasodepressor neurons tonically inhibit vasomotor tone in the ear in anesthetized rabbits. Injection of L-glutamate (10 nmol in 100 nl) into the CVLM decreased arterial pressure and increased superior mesenteric conductance. Ear conductance decreased (0.43+/-0.06 to 0. 33+/-0.05 cm s(-1) per mmHg, n=15 injections, 12 rabbits, P<0.01). Conversely, bilateral injection of gamma-aminobutyric acid (100 nmol in 100 nl) increased arterial pressure and decreased superior mesenteric conductance. At the same time ear conductance increased (0.39+/-09 to 0.48+/-0.27 cm s(-1) per mmHg, n=8 injections, eight rabbits, P<0.05). Results suggest that ear vessels are not tonically inhibited by the CVLM vasodepressor neurons. Presympathetic motoneurons regulating cutaneous flow may be excited, rather than inhibited, by the CVLM neurons.

摘要

我们研究了在麻醉兔中，延髓尾端腹外侧区（CVLM）的血管减压神经元是否对耳部血管运动张力具有持续性抑制作用。向CVLM注射L-谷氨酸（100 nl中含10 nmol）可降低动脉血压并增加肠系膜上动脉传导。耳部传导降低（每毫米汞柱从0.43±0.06降至0.33±0.05 cm·s⁻¹，n = 15次注射，12只兔子，P<0.01）。相反，双侧注射γ-氨基丁酸（100 nl中含100 nmol）可升高动脉血压并降低肠系膜上动脉传导。与此同时，耳部传导增加（每毫米汞柱从0.39±0.09升至0.48±0.27 cm·s⁻¹，n = 8次注射，8只兔子，P<0.05）。结果表明，耳部血管不受CVLM血管减压神经元的持续性抑制。调节皮肤血流的交感节前运动神经元可能被CVLM神经元兴奋而非抑制。