Role of vagal afferents and the rostral ventral medulla in intravenous serotonin-induced changes in nociception and arterial blood pressure.
Role of vagal afferents and the rostral ventral medulla in intravenous serotonin-induced changes in nociception and arterial blood pressure.
复制标题
迷走神经传入和延髓头端腹侧在静脉血清素引起的伤害感受和动脉血压变化中的作用。
DOI：
10.1016/s0031-9384(99)00128-6
复制
发表时间：
1999
影响因子：
2.9
通讯作者：
Barnes-Noble,D
中科院分区：
文献类型：
--
作者：
Thurston-Stanfield,CL;Ranieri,JT;Vallabhapurapu,R;Barnes-Noble,D
瑟斯顿-斯坦菲尔德角L.，J. T.拉涅里河VALLABHAPURAPU和D.巴恩斯-诺布尔。迷走神经传入和延髓头端腹侧区在静脉注射曲马多宁引起的伤害感受和动脉血压变化中的作用。《物理学》第五卷第67卷第5期第753-767页，1999年。静脉注射5-羟色胺可部分通过激活迷走神经传入抑制伤害性甩尾反射。本研究探讨了延髓头端腹侧区（RVM）在静脉注射曲马多宁产生的TF反射抑制中的作用。在实验1中，测定了RVM的麻醉阻断对马槟榔素产生的TF抑制的影响。利多卡因减弱了阿托伐他汀对TF反射的抑制作用，但对5-羟色胺的心血管效应没有影响。在实验2中，静脉注射5-羟色胺对RVM的神经活动在完整的和心肺去传入大鼠的影响进行了测定。RVM中的神经元被分为ON和OFF细胞，其中ON细胞被有害热激活，OFF细胞被抑制。然后测定静脉注射5-羟色胺对TF潜伏期、血压和ON或OFF细胞活性的影响。在完整的大鼠，5-羟色胺产生剂量依赖性增加TF潜伏期，血压的三相变化，和双相或三相的ON或OFF细胞活性的变化。血压的变化包括最初的血压急剧下降（Bezold-Jorch反射），随后是短暂的升压反应，随后是延迟的降压反应。ON细胞普遍兴奋，虽然有一个时期，在此期间，兴奋下降。OFF细胞最初被兴奋，随后是一段时间的抑制，随后是第二段时间的兴奋。双侧颈迷走神经切断可减弱TF潜伏期的延长、Bezold-Jorch反射和OFF细胞的兴奋，增强ON细胞的兴奋和升压反应。双侧窦主动脉去传入减弱了Bezold-Jorch反射，增强了升压反应。这些发现表明静脉注射5-羟色胺通过至少两种不同的机制抑制TF反射，其中一种机制需要RVM。此外，5-羟色胺产生迷走神经介导的OFF细胞的兴奋和ON细胞的抑制，这可能介导一些抗伤害感受。
THURSTON–STANFIELD, C. L., J. T. RANIERI, R. VALLABHAPURAPU AND D. BARNES–NOBLE. Role of vagal afferents and the rostral ventral medulla in intravenous serotonin-induced changes in nociception and arterial blood pressure. PHYSIOL BEHAV 67(5) 753–767, 1999.—Intravenous administration of serotonin inhibits the nociceptive tail-flick (TF) reflex, partially through activation of vagal afferents. The present study examined the role of the rostral ventral medulla (RVM) in i.v. serotonin-produced inhibition of the TF reflex. In Experiment 1, the effects of anesthetic blockade of the RVM on serotonin-produced inhibition of the TF were determined. Lidocaine attenuated the serotonin-produced inhibition of the TF reflex, but had no effect on the cardiovascular effects of serotonin. In Experiment 2, the effects of i.v. serotonin on neural activity in the RVM in intact and cardiopulmonary deafferented rats were determined. Neurons in the RVM were classified as ON and OFF cells, where ON cells were excited by noxious heat, and OFF cells were inhibited. The effects of i.v. serotonin on TF latency, blood pressure, and ON or OFF cell activity were then determined. In intact rats, serotonin produced a dose-dependent increase in TF latency, triphasic changes in blood pressure, and bi- or triphasic changes in ON or OFF cell activity. The changes in blood pressure included an initial sharp decrease in blood pressure (Bezold–Jarisch reflex), followed by a brief pressor response, followed by a delay depressor response. ON cells were generally excited, although there was a period during which the excitation decreased. OFF cells were initially excited, followed by a period of inhibition, followed by a second period of excitation. Bilateral cervical vagotomy attenuated the increase in TF latency, the Bezold–Jarisch reflex, and the excitation of OFF cells, and potentiated the excitation of ON cells and the pressor response. Bilateral sinoaortic deafferentation attenuated the Bezold–Jarisch reflex and potentiated the pressor response. These findings indicate that i.v. serotonin inhibits the TF reflex through at least two distinct mechansims, one of which requires the RVM. In addition, serotonin produces a vagally mediated excitation of OFF cells and inhibition of ON cells that may mediate some of the antinociception.