Zhong S, Barman S M, Gebber G L
Department of Pharmacology, Michigan State University, East Lansing 48824-1317.
Am J Physiol. 1992 Jun;262(6 Pt 2):R1015-24. doi: 10.1152/ajpregu.1992.262.6.R1015.
We studied the effects of brain stem lesions or transection on the 10-Hz and 2- to 6-Hz rhythms in sympathetic nerve discharge (SND) in baroreceptor-denervated unanesthetized decerebrate cats. The results indicate that these two rhythms depend in part on different brain stem regions. The 10-Hz rhythm was eliminated by ablation of the rostral ventrolateral medulla (RVLM), medullary raphe complex, or pontine parabrachial and Kölliker-Fuse complex (PB/KF) or by pontomedullary border transection. Except for RVLM lesions, these procedures did not disrupt the 2- to 6-Hz rhythm in SND. In fact the power in SND at frequencies less than 6 Hz was increased by raphe or PB/KF lesions. Total power in SND was not significantly affected by raphe or PB/KF lesions, but mean arterial pressure was significantly reduced. Field potentials recorded from the RVLM (11 of 26 sites) and raphe (10 of 20 sites) were correlated to the 10-Hz rhythm in SND, further supporting a role of these areas in either generating or relaying this rhythm to sympathetic nerves. In contrast, field potentials recorded from the PB/KF were not correlated to the 10-Hz rhythm in SND. Thus this region may provide a tonic drive to the 10-Hz generator located elsewhere in the brain stem.
我们研究了脑干损伤或横断对压力感受器去神经支配的未麻醉去大脑猫交感神经放电（SND）中10赫兹以及2至6赫兹节律的影响。结果表明，这两种节律部分依赖于不同的脑干区域。通过切除延髓头端腹外侧区（RVLM）、延髓中缝复合体、脑桥臂旁核和 Kölliker-Fuse 复合体（PB/KF）或通过脑桥延髓交界处横断可消除10赫兹节律。除RVLM损伤外，这些操作并未破坏SND中的2至6赫兹节律。事实上，中缝核或PB/KF损伤会增加SND中频率低于6赫兹的功率。中缝核或PB/KF损伤对SND的总功率没有显著影响，但平均动脉压显著降低。从RVLM（26个位点中的11个）和中缝核（20个位点中的10个）记录的场电位与SND中的10赫兹节律相关，进一步支持了这些区域在产生该节律或将其传递至交感神经方面的作用。相比之下，从PB/KF记录的场电位与SND中的10赫兹节律不相关。因此，该区域可能为位于脑干其他部位的10赫兹节律发生器提供紧张性驱动。
