Pivotal role of the ventral tegmental area in spontaneous motor activity and concomitant cardiovascular responses in decerebrate rats
Pivotal role of the ventral tegmental area in spontaneous motor activity and concomitant cardiovascular responses in decerebrate rats
复制标题
腹侧被盖区在去大脑大鼠自发运动活动和伴随心血管反应中的关键作用
DOI：
10.1016/j.brainres.2019.146616
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发表时间：
2020
期刊：
影响因子：
2.9
通讯作者：
Matsukawa K.
中科院分区：
文献类型：
--
作者：
Ishii K;Asahara R;Komine H;Liang N;Matsukawa K.
中央指令是来自大脑高级中枢的前馈信号，调节与运动相关的心血管系统。先前的证据表明，中脑周围的核（或多个核）可能有助于产生自发运动活动和伴随的心血管反应。为了检查中脑内的哪个区域对于自发和同步反应是重要的，18只大鼠在三个水平（前中脑、嘴腹侧中脑和尾侧中脑水平）去脑并用神经肌肉阻滞剂麻痹。个体脑切片显示，在前中脑制备中，在前丘水平的吻侧去脑，此外，在吻腹侧中脑制备中，去除了导水管周围灰质，在尾侧中脑制备中，在中丘水平周围去脑。在前中脑准备中，自发运动活动以69 ± 27次/h的频率发生，并伴随心率（15 ± 4次/min）和平均动脉血压（54 ± 4 mmHg）的增加。类似的运动和心血管反应发生在rostroventral中脑准备，而这种反应几乎没有发生在尾侧中脑准备。我们接下来检查了在腹侧被盖区（VTA）注射GABA能受体激动剂（蝇蕈醇）是否抑制6种前中脑制备物中的自发运动和心血管反应。蝇蕈醇对自发活动和伴随的心血管反应的发生有明显的抑制作用（P< 0.05），而对生理盐水无抑制作用。结论：腹侧被盖区在去大脑大鼠运动和心血管系统的自发和同步激活中起着关键作用。
Central command, a feedforward signal from higher brain centers, regulates the cardiovascular system in association with exercise. Previous evidence suggests that nucleus (or nuclei) around the midbrain may contribute to generating spontaneous motor activity and concomitant cardiovascular responses. To examine which area within the midbrain is important for the spontaneous and synchronized responses, 18 rats were decerebrated at three levels (pre-midbrain, rostroventral midbrain, and caudal midbrain levels) and paralyzed with a neuromuscular blocker. Individual brain sections showed decerebration rostral to the pre-collicular level in the pre-midbrain preparation and, additionally, removal of the periaqueductal gray in the rostroventral midbrain preparation, and decerebration around the midcollicular level in the caudal midbrain preparation. Spontaneous motor activity occurred at frequency of 69 ± 27 times/h and accompanied increases in heart rate (by 15 ± 4 beats/min) and mean arterial blood pressure (by 54 ± 4 mmHg) in the pre-midbrain preparation. Similar motor and cardiovascular responses took place in the rostroventral midbrain preparation, while such responses hardly occurred in the caudal midbrain preparation. We next examined whether injection of a GABAergic receptor agonist (muscimol) in the ventral tegmental area (VTA) inhibits the spontaneous motor and cardiovascular responses in 6 pre-midbrain preparations. The occurrence of spontaneous motor activity and concomitant cardiovascular responses was inhibited clearly (P< 0.05) by injection of muscimol, but not saline. It is concluded that the VTA plays a pivotal role in the spontaneous and synchronized activation of the motor and cardiovascular systems in decerebrate rats.