Nichols A J, Wilson A C, Hiley C R
Eur J Pharmacol. 1985 Feb 26;109(2):263-8. doi: 10.1016/0014-2999(85)90428-5.
Cardiac output and its regional distribution were determined with radioactive microspheres in pentobarbitone anaesthetised rats 16 h and 5 days after sympathectomy with 6-hydroxydopamine (150 mg/kg i.p. over 24 h). Distribution was not different at either time in sympathectomised animals compared to controls given i.p. saline/ascorbic acid. Cardiac output was 12% greater 16 h after sympathectomy than in the controls but heart rate and blood pressure were 20% lower. Stroke volume was 43% greater in animals given 6-hydroxydopamine and total peripheral resistance 29% lower than in sham-sympathectomised rats. Five days after sympathectomy, blood pressure and heart rate were still lower in sympathectomised rats, but cardiac output and total peripheral resistance were not significantly different from control. It is concluded that basal sympathetic tone does not determine the distribution of cardiac output at rest and that its primary effect on the heart is to maintain heart rate rather than contractility.
在用6-羟基多巴胺（24小时内腹腔注射150mg/kg）进行交感神经切除术后16小时和5天，使用放射性微球测定戊巴比妥麻醉大鼠的心输出量及其区域分布。与腹腔注射生理盐水/抗坏血酸的对照动物相比，交感神经切除动物在这两个时间点的分布均无差异。交感神经切除术后16小时的心输出量比对照组高12%，但心率和血压低20%。给予6-羟基多巴胺的动物的每搏输出量比假交感神经切除大鼠高43%，总外周阻力低29%。交感神经切除术后5天，交感神经切除大鼠的血压和心率仍然较低，但心输出量和总外周阻力与对照组无显著差异。结论是，基础交感神经张力并不决定静息时的心输出量分布，其对心脏的主要作用是维持心率而非收缩力。
