Blinder K J, Johnson T A, John Massari V
Department of Pharmacology, Howard University College of Medicine, 520 W Street, NW, Washington, DC 20059, USA.
Brain Res. 1998 Sep 7;804(2):325-30. doi: 10.1016/s0006-8993(98)00561-7.
The vagal postganglionic controls of cardiac rate and left ventricular contractility are mediated by separate intracardiac ganglia, the sino-atrial (SA) and cranio-ventricular (CV) ganglia, respectively. We injected a different retrograde tracer into each of these ganglia (in the same animal) and subsequently examined the brain for the presence of single labeled or double labeled vagal preganglionic neurons. Retrogradely labeled cells from either ganglion were found exclusively in the ventrolateral nucleus ambiguus (NA-VL). There was considerable overlap in the distribution of labeled cells from either ganglion, however fewer than 3% of labeled neurons were double labeled. The data are consistent with the hypothesis that the preganglionic controls of cardiac rate and left ventricular contractility are mediated by largely separate but overlapping groups of cardioinhibitory neurons originating from the NA-VL. These neurons have parallel but morphologically independent pathways projecting to the SA and CV ganglia. Physiological experiments are needed to support this hypothesis.
心脏心率和左心室收缩力的迷走神经节后控制分别由心内神经节介导，即窦房（SA）神经节和颅室（CV）神经节。我们在（同一只动物的）每个神经节中注射了不同的逆行示踪剂，随后检查大脑中是否存在单标记或双标记的迷走神经节前神经元。来自任一神经节的逆行标记细胞仅在腹外侧疑核（NA-VL）中发现。来自任一神经节的标记细胞分布有相当大的重叠，然而，双标记的标记神经元不到3%。这些数据与以下假设一致：心率和左心室收缩力的节前控制主要由源自NA-VL的不同但重叠的心脏抑制神经元群介导。这些神经元有平行但形态上独立的投射到SA和CV神经节的通路。需要生理实验来支持这一假设。
