Wallis D, Watson A H, Mo N
School of Molecular and Medical Biosciences, University of Wales College of Cardiff, Wales.
Microsc Res Tech. 1996 Sep 1;35(1):69-79. doi: 10.1002/(SICI)1097-0029(19960901)35:1<69::AID-JEMT6>3.0.CO;2-N.
The properties of the postganglionic sympathetic neurones supplying the heart and arising in the stellate and adjacent paravertebral ganglia of various species are discussed with respect to their location, morphology, synaptic input and membrane characteristics. Results from our laboratory on the morphology of rat stellate neurones projecting to the heart were obtained either by intracellular injection of hexammine cobaltic (III) chloride or by retrograde labelling of cells using cobalt-lysine complex. Intracellular recordings were made from cells using electrodes filled either with potassium chloride plus hexammine cobaltic chloride or potassium acetate. Neurones which projected axons into cardiac nerve branches arising from the stellate ganglion were termed putative cardiac neurones, because of the possibility that some supply pulmonary targets. Putative cardiac neurones had unbranched axons and were ovoid or polygonal in shape, but showed considerable variation in soma size and in the complexity of dendritic trees. The mean two-dimensional surface area was 463 microns2 and the mean number of primary dendrites was seven. Other studies have found that the morphology of rat stellate ganglion neurones is similar to that of superior cervical ganglion cells. However, in strains of rat displaying spontaneous hypertension, dendritic length may be increased. Histochemical studies do not, as yet, seem to have demonstrated a distinctive neurochemical profile for stellate cardiac neurones, but various types of peptide-containing intraganglionic nerve fibres have been identified in the guinea pig. In our electrophysiological studies, putative cardiac neurones were found to receive a complex presynaptic input arising from the caudal sympathetic trunk and from T1 and T2 thoracic rami. In addition, 16% of cardiac neurones received a synaptic input from the cardiac nerve. The properties of postganglionic parasympathetic neurones distributed in the cardiac plexus and termed intrinsic cardiac neurones are discussed, including the results of studies on cultures of these neurones.
本文讨论了来自不同物种星状神经节及相邻椎旁神经节、支配心脏的节后交感神经元的特性，包括其位置、形态、突触输入和膜特性。我们实验室通过细胞内注射六氨合钴（III）氯化物或使用钴赖氨酸复合物对投射至心脏的大鼠星状神经元进行逆行标记，获得了有关其形态的研究结果。使用填充有氯化钾加六氨合钴氯化物或醋酸钾的电极对细胞进行细胞内记录。由于一些神经元可能支配肺部靶点，因此将轴突投射到源自星状神经节的心脏神经分支中的神经元称为假定心脏神经元。假定心脏神经元的轴突无分支，呈卵形或多边形，但在胞体大小和树突分支复杂性方面存在相当大的差异。平均二维表面积为463平方微米，初级树突的平均数量为7个。其他研究发现，大鼠星状神经节神经元的形态与颈上神经节细胞相似。然而，在表现出自发性高血压的大鼠品系中，树突长度可能会增加。组织化学研究似乎尚未证明星状心脏神经元具有独特的神经化学特征，但在豚鼠中已鉴定出各种含肽的神经节内神经纤维。在我们的电生理研究中，发现假定心脏神经元接受来自尾侧交感干以及T1和T2胸支的复杂突触前输入。此外，16%的心脏神经元接受来自心脏神经的突触输入。本文还讨论了分布在心脏丛中、称为固有心脏神经元的节后副交感神经元的特性，包括对这些神经元培养物的研究结果。
