Distribution Of Cardiac Ganglia And Localization Of Neurons Innervating The Heart Of Chicken

The distributive regularity of intrinsic ganglia, histological structure and localization of neurons irmen'ating the heart of chicken were studied with methods of gross and microscopic anatomy, histology and HRP(horseradish peroxidase).The results shew that: 1) Cardiac ganglia of chicken distribute in the superior cardiac plexus, the anterior cardiac plexus, the posterior cardiac plexus, the left coronary artery plexus and the right coronary artery plexus. These ganglia mainly lie under the epicardium and in coronary sulcus. Ganglia lying in atria mainly distribute on the dorsum of atria and around big blood vessels at the base of the heart. Ganglia lying in ventricle mainly distribute in coronary' sulcus and upper edge of lateral surface of the ventricle; 2) Cardiac ganglia are encapsulated by a thin connective capsule. There are less ganglionic cells but more connective tissue and nervous fibers in ganglia. The shapes of the cell body of ganglionic cells are mainly spindle and oval; 3) The localization of neurons innervating the heart is as follows: The sympathetic postganglionic neurons are found in the C12-T2 sympathetic trunk ganglia and accumulate in the C12 and Tl. The sensory neurons of spinal nerve distribute in the C12-T2 spinal ganglia and accumulate in the C12 and Tl. The parasympathetic preganglionic neurons are located in the ambiguous nucleus, dorsal motor nucleus of the vagus nerve and reticular formation between the two above nuclei. In parasympathetic preganglionic neurons, there is a relationship localized partly among the ambiguous nucleus, dorsal motor nucleus of the vagus nerve and reiicular formation. The sensory neurons of the vagus lie in the jugular ganglion and nudose ganglion.