VI. The chromaffine system of annelids and the relation of this system to the contractile vascular system in the leech, hirudo medicinalis. - A contribution to the comparative physiology of the contractile vascular system and its regulators, the adrenalin secreting system and the sympathetic nervous system

Abstract

The Distribution of the Chromaffine System in the Annelid Kingdom. The possession of a chromaffine system, consisting of cells which take a yellow stain with chrome salts, is a common property of almost all the members of the vertebrate kingdom. The presence of this reaction is coincident with, and probably dependent upon, the secretion by these cells of the substance adrenalin. The investigations of Lewandowski (30), Langley (29), Elliott (11), and others have established that the physiological actions of this latter substance are the same as those which result from the stimulation of the sympathetic nervous system. The latest researches of Elliott (12), Von Anrep (43) and others, have shown in addition that the adjuvant action of adrenalin is essential for the efficient performance of the functions of the sympathetic nervous system. This is supported by pathological considerations, for it has long been recognised that many of the symptoms of Addison’s disease, in which the chief lesion is the destruction of the medullary chromaffine tissue of the suprarenal glands, are those of failure of the sympathetic nervous system. From a physiological standpoint, it is, therefore, necessary that the two systems should co-exist, and a close morphological relationship between them is rendered probable. The researches of Kohn (26) on the embryological origin of the chromaffine system in the mammalia have established that the ganglion cells of the sympathetic system and the cells of the chromaffine system, which are in the embryo widely distributed through the body, arise from a common group of mother cells; Kohn therefore names the chromaffine system the Paraganglion system. These researches are in agreement with the original statement of Balfour (2) that the paired suprarenal bodies of Elasmobranchs, which consist of chromaffine cells, are developed in the sympathetic ganglion masses; Kohn has also made similar investigations in these fishes and confirmed the observations of Balfour.