I8l2 



HUMAN ANATOMY. 



excretory ducts, seem to justifv the inclusion of the coccygeal body, at least, pro- 

 visionally, among the organs of internal secretion, as suggested by Walker. 



Irv 



LAB 



RAB 



THE AORTIC BODIES. 



These temporary organs were described by Zuckerkandl ' a few years ago and 

 are also known as th^ bodies of Zuckerkandl. According to their discoverer, as 

 found in the new-born child, they are a pair of small narrow bodies that lie upon the 

 anterior surface of the abdominal aorta, opposite the origin of the inferior mesenteric 

 artery (Fig. 1537), in close relation with the aortic plexus of the sympathetic nerves. 

 Although usually separated, in about 15 percent, of the bodies examined, in which 

 they were invariably present, the bodies were joined by an isthmus into a horseshoe- 

 shaped organ of varying dimensions. 

 Fig. 1537. The right body is usually the larger, 



i^ a with an average vertical length of 1 1.6 



mm. the corresponding dimension of 

 the left body being 8. 8 mm. The ex- 

 tremes of length for the right body 

 are from 8-20 mm., and of the left 

 one from 3-15 mm. The width is 

 about one-fifth of the length, and the 

 thickness something less. The sur- 

 face of the little organ is smooth and 

 its color light brown. Whilst its 

 consistency is about the same as that 

 of the neighboring lymph-nodes, the 

 body is softer than the adjacent sym- 

 pathetic ganglia. The aortic bodies 

 are essentially organs of foetal life or 

 at most of early childhood, and in 

 the adult they are represented by 

 mere atrophic remains (Zucker- 

 kandl). 



The structure of the aortic 

 body includes a fibrous capsule, which 

 is prolonged into the interior as con- 

 nective tissue strands that accompany 

 the numerous blood-vessels entering 

 the organ. The arteries, minute 

 twigs from the aorta, the inferior 

 mesenteric and sometimes the sper- 

 matic, break up into a rich capillary 

 net-work whose wide meshes are 

 filled with closely packed cells of 

 varying size. These are polygonal, 

 spherical or cuboidal in form and distinguished in many cases by exhibiting 

 the peculiar color reaction, after treatment with the chrome-salts, entitling them 

 to be- classed as chromafifine cells. According to the observations of Zucker- 

 kandl, the genetic relations of the sympathetic ganglia, the medulla of the supra- 

 renals, and the aortic bodies are most intimate, since these various structures are 

 derivatives of a continuous primary cell-mass. In consideration of this association 

 and the constant presence of the distinctive chromafifine cells, it is highly probable 

 that the aortic bodies are to be regarded, along with the medullary portion of the 

 suprarenal and the carotid bodies, as appendages or paraganglia of the sympathetic. 



' Verhandlungen der Anatom. Gesellschaft, 1901. 



Aortic bodies of new-born child : RAB. LAB, right 

 and left aortic bodies ; a, aorta ; /»/, inferior mesen- 

 teric artery ; lei, left common iliac ; ic, inferior cava ; 

 li-v, left renal vein ; ap, aortic sympathetic plexus ; 

 w, ureter. X 2. (Zuckerkandl.) 



