THE SUPRARENAL BODY 213 



THE SUPRARENAL BODY 



This body is attached by areolar tissue to the summit of 

 the kidney, and consists of several folia or leaflets. An examina- 

 tion of one of these leaflets will give us an idea of the organ as a 

 whole. The plan of structure seems to be as follows: 



In the connective tissue which supports the folia are found 

 arterial branches derived from the phrenic and renal arteries, 

 besides the suprarenal artery itself. These arteries penetrate the 

 organ, break up immediately into capillaries, which finally con- 

 verge toward the center of the leaflet ; the blood is here col- 

 lected in thin -walled veins, by which it is drained into the supra- 

 renal vein, thus leaving the body. 



The capillary meshes vary in form and size, according to their 

 position. Near the circumference of the leaflets the meshes are 

 small and ovoid; while, as the center is approached, they become 

 elongated. These spaces between the capillaries are filled with 

 compressed, globular, nucleated cells, the smaller containing only 

 perhaps six or eight, while the longer may be occupied by thirty 

 or forty of these cell -elements, which constitute the parenchyma 

 of the organ. This variation in size of the cell -compartments, 

 contributing, as it does, to alter the appearance of the different 

 zones of the tissue, has given rise to a division into cortex and 

 medulla. The cortex is divided from without inward into a zona 

 glomerulosa, zona fasciculata, and zona reticularis. Many nerve- 

 fibers enter the organ with the arteries. They form a plexus, 

 mostly of non-medullated fibers, in the medulla. Ganglion -cells 

 are numerous. The surface is covered with a fibrous capsule con- 

 tinuous with the supporting framework. 



The suprarenal body is also often known as the suprarenal 

 capsule. This body, the spleen, the thyroid and the thymus 

 glands, with certain other organs of less importance, are some- 

 times called "the ductless glands " 



PRACTICAL DEMONSTRATION 



The tissue is best hardened in strong alcohol, and should be cut as soon 

 as the hardening is complete. It will be sufficiently firm to admit of the 

 thinnest sections being made free-hand or with a simple microtome. The 

 sections, stained with hsematoxylin and eosin, give excellent differentiation. 



