[Occurrence and structure of accessory adrenal glands in Wistar rats].

In complete series of histological sections through the entire abdomen of one normal Wistar-rat, one untreated and two bilaterally adrenalectomized, spontaneously hypertensive Wistar-rats accessory suprarenal glands were found in each case. The detailed findings in the various groups of animals investigated were as follows: (1) In the normal animal 10 accessory suprarenal glands were present. They consisted of tiny aggregates of cortical cells and were surrounded by a thin layer of collageneous fibers. The diameters of the accessory suprarenal complexes were in the order of 0.3 mm. (2) In the untreated, spontaneously hypertensive rat three accessory suprarenal glands were found. However, in contrast to what was seen in the normal rat, these complexes were larger and had diameters of up to 1 mm. Some of these accessory suprarenal glands consisted almost exclusively of small, chromophobe cells, whereas in others a rim of such cells was seen to surround a central core of larger and more acidophile cortical cells. There were few and collapsed capillaries. (3) In the bilaterally adrenalectomized, spontaneously hypertensive rats three, respectively four, accessory suprarenal glands were found. They were situated in the retroperitoneum and partly within the adipose capsule of the kidney but never in the place of the exstirpated main suprarenal glands. In one case an accessory gland was found within the fibrous capsule of the kidney and seen to compress the renal parenchyma. In the bilaterally adrenalectomized animals the average diameters of the accessory glands were larger than in the other groups reaching values of up to 5 mm. At least in both animals one of the accessory glands had a diameter comparable to that of the normal suprarenal gland of an untreated animal. The capillaries were dilated and their number was increased in comparison to what was seen in the other groups. In certain regions the cortical tissue of the accessory glands had an appearance resembling that of zona fasciculata and reticularis.