Histochemistry and ultrastructure of adrenal cortical development in the golden hamster

Abstract

Adrenal glands were collected from fetuses of golden hamsters at 12 1 2 , 14 1 2 , and 15 1 2 days' gestation and from newborn animals. Samples were prepared for light microscopy, histochemical analyses, and electron microscopy. Ultrastructural differentiation of the fetal adrenal was characterized by the development of zonation and typical steroid-producing cells. At 12 1 2 days' gestation, cortical cells had smooth borders, many polyribosomes, and contained mitochrondria with lamellar cristae. Smooth endoplasmic reticulum was not evident. Signs of functional zonation into deep and superficial zones were evident by 14 1 2 days' gestation. Cortical cells of the superficial zone contained scattered lipid droplets, small Golgi areas, and mitochrondria with lamellar cristae. This zone later developed into the adult zona glomerulosa. The cortical cells of the deep zone were characterized by mitochondria containing tubulovesicular cristate, well-developed Golgi areas, vesicular smooth endoplasmic reticulum, and lysosomes. At 15 1 2 days' gestation and in newborn animals the zonation was more prominent, and desmosomes and tight junctions were present between the deep cortical cells. High levels of acid phosphatase, alkaline phosphatase, and esterase were present in the deep cortex, but lower activity occurred in the superficial zone. The activity of 3β-hydroxysteroid dehydrogenase was low in all specimens.