Degeneration of interstitial gland cells of normal and irradiated dog ovary.

The interstitial gland cells of the ovary were studied by electron microscopy in seven Beagle dogs during advanced metestrus. Additionally, the findings of three dogs with an increased activation of the interstitial gland cells after 12 Gy whole-body X-irradiation were also presented. Three groups of interstitial gland cells were distinguished: the immature, the mature and the degenerating cells. The steroid-specific cell organelles of mature interstitial cells were highly developed after irradiation-induced stimulation. At the onset of generation, a circular arrangement of dilated endoplasmic vesicles (demarcation channel) characterized the cells of non-irradiated and of irradiated ovaries. During the early stage of degeneration, different degrees of nuclear shrinkage and of vacuolation of the cytoplasm were seen. A lace-like vacuolation was common in the irradiated ovaries. During the advanced stage of degeneration, the cysts ruptured with resultant shedding of the cytoplasmic organelles into the intercellular space. A new cellular membrane was simultaneously reconstituted and a fibrocyte-like cell appeared. The process is referred as "secretory degeneration" and is presented as a hypothesis.