CYCLIC CHANGES IN INTERSTITIAL GLAND TISSUE OF THE HUMAN OVARY.

Abstract

AbstractThree distinct types of gland cells occur in adult human ovaries and those of other mammals. These are: (1) Interstitial gland cells formed from the theca interna cells of degenerating (atretic) follicles, hence present from infancy to old age; (2) Thecal gland cells formed from the theca interna cells of ripening follicles, hence present only in individuals that are sexually mature or nearly so, and in these only at or near the time of ovulation; (3) Luteal cells formed from the granulosa cells of ovulated follicles and from the undifferentiated stroma cells surrounding these, and in certain species also from the same sources in relation to atretic follicles. These latter are the so‐called accessory corpora lutea. Primary and accessory corpora lutea are present normally only after ovulation occurs and appear to function for a relatively short time unless pregnancy ensues. In certain species other types of gland cells occur in the ovary and mesovarium; these include the paraluteal cells of the human ovary. Paraluteal cells are not persistent thecal gland cells, but are differentiated from surrounding stroma after the thecal gland disappears. They are probably intermediate stages in the differentiation of luteal cells from stroma cells. Planimetric measurements and computations made from serial sections of human ovaries indicate that in non‐pregnancy and early pregnancy the volume of interstitial gland tissue is less than 1% of the total ovarian volume. However, in the last trimester of gestation, the relative amount of interstitial gland tissue increases rapidly to roughly from 4% to 6% of the total ovarian volume. The largest amount in our series was 5.6%. Luteal gland tissue at the height of its development in the first trimester of gestation reached 31% of the total ovarian volume. In human ovaries the cells of the interstitial gland tissue of late pregnancy seem to be consistently larger and to have a more finely granular cytoplasm than those of early pregnancy or nonpregnancy. The literature shows that mammalian interstitial gland cells of comparable origin to the human cells discussed in this paper have the following characteristics which are known to be indicative of steroid secretors: Numerous birefringent, acetone soluble, autofluorescent granules which react with sulphuric acid and are Schultz and Schiff positive; mitochondria with anastomosing tubular cristae; and smooth tubular endoplasmic reticulum. Physiological studies so far reported have indicated possible estrogen, androgen, and progesterone production by interstitial gland cells, but all of the evidence is too scanty, indirect, and at times contradictory to be convincing. Since interstitial gland cells are present from birth to old age, and show cycles of abundance and differentiation correlated with the reproductive age and cycles, they may prove to be the most important ovarian gland cells when their function is fully understood.