Ultrastructure of the human ovary: II. The luteal cell at term

Abstract

The ultrastructure of luteal tissue obtained from term cesarean section deliveries is described. The cytoplasmic organelles of the term luteal cells appeared well preserved and intact. The agranular endoplasmic reticulum (ER) compared favorably with that reported in luteal cells of corpora lutea of the menstrual cycle. Localized concentrations of an atypical granular ER are described and its continuity with the agranular ER was recognized. Mitochondria and Golgi complex are well developed and without notable features. Large homogenous globules are frequently seen in luteal cell cytoplasm; these are assumed to represent the “colloid droplets” described by light microscopy. Lipid globules are rarely seen in term luteal cells and the implications of this are discussed. On the basis of the ultrastructure of the term luteal cells, it is concluded that they are not highly degenerate cells and they could be capable of secretion.