Ultrastructural and endocrinological study of the human endometrium and decidua using the organ culture method

Explants of human endometrium and decidua were cultured for 96 hours using the organ culture method. The tissues were observed under light and electron microscopes. The prolactin concentrations of the mediums and of the tissues were assayed with I131-prolactin kits. The prolactin concentrations in the mediums continued to increase during the 96-hour organ culture to 16ng/100mg w.w. for the proliferative endometrium, 200ng/100mg w.w. for the late secretory endometrium and 5.5 micrograms/100mg w.w. for the early gestational decidua. Ultrastructurally, each endometrial stromal cell and decidual stromal cell revealed its secretory appearance. For instance, after the culture there was an increase in ribosomes and Golgi apparatus, and the cisternae of the rough endoplasmic reticulum (r-ER) expanded. The differentiation of the stromal cells into fully developed decidual cells in ultrastructure was proportional to the increase in prolactin concentrations in the medium during the culture.