Effect of progesterone on protein synthesis and secretion by cultured epithelial cells from guinea-pig endometrium

The pattern of proteins synthesized and secreted in response to progesterone by guinea-pig endometrial epithelial cell cultured with estradiol-17 beta was investigated. Glandular epithelial cells were maintained in culture for 3 days on growth medium, then washed three times with a steroid-free medium. After this period, 2 x 10(-8) M estradiol-17 beta or 2 x 10(-8) M estradiol-17 beta plus 5 x 10(-7) M progesterone were added to the medium for 48 h. To study biochemical changes, the proteins in medium and in cells were analyzed by one- and two-dimensional polyacrylamide gel electrophoresis, followed by fluorography. The addition of progesterone to estradiol-17 beta in the culture medium caused a change in the patterns of cellular and secreted proteins: one-dimensional gel electrophoresis showed that variation of 8 cellular proteins and 12 secreted proteins was caused by progesterone. Induction of individual proteins by progesterone treatment was observed by two-dimensional gel electrophoresis: one cellular protein (Mr 49,000; pI 5.90) and one secreted protein (Mr 14,300; pI 4.80) were specifically induced and might serve as markers of progesterone action.