Expression of progesterone receptor isoforms in corpora lutea of human subjects: correlation with serum oestrogen and progesterone concentrations.
To understand the biological significance of progesterone receptor forms A (PR-A) and B (PR-B) in human corpus luteum, the expression of mRNA and serum steroid hormone concentrations were determined simultaneously in the luteal stages. The expression of PR-A mRNA predominated over PR-B mRNA in all samples analysed. Total PR (PR-AB) and PR-B mRNA concentrations at the late secretory phase were significantly (P < 0.01) lower than those at the early and mid secretory phases of the menstrual cycle. The ratio of PR-B to PR-AB mRNA concentration showed no significant change during the secretory phase. In the early and mid secretory phases, there was a negative correlation between PR-B mRNA concentration and serum progesterone concentration, and between the ratio of PR-B to PR-AB mRNA concentrations and serum progesterone concentration (P < 0.01). These findings suggest that human corpus luteum might intracellularly synthesize PR-A and PR-B, and thus be involved in the steroid functional regulation of the corpus luteum, especially at the early and mid secretory phases, and that progesterone might regulate the synthesis of PR-A and PR-B.
Misao
R
R
Department of Obstetrics and Gynecology, Gifu University School of Medicine, Japan.
Nakanishi
Y
Y
Iwagaki
S
S
Fujimoto
J
J
Tamaya
T
T
D000328:Adult; D003338:Corpus Luteum / Q000502:physiology*; D004967:Estrogens / Q000097:blood*; D005260:Female; D006801:Humans; D008875:Middle Aged; D011374:Progesterone / Q000097:blood*; D020033:Protein Isoforms / Q000096:biosynthesis; D012333:RNA, Messenger / Q000096:biosynthesis; D011980:Receptors, Progesterone / Q000096:biosynthesis*
D004967:Estrogens; D020033:Protein Isoforms; D012333:RNA, Messenger; D011980:Receptors, Progesterone; D011374:Progesterone