Expression of LGR7 in the primate corpus luteum implicates the corpus luteum as a relaxin target organ.
In women, the corpus luteum is the source of circulating relaxin. No previous studies have addressed whether the corpus luteum is also a relaxin target organ. We determined relaxin receptor LGR7 mRNA expression in human term pregnancy corpora lutea and nonhuman primate corpora lutea obtained during the menstrual cycle. Real-time reverse transcription-PCR demonstrated the expression of LGR7 mRNA in both human and rhesus monkey corpora lutea. Rhesus monkey corpora lutea were obtained from naturally cycling animals following documented luteinizing hormone (LH) surges at early, mid-, mid-late, and late luteal phases. Luteal expression of LGR7 mRNA did not show temporal variation. Since the primate corpus luteum is LH dependent, we assessed LGR7 mRNA expression in corpora lutea from rhesus monkeys treated with a gonadotropin-releasing hormone (GnRH) antagonist, which significantly suppressed pituitary LH levels. GnRH antagonist treatment, which also inhibits both progesterone and relaxin production, resulted in a fivefold increase in luteal LGR7 mRNA expression. These data suggest that luteal LGR7 mRNA expression may be regulated by relaxin and/or LH and that the primate corpus luteum is a target organ for relaxin.
Maseelall
Priya B
PB
Department of Obstetrics, Gynecology and Women's Health, New Jersey Medical School, Newark, New Jersey 07103, USA.
Seungdamrong
Aimee
A
Weiss
Gerson
G
Wojtczuk
Andrea S
AS
Donnelly
Robert
R
Stouffer
Richard L
RL
Goldsmith
Laura T
LT
D000818:Animals; D003338:Corpus Luteum / Q000378:metabolism*; D005260:Female; D005786:Gene Expression Regulation; D007987:Gonadotropin-Releasing Hormone / Q000037:antagonists & inhibitors; D006801:Humans; D008183:Luteal Phase / Q000378:metabolism; D007986:Luteinizing Hormone / Q000378:metabolism; D008253:Macaca mulatta / Q000378:metabolism; D008597:Menstrual Cycle / Q000235:genetics; D011247:Pregnancy; D011374:Progesterone / Q000378:metabolism; D043562:Receptors, G-Protein-Coupled / Q000235:genetics*; D018000:Receptors, Peptide / Q000235:genetics*; D012065:Relaxin / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction
C417543:RXFP1 protein, human; D043562:Receptors, G-Protein-Coupled; D018000:Receptors, Peptide; D007987:Gonadotropin-Releasing Hormone; D011374:Progesterone; D007986:Luteinizing Hormone; D012065:Relaxin