Expression of functional luteinizing hormone (LH) receptor and its messenger ribonucleic acid in bovine endometrium: LH augmentation of cAMP and inositol phosphate in vitro and human chorionic gonadotropin (hCG) augmentation of peripheral prostaglandin in vivo.
Bovine endometrium contains LH/hCG binding sites and LH increases endometrial production of prostaglandin H synthase-2 (PGHS-2) and prostaglandin synthesis. This study showed that uterine endometrium contained both LH receptor mRNA transcript and a 93-kDa immunoreactive protein that bound to anti-rat LH receptor antibody. LH receptor and its mRNA were expressed maximally in the endometrium of cows from the luteal phase compared to the follicular phase of the estrous cycle. Furthermore, there was a response shown when incubation of endometrial minces from both pre-estrus/estrus and luteal phase (but not post-ovulatory phase) with LH or oxytocin (20 ng/ml) that resulted in a significant (p<0.02) increase in cAMP and total inositol phosphates. When Day 15 cows were injected i.v. with 3000 units hCG, the increase in peripheral 13,14-dihydro-15-keto PGF(2alpha) was 2.5-fold higher than saline controls or oxytocin. We conclude that LH stimulates endometrial cAMP and total inositol phosphates which results in increased formation of uterine PGHS-2 similar to LH effect on ovarian PGHS-2. The increased 13,14-dihydro-15-keto PGF(2alpha) production induced in vivo by injections of hCG indicates that LH may have a reinforcing role in luteolysis.
Shemesh
M
M
Department of Hormone Research, Kimron Veterinary Institute, Bet Dagan 12, Israel. mshem@vs.moag.gov.il
Mizrachi
D
D
Gurevich
M
M
Shore
L S
LS
Reed
J
J
Chang
S M
SM
Thatcher
W W
WW
Fields
M J
MJ
D000818:Animals; D001483:Base Sequence; D015153:Blotting, Western; D002417:Cattle; D006063:Chorionic Gonadotropin / Q000008:administration & dosage*; D000242:Cyclic AMP / Q000378:metabolism / Q000494:pharmacology; D051546:Cyclooxygenase 2; D015237:Dinoprost / Q000031:analogs & derivatives* / Q000032:analysis / Q000096:biosynthesis; D004717:Endometrium / Q000737:chemistry*; D005260:Female; D019205:GTP-Binding Protein alpha Subunits, Gs / Q000235:genetics; D019204:GTP-Binding Proteins / Q000235:genetics; D015870:Gene Expression / Q000187:drug effects; D007295:Inositol Phosphates / Q000378:metabolism; D007527:Isoenzymes / Q000032:analysis; D007986:Luteinizing Hormone / Q000008:administration & dosage*; D008969:Molecular Sequence Data; D010053:Ovary / Q000187:drug effects / Q000378:metabolism; D010121:Oxytocin / Q000494:pharmacology; D011451:Prostaglandin-Endoperoxide Synthases / Q000032:analysis; D011453:Prostaglandins / Q000378:metabolism; D012333:RNA, Messenger / Q000032:analysis* / Q000737:chemistry; D011974:Receptors, LH / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017385:Sequence Homology; D010738:Type C Phospholipases / Q000378:metabolism; D014599:Uterus / Q000187:drug effects / Q000378:metabolism
D006063:Chorionic Gonadotropin; D007295:Inositol Phosphates; D007527:Isoenzymes; D011453:Prostaglandins; D012333:RNA, Messenger; D011974:Receptors, LH; C008228:15-keto-13,14-dihydroprostaglandin F2alpha; D010121:Oxytocin; D007986:Luteinizing Hormone; D015237:Dinoprost; D000242:Cyclic AMP; D051546:Cyclooxygenase 2; D011451:Prostaglandin-Endoperoxide Synthases; D010738:Type C Phospholipases; D019204:GTP-Binding Proteins; D019205:GTP-Binding Protein alpha Subunits, Gs