title: Adrenomedullin expression in rat uterus is correlated with plasma estradiol.
abstract: Levels of expression of adrenomedullin (AM) in the uterus have been reported to vary with the reproductive cycle. This study examines the relationships among uterine AM mRNA, the stage of the estrous cycle, and circulating estradiol and progesterone in cycling rats and in ovariectomized (OVX) rats without or with estrogen replacement (ER). Strong AM mRNA, AM immunoreactivity, and pro-AM NH2-terminal 20 peptide (PAMP) immunoreactivity were observed in endometrial stroma by use of in situ hybridization and immunocytochemistry. Endometrial expression was particularly intense at proestrus and estrus, with weaker expression in the myometrium. By RNase protection assay, significant differences in AM mRNA between the stages of the estrous cycle could not be established. However, levels of AM mRNA were positively correlated with plasma estradiol in cycling rats (r = 0.56, P < 0.005) and in OVX and ER rats (r = 0.92, P < 0.001) and were not correlated with plasma progesterone. Levels of AM mRNA were significantly reduced after OVX compared with cycling rats, and ER restored AM mRNA to levels equivalent to those seen at the peak of the cycle (proestrus). In conclusion, although AM expression in the uterus varies throughout the estrous cycle, it is more closely correlated with circulating estradiol levels than with the stage of the cycle itself.
authors.affiliation: Department of Medicine, Christchurch School of Medicine, Christchurch 8001, New Zealand. vicky.cameron@chmeds.ac.nz
authors.forename: Vicky A
authors.initials: VA
authors.lastname: Cameron
authors.forename: Dominic J
authors.initials: DJ
authors.lastname: Autelitano
authors.forename: John J
authors.initials: JJ
authors.lastname: Evans
authors.forename: Leigh J
authors.initials: LJ
authors.lastname: Ellmers
authors.forename: Eric A
authors.initials: EA
authors.lastname: Espiner
authors.forename: M Gary
authors.initials: MG
authors.lastname: Nicholls
authors.forename: A Mark
authors.initials: AM
authors.lastname: Richards
mesh_terms: D053607:Adrenomedullin; D000818:Animals; D004717:Endometrium / Q000378:metabolism; D004958:Estradiol / Q000097:blood*; D004967:Estrogens / Q000494:pharmacology; D004971:Estrus / Q000378:metabolism; D005260:Female; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases / Q000378:metabolism; D008597:Menstrual Cycle / Q000378:metabolism; D009215:Myometrium / Q000378:metabolism; D010052:Ovariectomy; D010455:Peptides / Q000235:genetics / Q000378:metabolism*; D011359:Proestrus / Q000378:metabolism; D011374:Progesterone / Q000097:blood; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D014599:Uterus / Q000378:metabolism*
chemical_list: D004967:Estrogens; D010455:Peptides; D012333:RNA, Messenger; D053607:Adrenomedullin; D011374:Progesterone; D004958:Estradiol; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases