title: Sexual dimorphism in the content of progesterone and estrogen receptors, and their cofactors in the lung of adult rats.
abstract: Progesterone and estradiol play an important role in the regulation of lung functions such as ventilation and vasoconstriction. The genomic actions of progesterone and estradiol are mediated by their nuclear receptors: progesterone receptors (PR) and estrogen receptors (ER). These actions are linked to interactions between steroid receptors and some cofactors that function as coactivators or corepressors. In this work we determined the content of PR isoforms, ER-beta, one coactivator (SRC-1), and one corepressor (SMRT) in the lung of both female rats during the estrous cycle and intact males by Western blot. The rat lung presented a higher content of PR-A than that of PR-B during the estrous cycle. The highest content of both PR isoforms was observed on the day of proestrus whereas the lowest one was found on the day of estrus. In contrast, the content of ER-beta was the lowest on the day of proestrus and it increased at estrus. The content of SRC-1 and SMRT increased on the day of diestrus. SRC-1 content decreased at proestrus and estrus, while SMRT content decreased at proestrus and increased again at estrus. In the lung of adult male rats the content of PR isoforms, ER-beta and SMRT was lower than in that of females, whereas the content of SRC-1 was similar in both sexes. Our results suggest a sexual dimorphism in the content of PR, ER-beta, and SMRT in the rat lung as well as a relation of their content to the physiological levels of progesterone and estradiol.
authors.affiliation: Departamento de Biología, Facultad de Química, Universidad Nacional Autónoma de México, Ciudad Universitaria, Coyoacán 04510, México, D.F., Mexico.
authors.forename: Aliesha
authors.initials: A
authors.lastname: González-Arenas
authors.forename: Teresa
authors.initials: T
authors.lastname: Neri-Gómez
authors.forename: Christian
authors.initials: C
authors.lastname: Guerra-Araiza
authors.forename: Ignacio
authors.initials: I
authors.lastname: Camacho-Arroyo
mesh_terms: D000818:Animals; D004268:DNA-Binding Proteins / Q000378:metabolism*; D004958:Estradiol / Q000378:metabolism; D030762:Estrous Cycle / Q000502:physiology; D005260:Female; D051548:Histone Acetyltransferases; D006801:Humans; D008168:Lung / Q000033:anatomy & histology / Q000502:physiology*; D008297:Male; D056985:Nuclear Receptor Co-Repressor 2; D056920:Nuclear Receptor Coactivator 1; D011247:Pregnancy; D011374:Progesterone / Q000378:metabolism; D020033:Protein Isoforms / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D011960:Receptors, Estrogen / Q000378:metabolism*; D011980:Receptors, Progesterone / Q000378:metabolism*; D012097:Repressor Proteins / Q000378:metabolism*; D012727:Sex Characteristics; D014157:Transcription Factors / Q000378:metabolism*
chemical_list: D004268:DNA-Binding Proteins; C539130:NCOR2 protein, human; C539132:Ncor2 protein, rat; D056985:Nuclear Receptor Co-Repressor 2; D020033:Protein Isoforms; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; D012097:Repressor Proteins; D014157:Transcription Factors; D011374:Progesterone; D004958:Estradiol; D051548:Histone Acetyltransferases; C538859:NCOA1 protein, human; D056920:Nuclear Receptor Coactivator 1