title: Comparative expression and distribution of c-fos, estrogen receptoralpha (eralpha), and p38alpha in the uterus of rats, monkeys, and humans.
abstract: The uterine cellular expression and distribution of c-fos, ERalpha and p38alpha was compared in humans, nonhuman primates, and rats using immunohistochemistry. ERalpha and c-fos were present in the glandular (GE) and luminal epithelial cells (LE) of humans and nonhuman primates, with differing expression patterns evident between proliferative and secretory cycle phases. In rats, the highest and lowest expression of c-fos was present during proestrus and estrus, respectively, in the LE and GE. The most intense ERalpha staining in rats was observed during proestrus in the GE, while the least intense staining was seen in the LE during proestrus. Strong LE and GE expression of p38alpha was present in rats in all stages of the estrous cycle and during the proliferative phase in both humans and nonhuman primates. No p38alpha expression was observed during the secretory phase in either humans or nonhuman primates. Our work suggests that c-fos, ERalpha and p38alpha (a) are primarily expressed during the proliferative phase, but not the secretory phase and exhibit interspecies expression variability, and (b) rats exhibit cyclic changes in the expression of c-fos and ERalpha.
authors.affiliation: Worldwide Safety Sciences, Pfizer Global Research and Development, Ann Arbor, Michigan, 48105, USA. zaher.radi@pfizer.com
authors.forename: Zaher A
authors.initials: ZA
authors.lastname: Radi
authors.forename: Nasir K
authors.initials: NK
authors.lastname: Khan
mesh_terms: D000818:Animals; D047628:Estrogen Receptor alpha / Q000235:genetics / Q000378:metabolism*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008252:Macaca fascicularis; D048308:Mitogen-Activated Protein Kinase 14 / Q000235:genetics / Q000378:metabolism*; D016760:Proto-Oncogene Proteins c-fos / Q000235:genetics / Q000378:metabolism*; D051381:Rats; D014599:Uterus / Q000201:enzymology* / Q000378:metabolism*
chemical_list: D047628:Estrogen Receptor alpha; D016760:Proto-Oncogene Proteins c-fos; D048308:Mitogen-Activated Protein Kinase 14