title: Estrogen receptor-alpha and -beta are expressed throughout postnatal development in the rat and rabbit growth plate.
abstract: Estrogen regulates skeletal growth and promotes epiphyseal fusion. To explore the mechanisms underlying these effects we investigated the expression of estrogen receptor-alpha (ERalpha) and -beta (ERbeta) in rat and rabbit growth plates during postnatal development, using immunohistochemistry. Immunoreactivity for ERalpha and ERbeta was observed in resting zone and proliferative zone chondrocytes at all ages studied for both rat (7, 14, 28 and 70 days of age) and rabbit (1, 7, 28 and 120 days of age). In the rat distal humerus and the rabbit proximal tibia, expression of both receptors in the hypertrophic zone was minimal at early ages, increasing only at the last time point prior to epiphyseal fusion. Expression was rarely seen in the hypertrophic zone of the rat proximal tibia, a growth plate that does not fuse until late in life. Therefore, we conclude that ERalpha and ERbeta are both expressed in the mammalian growth plate. The temporal and anatomical pattern suggests that ER expression in the hypertrophic zone in particular may play a role in epiphyseal fusion.
authors.affiliation: Pediatric Endocrinology Unit, Department of Woman and Child Health, Karolinska Institutet, Stockholm, Sweden. ola.nilsson@kbh.ki.se
authors.forename: Ola
authors.initials: O
authors.lastname: Nilsson
authors.forename: V
authors.initials: V
authors.lastname: Abad
authors.forename: D
authors.initials: D
authors.lastname: Chrysis
authors.forename: E M
authors.initials: EM
authors.lastname: Ritzén
authors.forename: L
authors.initials: L
authors.lastname: Sävendahl
authors.forename: J
authors.initials: J
authors.lastname: Baron
mesh_terms: D000375:Aging / Q000502:physiology*; D000818:Animals; D019902:Chondrocytes / Q000737:chemistry / Q000378:metabolism; D047628:Estrogen Receptor alpha; D047629:Estrogen Receptor beta; D005260:Female; D006132:Growth Plate / Q000737:chemistry / Q000378:metabolism*; D006811:Humerus; D007150:Immunohistochemistry / Q000379:methods; D008297:Male; D011817:Rabbits; D051381:Rats; D017207:Rats, Sprague-Dawley; D011960:Receptors, Estrogen / Q000032:analysis / Q000378:metabolism*; D013977:Tibia
chemical_list: D047628:Estrogen Receptor alpha; D047629:Estrogen Receptor beta; D011960:Receptors, Estrogen