title: Effect of ovariectomy on renal estrogen receptor-alpha and estrogen receptor-beta in young salt-sensitive and -resistant rats.
abstract: This study evaluated the effect of ovariectomy on renal estrogen receptor (ER)-alpha and ERbeta expression in young female Dahl salt-sensitive and salt-resistant rats. Our hypothesis was that estrogen depletion results in an imbalance in ERalpha and ERbeta expression in salt-sensitive rats. Rats were subjected to sham surgery (intact), ovariectomy, and ovariectomy with estrogen replacement. Kidneys were harvested 8 weeks later. Western blot was used to measure ERalpha and ERbeta expression in the cortex and medulla. In intact rats, ERalpha was 2.7- and 4.3-fold higher in salt-sensitive compared with salt-resistant rats in the renal cortex and medulla, respectively. In salt-sensitive rats, ovariectomy caused 42% and 52% decreases in ERalpha and 107% and 314% increases in ERbeta in renal cortex and medulla, respectively. In salt-resistant rats, ovariectomy caused 33% and 150% increases in ERalpha and 107% and 100% increases in ERbeta in renal cortex and medulla, respectively. Estrogen replacement did not alter ERalpha but restored ERbeta expression levels similar to levels in intact rats in both salt-sensitive and salt-resistant rats. Thus, estrogen loss had opposite effects on ERalpha in salt-sensitive (downregulation) and salt-resistant rats (upregulation). We propose that the decrease in ERalpha expression in salt-sensitive rats after estrogen loss alters the balance of renal ERs and may play a role in accelerating the development of hypertension and renal damage.
authors: Department of Anesthesiology, University of Texas Health Science Center, 7703 Floyd Curl Dr, San Antonio, TX 78229-3900, USA.
authors: Maria Eugenia Davila
authors: ME
authors: Esqueda
authors: Teresa
authors: T
authors: Craig
authors: Carmen
authors: C
authors: Hinojosa-Laborde
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D015536:Down-Regulation; D047628:Estrogen Receptor alpha / Q000235:genetics / Q000378:metabolism*; D047629:Estrogen Receptor beta / Q000235:genetics / Q000378:metabolism*; D004967:Estrogens / Q000502:physiology*; D005260:Female; D006973:Hypertension / Q000209:etiology / Q000378:metabolism; D007668:Kidney / Q000378:metabolism*; D007672:Kidney Cortex / Q000378:metabolism; D007679:Kidney Medulla / Q000378:metabolism; D010052:Ovariectomy; D051381:Rats; D020303:Rats, Inbred Dahl; D015854:Up-Regulation
chemical_list: D047628:Estrogen Receptor alpha; D047629:Estrogen Receptor beta; D004967:Estrogens