Postovariectomy weight gain in female rats is reversed by estrogen receptor alpha agonist, propylpyrazoletriol.
OBJECTIVE
The objective of this study was to distinguish the role of specific estrogen receptors (ERs), ERalpha and ERbeta, on body weight regulation using a rat model of weight gain subsequent to menopause.


METHODS
Ovariectomized rats were utilized as the animal model to simulate the postmenopause weight gain. The rats were ovariectomized and subcutaneously injected daily with vehicle, estradiol-17beta (E2), propylpyrazoletriol (PPT; ERalpha agonist) and diarylpropionitrile (DPN; ERbeta agonist). To further control for the possible effect of estrogen secreted from adrenals, a second experiment was conducted during which the rats were adrenalectomized and ovariectomized.


RESULTS
Ovariectomy significantly increased (P < .05) body weight, whereas treatment of ovariectomized rats with E2 and PPT, but DPN decreased (P < .05) body weight. The results from the second study with ovariectomized/adrenalectomized rats were consistent with the first experiment.


CONCLUSIONS
These results suggest that the activation of ERalpha is important in regulating body weight.
Wegorzewska
Iga N
IN
Department of Obstetrics and Gynecology, Uniformed Services University of the Health Sciences, Bethesda, MD, USA.
Walters
Katy
K
Weiser
Michael J
MJ
Cruthirds
Danette F
DF
Ewell
Emily
E
Larco
Darwin O
DO
Handa
Robert J
RJ
Wu
T John
TJ
D000818:Animals; D004195:Disease Models, Animal; D004958:Estradiol / Q000494:pharmacology; D047628:Estrogen Receptor alpha / Q000819:agonists; D047629:Estrogen Receptor beta / Q000819:agonists; D004967:Estrogens / Q000494:pharmacology; D005260:Female; D009570:Nitriles / Q000494:pharmacology; D010052:Ovariectomy / Q000009:adverse effects*; D010636:Phenols; D011422:Propionates / Q000494:pharmacology; D011720:Pyrazoles / Q000494:pharmacology*; D051381:Rats; D020318:Rats, Long-Evans; D011960:Receptors, Estrogen / Q000819:agonists*; D015430:Weight Gain / Q000187:drug effects*
C486182:2,3-bis(4-hydroxyphenyl)-propionitrile; D047628:Estrogen Receptor alpha; D047629:Estrogen Receptor beta; D004967:Estrogens; D009570:Nitriles; D010636:Phenols; D011422:Propionates; D011720:Pyrazoles; D011960:Receptors, Estrogen; C486184:4,4',4''-(4-propyl-((1)H)-pyrazole-1,3,5-triyl) tris-phenol; D004958:Estradiol