HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) All Versions of this Article: 293/6/R2194    most recent 00385.2007v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in ISI Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Google Scholar Articles by Santollo, J. Articles by Eckel, L. A. PubMed PubMed Citation Articles by Santollo, J. Articles by Eckel, L. A.

APPETITE, OBESITY, DIGESTION, AND METABOLISM

Acute activation of ER decreases food intake, meal size, and body weight in ovariectomized rats

Program in Neuroscience and Department of Psychology, Florida State University, Tallahassee Florida

Estradiol exerts many of its actions by coupling with two nuclear estrogen receptor (ER) proteins, ER, and ERβ.While the acute, anorexigenic effect of estradiol appears to involve such a mechanism, the relative contributions of ER and ERβ are equivocal. To address this problem, food intake was monitored in ovariectomized (OVX) rats following acute administration of a selective ER agonist (4,4',4''-(4-propyl-[1H]-pyrazole-1,3,5-triyl)trisphenol, PPT; dose range = 0–200 µg), a selective ERβ agonist (2,3-bis(4-hydroxyphenyl)-propionitrile, DPN; dose range = 0–600 µg), and a physiological (4 µg) dose of estradiol benzoate (EB). While PPT-treated rats displayed dose-dependent decreases in daily food intake and body weight, neither of these measures was influenced by any dose of DPN. In addition, DPN failed to modulate the anorexigenic effect of PPT when the two ER agonists were coadministered. Meal pattern analysis revealed that the anorexigenic effect of 75 µg PPT (a dose of PPT that produced a similar decrease in daily food intake as 4 µg EB) was mediated by a decrease in meal size, not meal number. Thus, PPT, like EB and endogenous estradiol, decreases food intake by selectively affecting the controls of meal size. The finding that acute administration of 75 µg PPT failed to induce a conditioned taste aversion suggests that the anorexigenic effect of this dose of PPT is not secondary to malaise. Taken together, our findings demonstrate that selective activation of ER decreases food intake, body weight, and meal size in the ovariectomized rat.

4,4',4''-(4-propyl-[1H]-pyrazole-1,3,5-triyl)trisphenol; 2,3-bis(4-hydroxyphenyl)-propionitrile; food intake; estradiol