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PubMed · 9316013

Estradiol reduction of alpha 2-adrenoceptor binding in female rat cortex is correlated with decreases in alpha 2A/D-adrenoceptor messenger RNA.

G B Karkanias·C S Li·A M Etgen
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Abstract

We developed a quantitative RNAse protection assay for alpha 2A/D-adrenoceptor messenger RNA in rats to test the hypothesis that decreases in cortical alpha 2-adrenoceptor binding observed following estrogen treatment of ovariectomized rats correlate with reduced levels of messenger RNA encoding the predominant alpha 2-adrenoceptor subtype expressed in cortex. Estradiol treatment for 48 h reduced cortical alpha 2A/D-adrenoceptor messenger RNA by approximately 50% when compared to ovariectomized, oil-treated control animals. Estradiol down-regulation of alpha 2A/D-adrenoceptor messenger RNA was accompanied by a significant decrease in cortical alpha 2-adrenoceptor density, as measured by 3H-RX821002 binding. Estrogen treatment did not alter alpha 2A/D-adrenoceptor messenger RNA or alpha 2-adrenoceptor binding in female rat hypothalamus-preoptic area. This study provides the first evidence that estradiol regulates expression of postsynaptic alpha 2-adrenoceptors in female rat frontal cortex, suggesting a possible molecular substrate for hormonal modulation of cognitive function.

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Adrenergic alpha-AntagonistsAnimalsCerebral CortexDown-RegulationEstradiolFemaleIdazoxanOvariectomyRNA, MessengerRatsReceptors, Adrenergic, alphaReference ValuesJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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G B Karkanias, C S Li, A M Etgen. 1997. Estradiol reduction of alpha 2-adrenoceptor binding in female rat cortex is correlated with decreases in alpha 2A/D-adrenoceptor messenger RNA.. https://doi.org/10.1016/s0306-4522(97)00359-x

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