Regulation of the membrane estrogen receptor-alpha: role of cell density, serum, cell passage number, and estradiol

Article

关键词: PITUITARY-TUMOR CELLS;    MESSENGER-RNA EXPRESSION;    ACTIVATED PROTEIN-KINASE;    NITRIC-OXIDE SYNTHASE;    BREAST-CANCER-CELLS;    RAT PITUITARY;    PLASMA-MEMBRANE;    GLUCOCORTICOID RECEPTOR;    MCF-7 CELLS;    EPITHELIAL-CELLS;   

DOI  :  10.1096/fj.02-0182com

来源: SCIE

【 摘 要 】

We used modified immunocytochemical conditions to quantify a membrane form of estrogen receptor-alpha (mERalpha) in a rat pituitary tumor cell line, GH(3)/B6/F10. We studied the regulation of mERalpha vs. levels of intracellular ERalpha (iERalpha) using our 96-well plate immunoassay. The anti-ERalpha antibody C542 was used to label the ERalpha (via conjugated alkaline phosphatase) in fixed permeabilized (for iERalpha) vs. nonpermeabilized cells (for mERalpha). Expression of mERalpha was highest at low cell densities (<1000 cells/well) and decreased significantly at densities where cellular processes touched, whereas the more abundant iER alpha increased with increasing cell density over the same range. Serum starvation for 48 h caused increases in mER alpha, whereas iER alpha levels showed no significant changes. A large decline in mER alpha and iER alpha levels with cell passage number was observed. Minutes after nM 17 beta-estradiol (E(2)) treatment, a portion of the cells rounded up and detached from the culture plate, whereas nM cholesterol had no such effect. Although E(2) treatment did not change mER alpha levels, the antigen was reorganized from a fine particulate to aggregation into asymmetric large granules of staining. That common culturing conditions favor down-regulation of mER alpha may explain the relatively few reports of this protein in other experimental systems.

【 授权许可】

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