Immunocytochemical demonstration of estrogen receptor beta in human periodontal ligament cells.

Two transcription associated estrogen receptor (ER) subtypes have been identified and named ERalpha and ERbeta. In the present study we investigate the expression of these ER subtypes in cultured human periodontal ligament (PDL) cells by immunocytochemistry. ERbeta immunoreactivity was observed in the nuclei of about 40% of the PDL cells, while no ERalpha immunoreactivity was detected. In human breast cancer MCF-7 cells, serving as positive controls, both ERalpha and ERbeta immunoreactivities were demonstrated. No immunoreactivity was observed after omission of the primary antibodies. This study suggests that estrogen acts on gene transcription preferentially via ERbeta in human PDL cells.