Estrogen dependent expression of sex hormone binding globulin in PC 12 cells

Rat pheochromocytoma PC 12 cells are known to develop features of dopaminergic neurons upon treatment with nerve growth factor. They express in part estrogen receptors α and β, and G-protein coupled receptor 30. Estrogens promote development of these cells and exert neuroprotective effects. Here we treated differentiated PC 12 cells with physiological concentrations of 17-β-estradiol. We observed with immunocytochemistry cytoplasmic staining for SHBG in a portion of these cells Double immunostaining for estrogen receptor-β revealed that some PC 12 cells contained both antigens. Numbers of estrogen receptor-β positive cells were significantly higher after estradiol treatment; an effect that was not altered by pretreatment of cultures with tamoxifen. With reverse transcriptase polymerase chain reaction we observed sex hormone binding globulin encoding transcripts indicating intrinsic expression of the steroid binding globulin. We conclude that estrogen treatment induces SHBG expression in differentiated PC12.