Differential mass spectrometry of rat plasma reveals proteins that are responsive to 17β-estradiol and a selective estrogen receptor modulator PPT

Estrogens are a class of steroid hormones that interact with two related but distinct nuclear receptors, estrogen receptor (ER) alpha and beta. To identify potential ER biomarkers, we profiled the rat plasma glycoproteome after treatment with vehicle or 17 beta-estradiol (E2) or an ER alpha-selective agonist PPT by differential mass spectrometry. Our comparative proteomic experiment identifies novel E2- and PPT-responsive proteins, such as serine protease inhibitor family members.