PGR and adrenal gland pheochromocytoma: mPRβ mRNA was drastically increased during NGF-induced neurogenesis in PC12, a rat adrenal pheochromocytoma cell line, whereas the expression of other progesterone receptors such as mPRα, Progesterone Receptor (PR), and PGRMC-1 did not exhibit the same expression profile (Fig. 1e).