该PGR Monoclonal Antibody. The steroid hormones and their receptors are involved in the regulation of eukaryotic gene expression and affect cellular proliferation and differentiation in target tissues. Progesterone receptor isoform B (PRB) is involved activation of c-SRC/MAPK signaling on hormone stimulation.Isoform A: inactive in stimulating c-Src/MAPK signaling on hormone stimulation.Isoform 4: Increases mitochondrial membrane potential and cellular respiration upon stimulation by progesterone.