Peroxisome proliferator perfluordecanoic acid (PFDA) inhibits the Leydig cell steroidogenesis by affecting PBR mRNA stability, thus inhibiting PBR expression, cholesterol transport into the mitochondria and subsequent steroid formation. A cytoplasmic protein, PRAX-1 （peripheral benzodiazepine receptor-associated protein 1), is found to specifically interact with PBR.
