PPM1F and depressive disorder: However, in the current study, it was interesting to find that the expression levels of PPM1F in depressed mice decreased in the mPFC, another morbigenous region underlying the pathophysiology of depression,2, 6, 40 and this result was consistent with the another research that the reduced expression levels of PPM1F in mPFC was observed in the mice subjected to acute immobilization stress.14