PTGS2 and depressive symptom measurement: Klawonn et al. (62) found that the COX-2/activation of the PGs/EPR pathway increased neuronal peak potential spacing, decreased membrane electrical resistance and posterior hyperpolarization (fAHP), and simultaneously inhibited the GABA and DA signaling pathways, which in turn inhibited DA transmitter production and transmission, thereby triggering negative mood and depression (61).