NRG1 and pneumocystosis: However, in neurons from NRG1-knockout mice, the prevention effect of olanzapine on the PCP-induced reduction in p-Akt and p-GSK3 expression disappeared (Fig. 6a,c,e), indicating that NRG1 is a critical mediator for the effect of olanzapine on preventing PCP-induced reduction in Akt-GSK signaling.