In adult male rats, IGFBP-2 (1 μg/kg, i.v.)increased the density of mature dendritic spines and total spine density in the DG and medial prefrontal cortex, which is the underlying mechanisms explaining the therapeutic-like effects of IGFBP-2 in post-traumatic stress disorder (PTSD) (126). The gene discussed is IGFBP2; the disease is post-traumatic stress disorder.