Placental growth factor (PGF) is a member of the VEGF (vascular endothelial growth factor) subfamily - a key molecule in angiogenesis and vasculogenesis, in particular during embryogenesis. The main source of PGF during pregnancy is the placental trophoblast. PGF is also expressed in many other tissues, including the villous trophoblast.
Enhanced expression of PGF in hematoma fluid suggests the involvement of this factor in the mechanisms of inflammation and angiogenesis in chronic subdural hematoma (CSDH). Furthermore, a reduced ratio of sVEGFR-1 to PGF in hematoma fluid is consistent with the proangiogenic capacity of CSDH. Future studies are warranted to clarify the precise role of PGF and sVEGFR-1 in CSDH 1)