PDGF-CC protects brain cortical neurons from ischemia-induced neuronal death. (A) Western blotting detected PDGF-CC expression in brain cortex as several forms because of differential proteolytic processing. (B and C) PDGF-CC protein CSF injection decreased stroke volume, whereas CSF injection of PDGF-CC neutralizing antibody (anti–PDGF-CC) enlarged stroke volume (n = 11 or 13 mice). (D and E) PDGF-CC protein pretreatment by cortex injection decreased stroke volume significantly (n = 10 mice). (F) PDGF-C–deficient mice displayed greater stroke volume than that of wild-type mice (n = 8 mice). (G and H) Real-time PCR showed up-regulated expression of many neurotrophic/survival factors in brain cortex (G, n = 6 mice) and in isolated primary cortical neurons (H, n = 4 mice) after PDGF-CC treatment. (I) PDGF-CC treatment inhibited the expression of numerous apoptotic/cell death–related genes in brain cortex (n = 8 mice). (J and K) No difference in EB extravasation was found between PDGF-C–deficient and wild-type mice in normal brains (J, n = 10 mice) or brains with MCAO (K). (L and M) PDGF-CC CSF injection did not increase blood vessel permeability in normal brain (L, n = 8 mice) or in brains with MCAO (M, n = 8 mice). *, P < 0.05; **, P < 0.01. The data are represented as means ± SEM of the number of determinations. All experiments were repeated independently one to three times with similar results. Representative images (A, B, and D) and experiments are shown.