Figure 6

(A) Knockdown of apelin/APJ, APJ, MEF2A/C or Gα13 in HUVECs leads to decreased mRNA expression of validated and putative MEF2 target genes. *P<0.05 for each knockdown condition compared to control. (B) Transcripts decreased in HUVECs subjected to apelin-APJ, APJ, MEF2A/C or Gα13 knockdown are also significantly decreased in E10.5 Apj−/− embryos. *P<0.05 vs. wildtype. (C) Isolated heart ECs from Apj−/− mice demonstrate decreased expression of gene transcripts identified from the microarray analyses. *P<0.05, **P<0.01 and ***P<0.001. (D) KLF2 expression is significantly induced by rosuvastatin in isolated heart ECs from wildtype mice but not from Apj−/− mice. ***P<0.001 vs. all other conditions. (E) Expression of CX37 and CX40 are decreased in HUVECs subjected to APJ knockdown. (F) Cx37 and Cx40 in CD31 staining ECs of the dorsal aorta (white arrows) are decreased in E10.5 Apj−/− embryos (n=4–5 embryos per group). Cx37/40 staining is shown in red, CD31 is shown in green, and DAPI is shown in blue. Bar indicates 80 µm. (G) Decreased expression of Cx37 and Cx40 in heart ECs of Apj−/− mice.