Fig. 1.
Validation of EP4 deficiency in VSMCs. (A) Schematic showing of the floxed EP4 allele (EP4f/f) and Cre recombinase modified allele (EP4f/f_Cre+). The locations of two LoxP sites flanking the exon 2 of the EP4 gene were shown. P1 and P2 were primers designed to detect the presence or absence of the exon 2. (B) PCR validation of WT, EP4f/+, and EP4f/f alleles (Upper) and Cre recombinase transgene (Lower). The band with 243 or 344 bp represents the WT allele and floxed allele, respectively. The band with 370 bp indicates the presence of the SMMHC-Cre transgene. (C) Immunohistochemistry showing the absence of EP4 protein expression was in the aortic SM layer of the VSMC-EP4−/− mouse. (D) Expression levels of four EP receptors in the thoracic aortas of EP4f/f and VSMC-EP4−/− mice. n = 5–6; ***P < 0.001 vs. EP4f/f.