Figure 4.

Involvement of constrictor prostanoids in VPC31143-induced contraction. A) Reduced vasoconstrictor effects of 10 μM VPC31143 in AA segments prepared from COX1-KO and TP-KO mice as compared with WT animals. ****P < 0.0001 vs. the corresponding Ctrl; 1-way ANOVA with Tukey’s post hoc test (n = 8–23 vessels obtained from 5–16 animals). B) VPC31143 treatment markedly increased TXA₂ release in COX1-Ctrl TA segments, whereas COX1-KO vessels showed diminished basal rate of TXA₂ production that did not increase in response to VPC31143. In contrast, basal and VPC31143-stimulated TXA₂ release from vessels of TP-KO mice showed no difference compared with TP-Ctrl vessels. **P < 0.01, ****P < 0.0001 vs. before VPC; ^###P < 0.001, ^####P < 0.0001 vs. corresponding COX1 Ctrl; 2-way ANOVA with Bonferroni’s post hoc test (n = 3–7).