Fig. 4. E2 inhibited Src activation in 5-HT-stimulated rat aortic smooth muscle and in HEK293T cells.

a Aortic tissues from 10-week-old rats treated with 5-HT in combination with vehicle, genistein (Gen) or E2 were subjected to Western blotting for phospho-Src (p-Src) or Src. β-Tubulin was used as a loading control. b The relative band intensity shown in panel a was quantified with the use of ImageJ software. The value of pSrc was normalized to that of Src, and the value of 5-HT-treated cells was set to 1.0. Data represent the mean ± SD (n = 3). *p < 0.05. c Protein lysates from HEK293T cells that were non- or mock-treated (DMSO) or treated with 100 μM genistein (Gen), 100 μM E2, or Gen plus E2 for 10 min after 24-h starvation were analyzed by Western blotting with an antibody against p-Src or Src. β-Tubulin was used as a loading control. d The relative band intensity shown in panel c was quantified with ImageJ software. The value of pSrc was normalized to that of Src, and the value of DMSO-treated cells was set to 1.0. Data represent the mean ± SD (n = 3). *p < 0.05. e A working model summarizing the regulatory mechanism of serotonin-induced vasoconstriction by estradiol