Figure 1.

A, Acute effect of intravenous infusion of acetylcholine (ACh) or increasing doses of G-1 (41.2 ng/kg, 412 ng/kg, 4.12 ug/kg and 20.6 ug/kg) into normotensive Sprague Dawley rats. Y axis values are expressed as percent change of mean arterial pressure. G-1 produced a dose-dependent reduction in blood pressure of 2.6±2%, 10±1%, 13±1%, and 13.5±2.2%, respectively. *P<0.05 vs. control.

B, Acute vascular effects of solvent control (ethanol, 0.1%, CTL) and GPER-agonist G-1 (1 μmol/L) on vascular tone in rat mesenteric resistance arteries. Arteries were preconstricted with UTP to induce a stable contraction plateau and exposed to ETOH or G-1, and changes in tone were recorded. At 40 minutes, G-1, reduced vascular tone by 29±4%. n=3-4/group. *P<0.05 vs. control.

C, Acute vascular effects of solvent control, 17β-estradiol, or GPER-agonist G-1 on vascular tone in human internal mammary arteries. Arteries were preconstricted with prostaglandin F_2α to induce a stable contraction plateau and exposed to solvent control (ethanol 0.3%, CTL), 17β-estradiol or G-1 (both at 3 μ mol/L), and changes in tone were recorded. Both 17β-estradiol and G-1 induced a relaxant response; however, the relaxation in response to G-1 was more potent *P<0.05 vs. CTL, **P<0.05 vs. 17β-estradiol, unpaired t-test, n=4-7/group.

D, Acute vascular effects of solvent control (ethanol, 0.3%, CTL), 17β-estradiol, or GPER-agonist G-1 on vascular tone in mouse carotid arteries. Arteries were preconstricted with prostaglandin F_2α to induce a stable contraction plateau and exposed to 17β-estradiol or G-1 (both at 3 μ mol/L), and changes in tone were recorded. G-1, but not 17β-estradiol, reduced vascular tone by 44±5%. *P<0.05 vs. solvent, unpaired t-test, n=4-7/group;

E, Acute vascular effects of solvent control (ethanol, 0.3%, CTL), 17β-estradiol, or GPER-agonist G-1 on vascular tone in mouse carotid arteries. Arteries were preincubated with 17β-estradiol or G-1 (both at 3 μ mol/L) for 45 minutes and then exposed to serotonin (5HT, 1 μmol/L). G-1 reduced contraction by 39%. *P<0.05 vs. solvent, unpaired t-test, n=4-8/group.

F, Left panel: representative original recordings of the effects of intracellular ligand injection on intracellular calcium concentrations in Fura-2-loaded human aortic vascular smooth muscle cells. Solvent had only small effects on intracellular calcium concentrations. Serotonin (5-HT) produced a strong calcium mobilization response. Intracellular injection of G-1 produced a fast and transient increase in calcium concentration, and pretreatment with G-1 completely blunted the subsequent 5-HT-induced changes in intracellular calcium. Right panel: averaged data of 4 experiments. *P<0.05 vs. 5-HT alone, paired t-test, n=4/group.

G, Effects of G-1 (10 and 100 nmol/L) on ERK-1/2 phosphorylation in human vascular smooth muscle cells expressing only GPER by Western blot. Left panel, representative example; Right, averaged, n=8/group. *P<0.05 vs. solvent, unpaired t-test.

H, Effects of GPER agonists G-1 and ICI 182,780 on serum-stimulated cell proliferation in human vascular smooth muscle cells expressing only GPER. Both agonists reduced cell proliferation between 60% and 80% at concentration of 1000 nmol/L. *P<0.05 vs. solvent, n=6/group