Figure 2: Effect of hydrogen-rich water (HRW) on water restriction-induced stress protein in placenta of placental stress rats induced by water restriction (immunohistochemistry detection). Note: Water restriction-induced stress proteins were widely distributed in the decidual cells, cytotrophoblasts, syncytiotrophoblasts, and the villous stromal cells. The strongest positive staining of stress proteins were usually observed in water restriction group (WR), in addition to the strongest staining of superoxide dismutase (SOD), was seen in control group (CG). The staining intensity of hydrogen-rich water group (HW) was generally in between. (A) Immunohistochemistry staining of SOD, angiotensin II type 1 receptor (AT1R), nuclear factor κB (NFκB), malondialdehyde (MDA) and 8-hydroxydeoxyguanosine (8-OhdG). ↑: The positive staining. Scale bars: 20 μm. (B) The average optical density of SOD, AT1R, NFκB, MDA and 8-OHdG immunopositive cells among different groups on D17. Data are shown as the mean ± SEM, and analyzed by repeated measures analysis of variance. *P < 0.05, vs. CG group; #P < 0.05, vs. WR group.