Figure 2.

Isometric tension measurement of uterine strips in vitro (n = 6). The process was divided into five periods: (1) T_e for observing spontaneous contraction and baseline setting; (2) T₀ for the period after reagents added; (3) T₁, T₂, and T₃ representing periods of contractile changes following corresponding hypoxic treatment. (A) Changes of AUC and amplitude among the group from T_e to T₃ and the information of waves and experiment settings. During the normoxic period, the chambers were bubbled with mixed gas (95% O₂ + 5% CO₂), whereas 100% N₂ was bubbling for 15 mins into the chambers to create hypoxic condition. (a) Compared group hypoxia to control, the AUC in T₁ (P < 0.05) and T₂ (P < 0.01) was significantly higher, and the amplitude in group hypoxia gradually improved from T₁ to T₃ (P < 0.01). (b) Compared group hypoxia to control, both the AUC and amplitude were dramatically reduced following each hypoxic treatment, especially in T₂ (P < 0.01) and T₃ (P < 0.01). (B) Expression of HIF-1α in isolated uterine strips from groups. ^**P < 0.01.