Lost OTR Expression and HIF-1α Self-protection in Myometrium of Intractable Postpartum Hemorrhage

Abstract Objective: In intractable postpartum hemorrhage(IPPH), uterotonic lost efficacy in myometrum contraction formation. While the key target in uterotonic, OTR(oxytocin receptor) and internal environment in myometrum might have some changes when IPPH. Methods: Three groups of myometrial tissue at different contraction states were collected:(1) term not at labour (TNL) group(10 cases); (2) term at labour (TAL) group(10 cases);(3) intractable postpartum hemorrhage(IPPH) group(10 cases).Expressions of OTR and internal environment markers(ASIC1a ,HIF1α, GlUT, FATP and apoptosis ) were compared in 3 groups by Immunoreactivity Scores method. Results: The expression of OTR in myometrium in IPPH group was 100% negative ,compared to 30%,20% in TNL and TAL group(p < 0.05).70% positive HIF-1α expression in TNL group increased to 80% in TAL group,but decreased to 20% in IPPH group(P<0.05). While the positive expressions of ASIC1a, FATP and GLUT in three groups all had no significant difference.But the apoptosis related markers Bax,caspase-3 and caspase-9 positive expressions in IPPH were significantly all decreased(10%,10%,0%) compared to TNL and TAL group,compared to a high positive expression of Bcl-2 in 3 groups.Conclusion: OTR expression and HIF-1α self-protection might be lost in myometrium of IPPH, which could lead to uterotonic lost efficacy and conservative treatment failure.