Mitochondrial fusion and fission in myometrium. Relative gene expression level of OPA1, normalised on β-actin (A), according to PCR analysis. Protein level of OPA1 (L- and S-forms: L-upper band, S-lower band) (B), MFN1 and MFN2 (D), DRP1 (E) in myometrium from normal and preeclamptic pregnancies: late-onset PE – loPE, early-onset PE – eoPE (n = 10 for each group), according to western blot analysis (left side – membrane staining, right side – protein level relative to β-actin). Ratio of OPA1-L to OPA1-S levels (C). β-actin was used as a loading control (F). *p < 0.05 versus control.