[Mitochondrial tRNA(leu(UUR)) gene mutation and the decreased activity of cytochrome C oxidase in preeclampsia].

OBJECTIVE

To study the effect of mitochondrial tRNA(leu(UUR)) gene mutation at nuecleotide 3243 and the activity of cytochrome C oxidase on the pathogenesis of pregnancy induced hypertension(PIH).

METHODS

57 cases of PIH and 60 normal pregnancy women were detected of tRNA(leu(UUR)) nt3243A-->G mutation with the method of polymerase chain reaction (PCR) and restriction fragment length polymorphism. Cytochrome C oxidase activity was measured by the rate of cyanide-sensitive oxidation of reduced cytochrome C using luminosity photographer.

RESULTS

Cytochrome C oxidase activity was significantly lower in the PIH group than that of controls. The mitochondrial DNA mutation at position 3243 was not found in any of the cases.

CONCLUSION

These results suggested that the decreased activity of cytochrome C oxidase might impair the energy production, leading to the mitochondrial dysfunction and placental dysfunction in PIH patients. Mitochondrial dysfunction may be involved in the pathogenesis of preeclampsia. The particular mutation of mitochondrial DNA may not be the common contributor of PIH.