Objective:

To determine whether preeclampsia enhances superoxide generation of neutrophils.

Methods:

Samples were obtained from 12 normal nonpregnant, 15 normal pregnant, and 11 preeclamptic women. The superoxide production of neutrophils was measured by the superoxide dismutase-inhibitable reduction of ferricy-tochrome C at 550-540 nm using a dual-wavelength spectrophotometer.

Results:

N-formyl-methionyl-leucyl-phenylalanine (FMLP)-induced superoxide production of neutrophils was significantly higher in preeclamptics than in normal nonpregnant and pregnant subjects, whereas phorbol 12-myristate 13-acetate-induced superoxide production did not differ among them. When neutrophils prepared from normal nonpregnant women were preincubated with sera from the study groups, sera from preeclamptics enhanced the FMLP-induced superoxide production to about twice that of the other subjects. The serum-enhancing factor appeared to be a heat-labile protein, different from other known activators.

Conclusion:

Preeclampsia is characterized by the presence of a neutrophil activator that enhances superoxide production. This enhanced production may contribute to the pathophysiologic changes observed in preeclampsia.