K. Matsubara et al., SERUM PLATELET-ACTIVATING-FACTOR ACETYLHYDROLASE ACTIVITY IN NORMAL-PREGNANCY AND PREECLAMPSIA, Hypertension in pregnancy, 15(1), 1996, pp. 51-59
Objective: The aim of this study was to elucidate the roles of platele
t-activating factor acetylhydrolase (PAF-AH) in normal and hypertensiv
e pregnancies. Method: Changes in serum PAF-AH activity were investiga
ted in 13 nonpregnant women, 168 normal pregnant women, 11 women in no
rmal puerperium, and 35 pregnant women with preeclampsia (mild: 28, se
vere: 7). Serum PAF-AH activity was measured by the method of Staffori
ni et al. Results: The serum PAF-AH activity of normal pregnant women
between 5 and 34 weeks gestation was significantly lower than that of
nonpregnant women, increasing after 34 weeks gestation and returning t
o nonpregnant levels within 1 month after delivery. In the pregnant wo
men with mild preeclampsia at 28-41 weeks gestation, serum PAF-AH acti
vity (28.0 +/- 1.0 nmol/min/mL, mean +/- SEM, n = 28) was significantl
y (P < 0.01) higher than that in gestational-age-matched normal pregna
nt women (21.3 +/- 0.8 nmol/min/ml, n = 73). However, in the pregnant
women with severe preeclampsia, the activity (12.5 +/- 3.9 nmol/min/mL
, n = 7) was significantly lower (P < 0.01). Three of 7 severe preecla
mptic patients showed extraordinarily low PAF-AH activity even before
the onset of preeclampsia. Conclusion: We found remarkable differences
between the serum PAF-AH levels in mild and severe preeclampsia. In m
ild preeclampsia, the increased PAF-AH activity may play a role in reg
ulation of the local PAF concentration. On the other hand, some of the
women with severe preeclampsia showed extraordinarily low PAF-AH acti
vity, suggesting that such a regulatory mechanism of local PAF concent
ration may not operate in the patients.