Effect of Glutathione on Blood Pressure, Postnatal Lung Growth and Neonatal Outcome In A Rat Model of Pre-Eclampsia

Background: Pre-eclampsia is a human pregnancy-specific disorder that adversely
affects the mother (by vascular dysfunction)and the fetus (by intrauterine growth
restriction). A large portion of the prenatal mortality is consequently due to
iatrogenic prematurity. Up to 15% of preterm births is a result of pre-eclampsia . The
combination of hypertension plus proteinuria markedly increases the risk of prenatal
morbidity and mortality over that of hypertension alone.Aim of the study:To
elucidate the effect of addition of glutathione on lipid peroxidation products, blood
pressure, proteinuria and neonatal outcome in a rat model of pre-eclampsia induced
by NG-nitro-L-arginine-methyl ester (L-NAME), an inhibitor of nitric oxide synthase.
Study Design: Adult pregnant rats (n =30) were allocated into three groups
according to medication they received on day 17 from gestation to term. Rats were
randomized into control group (n=10) and groups received L-NAME, 50 mg/day
orally. (pre-eclampetic group, n = 10) and L-NAME + glutathione, 60mg/kg i.p.
(treated group, n= 10) Blood levels of superoxide dismutase (SOD), catalase (CAT)
and malondialdehyde (MDA) were assessed .Mean systolic blood pressure (BP)
(measured with a tail – cuff device), levels of proteinuria,total urine output ,pups
birth weight and percentages of live and dead pups were recorded. Results: Mean
systolic BP, plasma levels of SOD, CAT and MDA of pregnant rats were higher in
pre-eclamptic group than in control group. Intreated group these plasma levels were
lower than in pre-eclamptic group but still higher than those of control group. A
positive correlation between systolic BPs on day 20 and SOD levels was recordedin
both pre-eclamptic and treated groups. Birth weights of pups were higher in the
control group than in the other groups. Pupsof treated group with glutathione had
better survival rates than those of control and pre-eclamptic groups. The mean total
body weight, lung weight, internal alveolar wall thickness and internal alveolar
surface area of pups of pre-eclamptic group were significantly higher than those of
control and treated groups. Histological changes: The lung specimens of pups of pre-eclamptic mothers showed irregular, collapsed, small alveoli. The lumnia of these
alveoli contained oedematous fluid rich in erythrocytes. The interalveolar speta were
relatively thickened and more cellular than control. The treated group showed more
or less the same morphological findings as the control group.Conclusion:In this rat
model of pre-eclampsia, hypertension, proteinuria, oxidative stress of pregnant rats, a
high neonatal death rate and pathological changes of lungs structure of pups, are
reversed by exogenous antioxidant use.