CARDIOVASCULAR JOURNAL OF AFRICA • Vol 23, No 3, April 2012
158
AFRICA
factors such as race have an influence on the incidence of PE in
a population.
54
The high incidence of PE in South Africa as well
as the increased risk of mortality associated with PE in black
women stress the need for research on homogenous population
groups.
We recommend that future research should also incorporate the
investigation of the heterodimerisation of theAT1 and bradykinin
B2
receptors in black South African women. Furthermore, the
interplay between the angiogenic/anti-angiogenic pathway, RAS
and other theories, such as that of oxidative stress and the role of
the inflammatory system in PE, should be explored.
Two of the limitations of this study were the small sample
size that affected the statistical analysis, and the fact we did not
measure serum levels of angiotensin II and AT1 autoantibodies.
Conclusion
The findings of this study lead us to conclude that the aetiology
and pathogenesis of early- and late-onset PE are, to some
extent different, especially in our population sample. Our data
demonstrate that while a predominance of an anti-angiogenic
state may be an important role player in both early- and late-
onset PE, in the latter, AT1 receptor up-regulation and the RAS
could also play a role.
We are grateful to the South African Medical Research Council for financial
assistance and the Africa Centre, University of KwaZulu-Natal, for allowing
us the use of their laboratories for ELISA studies.
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