Pregnancy Induced Reprogramming of Endothelial Function in Response to ATP: Evidence for Post Receptor Ca Signaling Plasticity - Extracellular ATP and Adenosine as Regulators of Endothelial Cell Function - page 205

like that observed in NP-UAEC and those with healthy pregnancy show responses
like that in P-UAEC. It is also noteworthy that in 'normal' HUVEC at least, P2Y2
receptor protein is expressed [10] and functionally coupled to [Ca 2+ ]i signaling
[10, 31], PLC beta 3 is present [2], and both TRPC3 [13] and CX43 [33] protein
expression have been reported in HUVEC preparations. Thus all the components
present in UAEC, whose interaction is adapted during pregnancy to achieve maxi-
mal [Ca 2+ ]i sensitive eNOS activation, are also present in HUVEC. The translation
of the studies described above on UAEC into the HUVEC culture model, as well as
the parallel imaging of [Ca 2+ ]i and NO in single cells still attached to the luminal
surface of freshly isolated vessels from normal and preeclamptic pregnancies could
yield invaluable insight into the mechanistic failures associated with this disease,
and a useful model to subsequently test treatments that could restore more normal
function.
Acknowledgments IMB would like to dedicate this review to all those who worked so dili-
gently on the many studies quoted herein over the past 15 years. The authors would also like
to acknowledge the support of NIH grants HL64601 and HL079020 dedicated to these Ca 2+ imag-
ing studies, and to NIH Program Project award HD 38843 for complimentary studies of UAEC
function. DB is the recipient of T32 award HD41921 for his part in this work towards a PhD in
the Endocrinology and Reproductive Physiology Graduate Training Program, at the University of
Wisconsin, Madison.
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