Plasma adenosine levels and P-selectin expression on platelets in preeclampsia.
OBJECTIVE
To measure the correlation of plasma adenosine levels with platelet activation in women with preeclampsia.


METHODS
Plasma adenosine concentration and expression of P-selectin, a marker for platelet activation, were measured in 18 normal pregnant women and 18 preeclamptic women. The effect of 8-sulfophenyltheophylline, an adenosine receptor blocker, on expression of P-selectin on platelets also was measured.


RESULTS
Plasma adenosine level averaged 0.77 +/- 0.11 microM (standard error of the mean [SEM]) in women with preeclampsia, significantly higher than the mean level of 0.47 +/- 0.08 microM in women with normal pregnancies (P <.05). Expression of P-selectin on platelets averaged 7.8 +/- 1.2% in women with preeclampsia, also significantly higher than the mean level of 4.7 +/- 0.7% in normal pregnancy (P <.05). Adenosine receptor blockade significantly increased expression of P-selectin on platelets in women with preeclampsia by 26% (P <.05), which was significantly higher than the 13% increase of activation in those with normal pregnancies (P <.05).


CONCLUSIONS
Adenosine is an established platelet activation suppressor. Increased plasma levels of adenosine in preeclampsia might partially compensate and tend to prevent further excessive platelet activation in women with preeclampsia.
Department of Obstetrics and Gynecology, Nippon Medical School, Tokyo, Japan. yoshi-l@nms.ac.jp
Y
Y
Yoneyama
S
S
Suzuki
R
R
Sawa
Y
Y
Kiyokawa
G G
GG
Power
T
T
Araki
D000241:Adenosine / Q000037:antagonists & inhibitors / Q000097:blood*; D000328:Adult; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D019007:P-Selectin / Q000097:blood* / Q000187:drug effects; D015539:Platelet Activation / Q000502:physiology; D011225:Pre-Eclampsia / Q000097:blood*; D011247:Pregnancy; D013806:Theophylline / Q000031:analogs & derivatives* / Q000494:pharmacology
D019007:P-Selectin; C031433:8-(4-sulfophenyl)theophylline; D013806:Theophylline; D000241:Adenosine