Increased plasma adenosine concentrations and the severity of preeclampsia

OBJECTIVE: To investigate the relationship between changes in plasma adenosine and the severity of preeclampsia, and norepinephrine and tumor necrosis factor-alpha concentrations. METHODS: Plasma concentrations of adenosine, norepinephrine, and tumor necrosis factor-alpha relating to the pathogenesis of preeclampsia were measured in women with mild (n = 21) and severe (n = 21) preeclampsia and normal pregnancies (n = 21), matched for age, gestational age, and parity, in the third trimester of pregnancy. We then evaluated the relationships among plasma adenosine, norepinephrine, tumor necrosis factor-alpha concentrations, and the severity of preeclampsia. RESULTS: Mean plasma adenosine, norepinephrine, and tumor necrosis factor-alpha concentrations were significantly higher in women with mild and severe preeclampsia than in normal control subjects (P <.05). In women with preeclampsia, plasma adenosine concentrations increased according to the severity of preeclampsia (0.60 +/- 0.03 micromol/L and 0.72 +/- 0.03 micromol/L, respectively, versus 0.41 +/- 0.03 micromol/L for normal subjects), which correlated with increases of norepinephrine and tumor necrosis factor-alpha concentrations (r =.58, P <.05; r =.49, P <.05, respectively). In preeclampsia, norepinephrine concentration also correlated with maternal blood pressure (r =.50, P <.05). CONCLUSION: Adenosine is an established suppressor of the effects of norepinephrine and tumor necrosis factor-alpha. The increased plasma concentrations of adenosine in preeclampsia might serve to counteract further progression of the complication.