Acute systemic inhibition of inflammation augments endothelium-dependent dilation in women with a history of preeclamptic pregnancy.

Abstract

Women who have had preeclampsia demonstrate microvascular endothelial-dysfunction, mediated in part by reduced nitric oxide (NO)-dependent dilation. Preeclamptic pregnancies are associated with elevated inflammation, and inhibition of inflammation attenuates endothelial damage in animal models of preeclampsia. However, it is unclear if inhibition of vascular inflammation improves endothelial function in women after a preeclamptic pregnancy. Using the cutaneous microcirculation as a model, we hypothesized that acute systemic inhibition of vascular inflammation (oral salsalate; 1500mg/twice daily, 4days) would improve endothelium- and NO-dependent vasodilation in women with a history of preeclampsia (PE) but not in women with a history of uncomplicated pregnancy (HC). Twelve HC (30±1yrs, 10±2months postpartum) and 10 PE (30±2yrs, 8±2months postpartum) participated in a double-blind placebo-controlled study. Following each treatment, 2 intradermal microdialysis fibers were placed in the skin of the ventral forearm for graded infusion of acetylcholine (Ach, 10-7-102mM) or Ach+15mM L-NAME (NO synthase antagonist). Red blood cell flux was measured over each site by laser-Doppler flowmetry (LDF). Cutaneous vascular conductance was calculated (CVC=LDF/mean arterial pressure) and normalized to maximum (%CVCmax; 28mM SNP+local heat 43°C). ACh-induced (77±3 vs. 92±3%CVCmax; p=0.01) and NO-dependent (20±6 vs. 33±4%; p=0.02) vasodilation were attenuated in PE compared to HC. Salsalate augmented ACh-induced (95±2%CVCmax; p=0.002) and NO-dependent (39±3%; p=0.009) dilation in PE compared to placebo but had no effect in HC (all p>0.05). Salsalate treatment augmented endothelium-dependent vasodilation via NO-mediated pathways in women who have had preeclampsia, suggesting that inflammatory signaling mediates persistent endothelial dysfunction following preeclampsia.