Abstract
Preeclampsia (PE) is a hypertensive disorder of pregnancy described as a condition of excessive sympathoexcitation. PE places a woman at increased risk for lifelong hypertension and cognitive impairment. Cerebral blood velocity is blunted in response to a vasoactive stimulus in women with a history of PE. This study investigated how a sympathoexcitatory stimulus affects cerebral blood velocity in women with a history of PE. Middle cerebral artery blood velocity (MCAv) and beat-to-beat mean arterial blood pressure (MAP) were measured in postmenopausal women with a history of PE (n = 21; age = 59 +/- 5 yr) and a history of a normotensive pregnancy (NP; n = 27; age = 58 +/- 4 yr), at baseline, during isometric handgrip to fatigue (IHG) followed by postexercise ischemia (PEI), and a recovery period (REC). Baseline MAP and MAP responses to IIIG and PEI did not differ between groups. MCAv at baseline and throughout the stimulus was lower in PE women compared with NP women (P < 0.05 for all). MCAv increased during IHG in both groups (P < 0.05). This increase in MCAv was greater in PE compared with NP women during IHG and REC (IHG: PE 13 +/- 2% vs. NP 9 +/- 2%; REC: PE 3 +/- 2% vs. NP -2 +/- 2%; P < 0.05 for both). Thus, a history of PE is associated with low baseline cerebral blood velocity but an augmented response to a sympathoexcitatory stimulus. These changes in cerebral blood flow regulation may lead to an increased risk for cognitive impairment in women with a history of PE.