Effects of selective reduced uterine perfusion pressure in pregnant rats.

Introduction: To assess the effects of selective reduced uterine perfusion pressure (SRUPP) in pregnant rats.

Methods: 20 pregnant Sprague-Dawley rats were allocated either to an intervention group, exposed to SRUPP (n = 10) or a control group, exposed to sham surgery (n = 10). Such procedures were performed on gestational day (GD) 14. The Mean arterial pressure (MAP) was measured on GD14 (before surgery) and GD20. We measured 18 h proteinuria on GD20. On GD21, mean fetal (MFW) and placental (MPW) weights were obtained. Oxidative stress and angiogenic markers were measured in placental tissue and urine. Mann Whitney U or Independent samples T test were used when appropriate. A two-sided P < 0.05 indicated statistical significance.

Results: MAP on GD20 was higher in the intervention group (109 ± 1.7 mmHg) when compared with the control group (83 ± 1.5 mmHg) (P = 0.002). There was no significant difference in urinary protein excretion (117 ± 3.1 mg/24 h versus 136 mg ± 2.8/24 h, P = 0.18), MFW (4.14 ± 0.05 versus 4.39 ± 0.04 g, P = 0.19) or MPW (0.43 ± 0.008 versus 0.44 ± 0.006 g, P = 0.73) between the intervention and the control groups, respectively. The oxidative stress was increased; whereas, the sFLT1 expression was not increased when the SRUPP group was compared with controls.

Discussion: SRUPP is associated with an increase in maternal MAP and oxidative stress and therefore it may become a useful tool in the study of pregnancy-related hypertensive disorders.