Using the Reduced Uterine Perfusion Pressure model of preeclampsia to study the blood brain barrier permeability

Abstract

***Using the Reduced Uterine Perfusion Pressure model of preeclampsia to study the blood brain barrier permeability***AIMS: To use the Reduced Uterine Perfusion Pressure (RUPP) model for preeclampsia to describe and evaluate the blood brain barrier permeability in pregnant rats.METHODS: Forty-one pregnant Wistar rats were divided into different intervention groups between 13 to 15 days of gestation: Pregnant-Control (PC; n=12), Reduced Uterine Perfusion Pressure (RUPP; n=15), Invasive Blood Pressure-Control (IBP; n=7) and Reduced Uterine Perfusion Pressure and Invasive Blood Pressure (RUPP-IBP; n=7). The 14 rats of groups IBP and RUPP-IBP had their mean arterial pressure measured at day 21. All animals were then sacrificed, administered Evans Blue dye through the tail vein and perfused with paraformaldehyde 4%. Brains were removed and evaluated by a blinded pathologist. Results are presented as means and standard errors. Comparisons between the groups were performed using Student's t-test for continuous variables and Fisher’s exact test for categorical variables. Statistical significance was set as a p value less than 0.05.RESULTS: Mean arterial pressure averaged 85.4±2.2 mmHg in the IPB group and 102.5±8.3 mmHg in the RUPP-IPB group (p=0.002). Among all the RUPP rats (RUPP and RUPP-IBP groups), 82% had a positive staining with Evans Blue dye for at least one of the brain hemispheres, while none of the pregnant control rats (PC and IBP groups) had brain staining (p<0.001).CONCLUSIONS: In this study, altered permeability of the blood brain barrier was successfully reproduced in pregnant rats exposed to the RUPP protocol. Therefore, we concluded that the RUPP model is a valid surrogate to study blood brain barrier abnormalities.