Evaluation of a Rat Model of Preeclampsia for HELLP Syndrome Characteristics

Abstract

Objective: To determine whether a rat model of preeclampsia includes features consistent with HELLP (hemolysis, elevated liver enzymes, low platelets) syndrome.

Methods: Preeclampsia was induced experimentally in timed-pregnant Sprague-Dawley rats using the reduced uterine perfusion pressure (RUPP) model. On day 14 of gestation, silver clips were placed around the aorta below the renal arteries and on the left and right uterine arcade at the ovarian artery. All animals were chronically instrumented to determine conscious blood pressure and to obtain blood samples for analysis of complete blood count, platelet count, liver function tests, uric acid, creatinine, and albumin. Blood samples were collected and animals sacrificed on day 19 of gestation, at which time placental and pup weight were obtained. A control group was analyzed similarly. Statistical analysis was performed with the Student t test.

Results: The RUPP model animals (n = 8), when compared with the normotensive controls (n = 9), did not show a statistically significant different in hemoglobin, platelets, liver function tests, uric acid, creatinine, or albumin, although the mean arterial pressure was higher (mean ± SD 131.9 ± 17.1 mmHg versus 104.0 ± 14.0 mmHg, respectively; P = 0.003) and pup number was lower (RUPP 6.6 ± 2.4 versus control 13.8 ± 2.3, P < .001).

Conclusion: Although decreased uteroplacental perfusion induces changes similar to symptoms of preeclampsia, the RUPP rat model does not appear to express features of HELLP syndrome.

Keywords

HELLP syndrome reduced uterine perfusion pressure rat model

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