[36-OR]: Treatment with Vitamin D attenuates blood pressure and immune activation in a preeclamptic rat model.

Objectives Vitamin D deficiency is associated with increased prevalence of hypertension and chronic inflammatory diseases both in the presence and absence of pregnancy. Preeclampsia (PE) is characterized by late-onset hypertension in pregnancy is also associated with increased CD4+ T cells, agonistic autoantibodies to the angiotensin type II receptor (AT1-AA) and decreases in T regulatory cells (TREGs). We tested the hypothesis that Vitamin D2 and D3 treatment would ameliorate hypertension and or other hallmarks of PE in the RUPP rat. Methods We utilized the Reduced Uterine Perfusion Pressure (RUPP) model of PE which exhibits hypertension (MAP), increased CD4+ T cells, AT1-AA and reduced TREGs. RUPP surgery was performed on gestation day 14 (GD14) with 50 μM VD2 or VD3 oral administration on GD14-18. Rats were sacrificed on GD19 with MAP measured by indwelling carotid catheter. Results MAP in RUPP rats was 122 ± 2.3 compared to 104.2 ± 2.4 mmHg in NP rats ( n = 12–18, p < 0.05). Supplementation with either VD2 or VD3 lowered MAP to 117.6 ± 3.9 or 114.3 ± 2.9 mmHg, respectively ( n = 9–12). CD4+ T cells increased from 2.8 ± 1.0% in NP to 8.5 ± 1.5% in RUPP ( n = 8–11, p < 0.05) which decreased to 1.2 ± 0.4% with VD2 and to 4.6 ± 3.7% with VD3 ( n = 2–3). AT1-AA, measured via chronotropic response in cardiomyocytes, were 19.5 ± 0.4 beats/min in RUPP rats and decreased to 15.4 ± 0.7 with VD3, and further to 8.3 ± 0.5 with VD2 ( n = 5, p < 0.05). Circulating B cells increased in RUPP rats compared to NP (9.0 ± 3.7% to 5.5 ± 2.3%, n = 5–10) while VD2 had no effect (11.6 ± 3.0%, n = 6) but VD3 treatment decreased B cells in RUPP rats (6.8 ± 3.3%, n = 7). Conclusions Taken together, these data indicate that Vitamin D supplementation reduced MAP and inflammation in a rat model of PE, thereby suggesting a role for Vitamin D as an agent to reduce the pathophysiology associated with PE. Disclosures J.L. Faulkner: None. M.M. Darby: None. D.C. Cornelius: None. A.C. Harmon: None. L.M. Amaral: None. J. Moseley: None. F. Herse: None. G. Wallukat: None. R. Dechend: None. B. LaMarca: None. [ABSTRACT FROM AUTHOR]