(Pro)renin/renin receptor expression during normal and preeclamptic pregnancy in rats

Pregnancy is a physiological stage with profound cardiovascular changes leading to hypotension. Preeclampsia (PE) reverts these normal changes inducing hypertension. Renin-angiotensin system (RAS) has been related in PE genesis. It has been reported a novel receptor in the system, the Prorenin/Renin receptor (PRR), with several roles in renal and cardiovascular illnesses. It is not known, however, if PRR changes its expression or is activated during normal or PE-complicated pregnancy on tissues intimately related to hypertension. So, the aim of this work was to describe PRR expression during normal and hypertensive pregnancy in rats.

We used a subrenal aortic coarctation (SRAC) model in rats. Atria, septum and ventricular heart tissue, aorta and renal tissue samples were homogenized and immunoblotted using anti-PRR and anti-PLZF antibodies. We also measured gene expression by RT-PCR.

Hypertension and proteinuria were observed in SRAC-pregnant rats. In pregnant, non-SRAC rats, PRR showed a higher expression of both, gene and protein compared to non-pregnant rats in heart, aorta and kidney tissues. PE induces a very high expression of PRR in cardiac tissues and, on the contrary, decreases PRR expression in both, aorta and kidney. PLZF, a marker of PRR function, was augmented only in aorta and kidney in non-SRAC pregnant rats. In SRAC-pregnant rats, PLZF increment disappeared.

These findings indicate that PRR expression changes differently during pregnancy and PE in tissues related to cardiovascular functions and suggest a probable participation of the receptor during normal and preeclamptic pregnancy in the rat.