Angiotensin-II type 1 receptor (AT1R) and alpha-1D adrenoceptor form a heterodimer during pregnancy-induced hypertension.

Pregnancy courses with low response to angiotensin II and adrenergic agonists. In preeclampsia, both effects are reverted. It is known that angiotensin II regulates adrenergic system. It is not known, however, the interaction between both systems receptors. Our aim was to study if AT(1)R and alpha1D adrenoceptor heterodimerize in preeclampsia. We used subrenal aorctic coarctation in pregnant rats. Aortic tissues were prepared for confocal imaging and coimmunoprecipitated for alpha1D and AT(1) receptors. We found that AT(1)R and alpha1D adrenoceptor heterodimerize in both, healthy and preeclamptic groups. In healthy pregnant rats, heterodimer is barely detected. In preeclamptic rats however, we found higher heterodimerization. These results suggest that AT(1)R and alpha1D -adrenoceptor may form heterodimers, and may play a role in preeclampsia.