Difference in the response to angiotensin II between left and right ventricular endocardial endothelial cells

Abstract

Previous studies focused on the right ventricular endocardial endothelial cells (EECRs) and showed that angiotensin II (Ang II) induced increase in cytosolic and nuclear calcium via AT receptor activation. In the present study, we verified whether the response of left EECs (EECLs) to Ang II is different than that of EECRs. Our results showed that the EC of the Ang II-induced increase of cytosolic and nuclear calcium in EECLs was 10× higher (around 2 × 10 mol/L) than in EECRs (around 8 × 10 mol/L). The densities of both AT and AT receptors were also higher in EECLs than those previously reported in EECRs. The effect of Ang II was mediated in both cell types via the activation of AT receptors. Treatment with Ang II induced a significant increase of cytosolic and nuclear AT receptors in EECRs, whereas the opposite was found in EECLs. In both cell types, there was a transient increase of cytosolic and nuclear AT receptors following the Ang II treatment. In conclusion, our results showed that both AT and AT receptors densities are higher in both EECLs compared to what was reported in EECRs. The higher density of AT receptors in EECLs compared to REECs may explain, in part, the higher sensitivity of EECLs to Ang II.

High Na+ Salt Diet and Remodeling of Vascular Smooth Muscle and Endothelial Cells

“…Atef and Anand-Srivastava, including other authors, have demonstrated that the Gqα protein-related signaling pathway is a classical pathway of the hypertrophic response of VSMCs [ 33 , 34 ]. Generally, this pathway can be triggered by growth factors, or by one or more varieties of vasoactive substances, including angiotensin II, endothelin-1and neuropeptide Y [ 19 , 21 , 32 , 35 ].…”

Angiotensin II induces apoptosis of human right and left ventricular endocardial endothelial cells by activating the AT2receptor

“…The same group proposed that the balance of AT 1 /AT 2 receptor ratio is critical in the antagonistic actions between the two receptors (Miura et al 2010). Hence, the difference in the receptor type involved in Ang II-induced apoptosis between EECRs and EECLs in our study could be due to the difference in the ratio of AT 1 /AT 2 receptors at the plasma membrane level in these two cell types (Jacques et al 2017b).…”

“…Among these differences, our group has shown that the distribution of Ang II and its receptors, AT 1 and AT 2 , is different between EECRs and EECLs (Jacques et al 2003a(Jacques et al , 2017b. Also, EECLs are more sensitive to Ang II stimulation than EECRs (Jacques et al 2017b).…”

“…Furthermore, endocardial endothelial cells themselves are capable of secreting cardioactive factors such as NO (Andries et al 1998;SHAH, 1996), Ang II (Paul and Ganten, 1992), ET-1 (Mebazaa et al 1993;Abdel-Samad et al 2012, 2016 and NPY (Jacques et al 2003b). Studies from our laboratory (Jacques et al 2000a(Jacques et al , 2003b(Jacques et al , 2005(Jacques et al , 2006a(Jacques et al , s006b, 2017a(Jacques et al , 2017bJacques and Abdel-Samad, 2007;Abdel-Samad et al 2012, 2016Jules et al 2015), as well as from the literature (Brutsaert, 2003;Nosaka et al 1997;Ekman et al 1997;Kim et al 1999;Discigil et al 2009) showed differences between endocardial endothelial cells (EECs) isolated from the right and left ventricles (EECRs and EECLs respectively). Among these differences, our group has shown that the distribution of Ang II and its receptors, AT 1 and AT 2 , is different between EECRs and EECLs (Jacques et al 2003a(Jacques et al , 2017b.…”

“…Studies from our laboratory (Jacques et al 2000a(Jacques et al , 2003b(Jacques et al , 2005(Jacques et al , 2006a(Jacques et al , s006b, 2017a(Jacques et al , 2017bJacques and Abdel-Samad, 2007;Abdel-Samad et al 2012, 2016Jules et al 2015), as well as from the literature (Brutsaert, 2003;Nosaka et al 1997;Ekman et al 1997;Kim et al 1999;Discigil et al 2009) showed differences between endocardial endothelial cells (EECs) isolated from the right and left ventricles (EECRs and EECLs respectively). Among these differences, our group has shown that the distribution of Ang II and its receptors, AT 1 and AT 2 , is different between EECRs and EECLs (Jacques et al 2003a(Jacques et al , 2017b. Also, EECLs are more sensitive to Ang II stimulation than EECRs (Jacques et al 2017b).…”