The roles of angiotensin-converting enzyme 2 inhibitor, melatonin and its agonist on angiotensin II reactivity in intact and denuded rat aortic rings

Abstract

Background

The pineal product melatonin (MEL) modulates blood vessels through G protein-coupled receptors (GPCRs) called melatonin type 1 receptor (MT₁R) and melatonin type 2 receptor (MT₂R), in that order. The renin-angiotensin system (RAS), which breaks down angiotensin II (Ang II) to create Ang 1–7, is thought to be mostly controlled by angiotensin-converting enzyme-2 (ACE₂).

Aim

The current work examines the involvement of ACE₂ inhibitor, MEL, and ramelteon (RAM) in the vascular response to Ang II activities in the endothelial denuded (E-) and intact (E+) rat isolated thoracic aortic rings.

Method

The isometric tension was measured to evaluate the vascular Ang II contractility using dose response curve (DRC).

Results

MEL and RAM caused a rightward shift of Ang II in endothelium E + and endothelium E- aorta.

Conclusion

According to the current study, the distribution of MEL receptors and the endothelium’s condition are related to the vasomodulatory effect of MEL and ACE₂ on Ang II attenuation. These physiological interactions can control vascular tone and increase Ang II reactivity denude endothelial layaer.

Keywords:

• Melatonin
• ramelteon
• ACE₂ inhibitor
• ang II

Acknowledgement

The authors acknowledge the financial support of the work by Mohammed Saadi Ahmed the Chairman of Erbil Bank, Iraq for investment and finance.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Ethical approval

This study complies with the Declaration of the ARRIVE guidelines and was performed according to ethics committee approval.

Additional information

Funding

The author(s) reported there is no funding associated with the work featured in this article.