Apelinerjik Sistemin Vasküler Fonksiyonel Etkileri

Abstract

The apelinergic system consists of apelin, elabela, and their common receptor apelin receptor (APJ). APJ is a G protein-coupled receptor. Apelin is the first discovered endogenous APJ ligand. Later, elabela was discovered and added to the system. Apelinergic system components have a widespread expression in the human body. The apelinergic system which plays a role in many physiological processes such as body-fluid homeostasis, energy metabolism, and regulation of cardiac contractility participates in the regulation of vascular tone and blood pressure. Apelin and elabela, which have similar effects on vascular tone, differ in their effect mechanisms. APJ is expressed in both vascular endothelial cells and vascular smooth muscle cells. This situation is important because it mediates the opposite effects in vascular tension. Apelin usually has a vasodilator effect through the activation of the endothelial nitric oxide synthase/nitric oxide (NO) pathway in physiological conditions. However, in the absence of a functional endothelium, apelin causes vasoconstriction. Elabela has a vasodilator effect similar to apelin, but it is thought that NO has no role in the vasodilator effect of elabela. When apelin and elabela are administered peripherally, they usually lower blood pressure and exhibit an antihypertensive effect. Therefore, the apelinergic system has great potential to develop alternative agents for the treatment of hypertensive diseases such as essential hypertension and pulmonary hypertension. The half-lives of apelin and elabela are quite short, and current studies have focused on developing longer-acting apelinergic analogs. In this review, we focused on the vascular functional effects and effect mechanisms of the apelinergic system.