Opioid receptors in cardiovascular function.

Opioid receptors are G protein-coupled receptors expressed by various cells in the heart, including myocytes and nerve fibres, and play a crucial role in modulating cardiac function. These receptors influence neural transmission, heart rate and myocyte contractility, offering cardioprotection. Our review provides a comprehensive examination of opioid receptor functions across multiple cardiovascular cell types, including cardiomyocytes, endothelial cells and smooth muscle cells, encompassing excitation-contraction coupling and vascular tone regulation. Additionally, we address the crosstalk between opioid receptors and other systems, such as the β-adrenoceptor system and the renin-angiotensin system. This integrated approach enables a more complete understanding of how opioid systems influence overall cardiovascular homeostasis, presenting significant advances in the field. Understanding the role of these receptors could help in developing novel treatments for various cardiovascular conditions. In conclusion, this review discusses the importance of opioid receptors and their signalling pathways in mediating cardiovascular functions, highlighting their potential as therapeutic targets for cardiovascular diseases.