Highlights on endothelins: a review

The physiological and pathological roles of endothelins remain incompletely understood. While their vasoconstrictive effects are well-documented, their dual actions as vasodilators under normal conditions create uncertainty. Prior research has shown that endothelins influence vascular tone through receptor interactions, but the mechanisms underlying their dual behavior are not fully resolved. This gap motivated investigations into how endothelin-1 interacts with different receptors in various contexts. No prior work had resolved the transition from vasodilation to vasoconstriction in disease states. Understanding these dynamics is essential for developing targeted therapies. The role of endothelin converting enzymes in ET-1 synthesis remains a key focus. Researchers continue to explore how endothelin signaling shifts in pathological conditions.

This review aims to clarify the dual physiological and pathological roles of endothelin-1. The specific problem is understanding how ET-1 can act as both a vasodilator and vasoconstrictor depending on context. The motivation stems from the need to identify therapeutic targets for conditions like hypertension and heart failure. The authors propose that receptor-specific activation explains this duality. They suggest that ETB1 receptors mediate vasodilation while ETA and ETB2 receptors mediate vasoconstriction. This distinction is critical for drug development. The review also highlights the importance of endothelin converting enzymes in ET-1 production. These insights could guide future therapeutic strategies.

The authors conducted a literature review focusing on endothelin-1's physiological and pathological roles. They analyzed receptor activation patterns in different tissues. The review approach included examining experimental and clinical evidence. They compared ET-1's actions in healthy and diseased states. The synthesis of endothelin peptides from precursor proteins was a key focus. Receptor subtypes ETA, ETB1, and ETB2 were evaluated for their distinct functions. The review also considered the role of endothelin converting enzymes in ET-1 secretion. The authors synthesized findings from multiple studies to propose a comprehensive model.

ET-1 acts as a vasodilator through ETB1 receptors in physiological conditions. It stimulates nitric oxide and prostacyclin release from endothelial cells. In pathological states, ET-1 binds to ETA and ETB2 receptors, causing vasoconstriction. This shift is observed in hypertension and heart failure. The dual action of ET-1 is receptor-specific and context-dependent. Endothelin converting enzymes are critical for ET-1 synthesis. The basolateral secretion of ET-1 from endothelial cells is well-established. These findings suggest that receptor activation patterns determine ET-1's effects.

The authors propose that ET-1's effects depend on receptor activation patterns. They suggest that ETB1 receptors mediate vasodilation while ETA and ETB2 mediate vasoconstriction. The synthesis and secretion of ET-1 involve endothelin converting enzymes. The dual physiological and pathological roles of ET-1 are receptor-specific. The authors propose that drugs targeting these receptors could be beneficial in disease states. They suggest that ET-1's vasoconstrictive effects are prominent in hypertension and heart failure. The review supports the development of ET antagonists for cardiovascular therapy. These findings could guide future research on endothelin-based treatments.