Endothelin-1 is an amino acid peptide that is made in the cells lining the human vascular system. The compound binds to receptors within muscle tissue in the heart and causes it to contract. Aside from the regulation of heart contractions, it also controls heart rate. Endothelin-1 regulates vascular tone in the lungs in addition to the tone of the airways, keeping all pathways open and fully functional. Renal homeostasis is also managed because the substance has control over water and sodium excretion in the kidneys.
The endothelin system in the brain provides regulation of both cardiorespiratory functions and hormone release. Endothelin-1 also has a strong influence on the development of hypertension and heart failure. It causes the release of calcium in the heart, which has been linked to many health maladies.
When it is released, the effects of endothelin-1 take hold when the peptide binds to specific receptors. Binding to one type of receptor causes the production of a substance, which causes calcium to be released. Normal calcium stimulation triggers the contraction of smooth muscles in the heart as well as in the blood vessels.
Endothelin-1, as well as its genetic and peptide sequences, was not discovered until the late 1980s. The systems which it operates on have been studied since the 1950s, when it was realized some mechanism was responsible for controlling the movement of the heart and circulatory system. Upon its discovery, the substance was named for the endothelial cells within blood vessels, which it originates from.
In cases of heart failure, endothelin-1 is released by damaged vascular tissue and can be detrimental to heart function. It does this by causing an excessive release of calcium and by stimulating vascular muscle so that it enlarges. Inhibiting its uptake has been found to alleviate the symptoms of heart failure and in effect allows people to live longer. Compounds called receptor antagonists are used for this purpose. Specific ones target certain conditions, such as heart failure as well as pulmonary hypertension.
Endothelin-1 also influences general cell growth, embryonic development, neurological functions, such as those involved in pain signaling, and cancer cell growth. Endocrine function and various functions of the lungs and reproductive system are impacted by it as well. Endothelin-1 is essential for the body to function normally, but irregular amounts can have drastic effects that can lead to many different conditions and diseases.