ENDOTHELIN-1 (ET-1), the principal peptide of the endothelin family, has been shown to have a variety of biological activities in both vascular and nonvascular tissues, including the heart, the kidney, and the central nervous system.
At the cellular level, the effects of ET-1 appear to be mediated by two specific receptor subtypes termed ETA and ETB, both of which are functionally coupled to phospholipase C (PLC).
The C-terminal fragment , which is a highly conserved sequence in the peptides of the ET family, has been shown to discriminate between the two ET receptor subtypes termed ETA and ETB since it activates only the latter ones.
References:
1. Rubanyi, G. M., and M. A. Polokoff. Endothelins: molecular biology, biochemistry, pharmacology, physiology, and pathophysiology. Pharmacol. Rev. 46: 325–415, 1994
2. Simonson MS. Endothelins: multifunctional renal peptides. Physiol Rev 1993; 73: 375–411.
3. PM Vanhoutte Endothelin-1. A matter of life and breath, Nature, 368 (1994), pp. 693–694