A family of peptides acting locally as autacoid or paracrine hormones. Three isoforms of the 21 amino acid peptide have been identified: ET-1, ET-2 andET-3. They are produced by a variety of cells, including endothelial and epithelial cells, macrophages and fibroblasts. Endothelins are characterised by two intra-chain disulphide rings, leading to a hairpin loop configuration, along with six conserved amino acid residues at the C terminus.

Endothelins are synthesised by the proteolysis of large pre-proendothelins, e which are cleaved to big endothelins, and then processed to the mature peptide by endothelin-converting enzyme. s

Endothelins induce dose-dependent contraction in vascular smooth muscle, S'

ET-1 being the most potent known endogenous vasoconstrictor. Two high affinity g endothelin receptors have been recognised, ETA and ETB. They have been |

characterised as seven transmembrane domain G-protein receptors coupled to h.

phospholipase C. The ETA receptor is the predominant type of receptor. g

Was this article helpful?

0 0
Tips and Tricks For Boosting Your Metabolism

Tips and Tricks For Boosting Your Metabolism

So maybe instead of being a pencil-neck dweeb, youre a bit of a fatty. Well, thats no problem either. Because this bonus will show you exactly how to burn that fat off AS you put on muscle. By boosting your metabolism and working out the way you normally do, you will get rid of all that chub and gain the hard, rippled muscles youve been dreaming of.

Get My Free Ebook

Post a comment