“The contractile responses produced by thrombin, trypsin , SFLLRN‐NH2 and SLIGRL‐NH2 were markedly reduced in the presence of the cyclo‐oxygenase inhibitor, indomethacin , whilst the small contractile response produced by NRLLFS‐NH2 and LRGILS‐NH2 were insensitive to indomethacin.”