Inhibition of their Breakdown and Release of Endogenous Opioid Peptides from the Myenteric Plexus - Longitudinal Muscle of the Guinea - Pig Ileum Two different copies of Alexander T McKnight, Alistair D Corbett and Hans W Kosterlitz, 'Inhibition of their Breakdown and Release of Endogenous Opioid Peptides from the Myenteric Plexus - Longitudinal Muscle of the Guinea - Pig Ileum' reprinted from H Takagi and E J Simon, eds., 'Advances in Endogenous and Exogenous Opioids Proceedings of the International Narcotic Research Conference' (Tokyo, 1981), 188 - 190. 26 - 30 July 1981