MODULATION OF EXCITATION TRANSMISSION IN THE INTRACARDIAC GANGLIONIC SYSTEM BY THE OPIOID PEPTIDE DERMORPHIN

It has recently been found that luteinizing hormone releasing hormone (LHRH), substance P, vasoactive intestinal polypeptide, and neurotensin modulate the transmission of excitation in the intracardiac ganglia [6, 8, i0]. This suggests that other regulatory peptides (RP) may act as modulators of intracardiac transmission: the most suitable candidates for this role are opioids, for their effect on excitation has been demonstrated in many autonomic ganglia [5].