PART I. The Nature and Localization of Neuroseoretory Substances Isolation and Identification of Cardio-Excitor Hormone from the Pericardial Organs of<i>Cancer borealis</i>

Abstract

Extracts of the neurohemal pericardial organs from Cancer borealis have a cardio-excitor activity when tested on the isolated, perfused heart. Analysis of the extract indicates that there are two active peptides, similar in size and amino acid composition. The procedure for isolation of these peptides is presented, as well as a discussion of the proposed role of indolic substances as cardio-excitor agents.