Hemoregulatorypeptide5b is a synthetic analog of granulocyte chalone which initially identified in extracts of rodent bone marrow and human leukocytes. Monomer inhibits both formations of GM-CFC colonies and cytotoxic drug-induced recruitment of murine
Small Cardioactive Peptide B (SCPB), a neurally active peptide, stimulates adenylate cyclase activity in particulate fractions of both heart and gill tissues with EC50s of 0.1 and 1.0 μM, respectively.