A synthetic peptide from Helix aspersa raises arterial pressure in rats

: New FMRF-amide like peptide, pGlu-Asp-Pro-Phe-Leu-Arg-Phe-NH2, originally isolated from the ganglia of Helix aspersa, was synthetized. Intravenous injections of this peptide (40-300 micrograms/kg) produce rapid dose dependent increase in the blood pressure and heart rate of anaesthetised rats. Since alpha-adrenoreceptor blockade with prazosin eliminated pressor response, it is concluded that the increase in the arterial pressure is mediated by sympathetic activation.