ISOLATION, CHARACTERIZATION AND BIOLOGICAL PROPERTIES OF 2 KININ-LIKEPEPTIDES (PEPTIDE-S AND PEPTIDE-R) FROM SCAPTOCOSA-RAPTORIA VENOM

Two peptides with kinin-like biological properties were isolated by ch romatography on a Sephadex G-10 column followed by high-performance li quid chromatography, from the venom of the spider Scaptocosa raptoria. The isolated peptides (peptide-S and peptide-R) were shown to cause c ontraction on the isolated guinea-pig ileum at amounts equivalent to t hose shown by bradykinin. Both peptides relaxed the isolated rat duode num, increased the capillary permeability, caused decreasing and bipha sic effect of the arterial blood pressure in conscious rats and induce d oedema in the rat paw. The peptides had activity and structural simi larities to other peptides (kinin-like) isolated from venoms. The comp lete amino acid analysis gave peptide-S a structure with 36 amino acid residues and peptide-R 22 amino acid residues. The mol. wts were esti mated to be in the range of 4000 and 2870, respectively. (C) 1998 Else vier Science Ltd. All rights reserved.