title: Tityus serrulatus Hypotensins: a new family of peptides from scorpion venom.
abstract: Using a proteomic approach, a new structural family of peptides was put in evidence in the venom of the yellow scorpion Tityus serrulatus. Tityus serrulatus Hypotensins (TsHpt) are random-coiled linear peptides and have a similar bradykinin-potentiating peptide (BPP) amino acid signature. TsHpt-I (2.7kDa), the first member of this family, was able to potentiate the hypotensive effects of bradykinin (BK) in normotensive rats. Using the C-terminal of this peptide as a template, a synthetic analog peptide (TsHpt-I([17-25])) was designed to held the BK-potentiating effect. A relevant hypotensive effect, independent on BK, was also observed on both TsHpt (native and synthetic). To better evaluate this hypotensive effect, we examined the vasorelaxation of aortic rings from male Wistar rats and the peptides were able to induce endothelium-dependent vasorelaxation dependent on NO release. Both TsHpt could not inhibit ACE activity. These peptides appear to exert their anti-hypertensive effect through NO-dependent and ACE-independent mechanisms.
authors.affiliation: Departamento de Bioquímica e Imunologia, ICB, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, 31270-901 Pampulha, Belo Horizonte, Brazil.
authors.forename: T
authors.initials: T
authors.lastname: Verano-Braga
authors.forename: C
authors.initials: C
authors.lastname: Rocha-Resende
authors.forename: D M
authors.initials: DM
authors.lastname: Silva
authors.forename: D
authors.initials: D
authors.lastname: Ianzer
authors.forename: M F
authors.initials: MF
authors.lastname: Martin-Eauclaire
authors.forename: P E
authors.initials: PE
authors.lastname: Bougis
authors.forename: M E
authors.initials: ME
authors.lastname: de Lima
authors.forename: R A S
authors.initials: RA
authors.lastname: Santos
authors.forename: A M C
authors.initials: AM
authors.lastname: Pimenta
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000959:Antihypertensive Agents / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D001920:Bradykinin / Q000494:pharmacology; D004357:Drug Synergism; D008297:Male; D008969:Molecular Sequence Data; D009569:Nitric Oxide / Q000378:metabolism; D010455:Peptides / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D007703:Peptidyl-Dipeptidase A / Q000187:drug effects; D051381:Rats; D017208:Rats, Wistar; D012604:Scorpion Venoms / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D014664:Vasodilation; D014665:Vasodilator Agents / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*
chemical_list: D000959:Antihypertensive Agents; D010455:Peptides; D012604:Scorpion Venoms; D014665:Vasodilator Agents; D009569:Nitric Oxide; D007703:Peptidyl-Dipeptidase A; D001920:Bradykinin