Verano-Braga T, Rocha-Resende C, Silva D M, Ianzer D, Martin-Eauclaire M F, Bougis P E, de Lima M E, Santos R A S, Pimenta A M C
Departamento de Bioquímica e Imunologia, ICB, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, 31270-901 Pampulha, Belo Horizonte, Brazil.
Biochem Biophys Res Commun. 2008 Jul 4;371(3):515-20. doi: 10.1016/j.bbrc.2008.04.104. Epub 2008 Apr 28.
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.
采用蛋白质组学方法，在黄蝎子锯齿钝尾蝎（Tityus serrulatus）的毒液中发现了一个新的肽结构家族。锯齿钝尾蝎降压肽（TsHpt）是无规卷曲的线性肽，具有类似缓激肽增强肽（BPP）的氨基酸特征。该家族的首个成员TsHpt-I（2.7 kDa）能够增强缓激肽（BK）对正常血压大鼠的降压作用。以该肽的C末端为模板，设计了一种合成类似物肽（TsHpt-I([17-25])）以保持BK增强作用。在天然和合成的TsHpt上均观察到了与BK无关的显著降压作用。为了更好地评估这种降压作用，我们检测了雄性Wistar大鼠主动脉环的血管舒张情况，这些肽能够诱导依赖于NO释放的内皮依赖性血管舒张。两种TsHpt均不能抑制ACE活性。这些肽似乎通过依赖于NO且不依赖于ACE的机制发挥其抗高血压作用。
