Affiliation:
1. Branch of Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry RAS
2. Pushchino State Natural-Science Institute
3. Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, RAS
Abstract
Previously, it was shown that the non-conventional toxin WTX from the venom of the cobra Naja kaouthia, when administered intravenously, caused a decrease in blood pressure (BP) and an increase in heart rate (HR) in rats (Ogay et al., 2005). To identify the site of the toxin molecule responsible for these effects, we studied the influence of synthetic peptide fragments of the WTX on BP and HR in normotensive male Sprague Dawley rats under general anesthesia induced by Telazol and Xylazine. It was found that peptides corresponding to the WTX central polypeptide loop, stabilized by a disulfide bond, at intravenous injection at concentrations from 0.1 to 1.0 mg/ml caused a dose-dependent decrease in BP, the HR increasing only in the first 5–10 minutes after administration. Thus, WTX fragments corresponding to the central polypeptide loop reproduce the decrease in blood pressure caused by the toxin.
Publisher
The Russian Academy of Sciences