Effects of taftsin-pro-gly-pro peptide on heart rate variability indices in rats in different motor activities

Background: The cardiotropic effects of a synthetic peptide with the anxiolytic activity of taftsinPro-Gly-Pro (taftsin-PGP) under stress was investigated. Previously, the effect of this peptide on the state of the cardiovascular system, which plays an important role in the adaptive reactions of the body under stress, has not been studied. The aim of the study: To study the effect of the regulatory peptide taftsin-Pro-Gly-Pro on the heart rate variability (HRV) indices of rats under conditions of various motor activity. Materials and methods: The study was performed on 48 Wistar rats. HRV indices were recorded using the Physiobelt 2.5.1 complex (Neurobotics, Russia) and analyzed by statistical, geometric and spectral indicators. Taftsin-PGP was administered intraperitoneally at doses of 80, 250 and 750 μg/kg once in a volume of 1 μg/kg. The study was performed in 4 stages: 1 – after adaptation to the device (before the introduction of the peptide), 2 – 15 minutes after the introduction of the peptide, 3 – after physical exertion (2-minute treadmill run), 4 – after a 15-minute rest. Results: At a dose of 80 μg/kg, taftsin-PGP had a pronounced adaptogenic effect in the form of maintaining the initial level of functioning of regulatory mechanisms both during physical exertion and during recovery. At a dose of 250 μg/kg, taftcin-PGP led to disorganization of autonomic regulation at the level of the autonomous and central circuits of heart rate regulation. The introduction of the peptide at a dose of 750 μg/kg stabilized the mechanisms of regulation of heart rate with increased physical activity, but caused an imbalance in the regulation of heart rate during recovery. Conclusion: Intraperitoneal administration of taftsin-PGP to Wistar rats had a dose-dependent and multidirectional effect on the regulation of heart rate at all stages of the experiment: at rest (15 minutes after administration), after physical exertion and during recovery.