Effect of human umbilical cord blood mononuclear cells on rat cardiovascular system in subchronic experiment

Objective. To study the effects of human umbilical cord blood mononuclear cells (HUCB-MNCs) on functional state of cardiovascular system in healthy rats in subchronic experiment. Material and methods. The study enrolled 60 Wistar rats weighing 180 g (10 per a group) which were injected intravenously with transport medium for 60 days at intervals of 11—12 days (control group) and experimental HUCB-MNCs in dosages of 400 and 800 million cells /kg body weight. After 60 days, we screened heart rate (HR) and blood pressure before and after physical activity (free swimming for 2 minutes at a temperature of 38 °C). Doppler ultrasound of hind limb vessels at rest was performed. Median (Me), upper and lower quartiles (C25—C75) were calculated. We tested hypotheses using the Mann—Whitney criterion. Results. There were no significant changes in heart rate and blood pressure at rest under cell therapy. Males (HR): control 421 (403—432), “400 million” 455 (402—467), “800 million” 429 (423—436); females: control 405 (382—431), “400 million” 405 (389—428), “800 million” 404 (367—414). Under physical activity, males and females with dosage 800 million cells/kg showed significantly (p<0.001) lower heart rate by 8.0%. Significantly (p<0.05) higher blood flow velocity in vessels of lower extremities may indicate multiple functioning capillaries. At the same time, lower Gosling index in the experimental group (p<0.05) potentially indicates higher elasticity of vascular walls. Conclusion. Intravenous injection of HUCB-MNCs 800 million cells / kg improves cardiovascular function with higher ability to tolerate physical exertion and better peripheral hemodynamics.