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Purpose of the study. The aim of this work was to study the effect of conservation in various cryoprotectants on the biomechanical and morphological properties of the umbilical cord (UCA) arteries.Materials and methods. The material for this work was 12 umbilical arteries, which were divided into 4 study groups: (1) native UCA – control without freezing; (2) APC frozen in 5 % dextran with the addition of dimethyl sulfoxide (DMSO) to 10 % and 7.5 % human serum albumin (HSA); (3) APC frozen in glycerin and (4) UCA frozen in propanediol. For all groups, morphological and biomechanical studies were carried out. The statistical data were processed using the GraphPad Prism 9.2.0 program. Analysis of variance was used to find significant differences.Results. Freezing with 5 % dextran, 10 % DMSO and 7.5 % human albumin did not lead to significant changes in the morphology of vascular tissue compared to control. The conserved vascular tissue retains a moderate level of type I collagen, regardless of the method of conservation. The presence of statistically significant differences between the control and frozen UCAs was shown for Young's modulus (p < 0.05; 6.9 [6.8; 7.0] for the native artery; 2.3 [2.0; 2.6] for the artery preserved with the use of dextran, DMSO and human albumin; 2.3 [1.4; 3.2] for the artery preserved in glycerin and 0.8 [0.6; 1.0] – in propanediol, respectively).Conclusion. 1) Freezing and storage of UCA at 5 % dextran, 10 % DMSO and 7.5 % HSA does not lead to a significant change in the morphology of vascular membranes and cell nuclei; 2) The preservation of type I collagen according to the results of IHC is qualitatively reduced from a conditional indicator of +2 to +1 for frozen agroindustrial complexes compared with control ones; 3) Conservation leads to a significant decrease in the modulus of elasticity of the walls of the agroindustrial complex compared with control vessels (p < 0.05).

Aim. To develop a safe protocol for cryopreservation of segments of iliac arteries straight after their retrieval from post-mortem donor with the use of polydimethylsiloxane as a coolant and cryoprotectant.Materials and methods. Eleven segments of iliac arteries were retrieved from post-mortem donor and divided into four groups including control. Based on preliminary heat and cold transfer mathematical modeling and tests with tissueequivalent phantom arterial segments were placed on plastic mounts and cryopreserved by following protocol: groups 1 and 2 were immersed in polydimethylsiloxane and cooled rapidly at 180 °С/min to –75 °С. Group 3 segments were cryopreserved at 1,6 °С/min in PDMS – fi lled cryo-container placed in the freezer at –80 °С. All segments were defrosted by immersion in PDMS at +24 °С and then examined for morphology changes by histological methods and SEM. EDS analysis with the use of AzTech software also was performed for Si – content evaluation. Restricted biomechanical tests were conducted for group 2 segments.Results. There were no signifi cant morphological differences between segments of the control and cryopreserved groups except for the segment with slow cooling.Conclusion. Mobile cryopreservation may allow increasing the effi ciency of retrieval of a large number of donor tissues for possible later use in the processing of bioprostheses of blood vessels; or, after decellularization, as well as tissue-specifi c matrices for tissue-engineering blood vessels.