Aim.To evaluate the effects of long-term wet treatment of porcine aortic wall fragments with biocidal solutions (glutaraldehyde, antibiotics, alcohol-glycerin mixture, complex alcohol solution (CAS)) on the severity of degradation of samples’ connective matrix and their long-term ability to accumulate calcium during subcutaneous implantation in laboratory rats (1 and 3 months).Methods.Histological analysis of freshly collected material was performed after 50 days of treatment with various biocidal solutions and after subcutaneous implantation of samples in small laboratory animals at 1 and 3 months. Calcium was measured with the atomic absorption spectroscopy after 3 months of subcutaneous implantation.Results.Histological analysis reported that connective matrix of samples treated with glutaraldehyde, antibiotics, and CAS was similar to the native one (with the exception of partial loss of cellular components in samples). After 1 month of implantation, a moderate degradation of connective tissue was found. The treatment with the alcohol-glycerin mixture was associated with the most severe degradation. After 3 months of implantation, glutaraldehyde-treated samples had the most preserved connective matrix, while alcohol-glycerin-treated samples demonstrated severe connective matrix injury. However, severe calcific deposits were found in samples treated with glutaraldehyde, whereas mild ones were detected in samples treated with alcohol-glycerin. Atomic absorption spectroscopy reported that calcific deposits in Cas- and alcohol-glycerin-treated samples were 2.3 and 1.8 times lower than those in glutaraldehyde-treated samples. The calcium content in samples treated with antibiotics did not differ significantly from those in glutaraldehyde-treated samplesConclusion.The comprehensive analysis of the effects of various treatment media on the stability of connective matrix to subsequent degradation and its ability to accumulate calcium found that CAS was the most preferred medium for long-term wet treatment of xenoprosthetic vascular tissue.