[Ultrastructural changes of veins in several variants of cryopreservation]

The findings of ultrastructural analysis demonstrated essential changes in connective tissue cells and noncellular elements of veins after their cryopreservation at -50 degrees C and -196 degrees C. Contraction and round-up of endotheliocytes, disruption of their connections with basement membrane leading to subendothelial space widening, cytoplasm vacuolization and focal destruction of luminal plasmalemma are typical and general changes caused by cryopreservation. Dystrophy of different grades developed in connective tissues of media and adventitia. Deeper freezing negatively affects structural integrity of venous tissues. After the use of conserving solutions (Eurocollins and Scientific Research Institute of Traumatology and Orthopaedics) necrotized endotheliocytes were absent and endothelial lining was preserved in major part of the vein surface studied even following its deep freezing which supports the conclusion on the cryoprotective effect of the solutions.