[Fibronectin in the structures of total preparations of loose connective tissue]

A comparative study of fibronectin localization in the cells and paraplastic structures of total film loose connective tissue preparations obtained from different animal species (mice, rats, guinea-pigs, golden hamsters) made it possible to reveal some regularities. In mice and rats, protein was found in fibroblast cytoplasm (or on its surface) in the form of dots and dotted lines. In golden hamsters, it was found in the form of larger round loci, whereas in guinea-pigs, fibronectin was diffused. In glycokalyx, fibronectin was detectable on the surface of reticular fibres in the form of ununiform accumulations. The greatest amount of protein was found in the cross-zones of reticular fibres, where fibroblasts actively synthesizing fibronectin are located.