On the growth of cultured bovine aortic endothelial cells. Preliminary observations of ultrastructural (freeze-etching) morphology and quantitation of growth speed at phase-contrast microscopic examination: Effect of glycosaminoglycans (GAGs) [Sull' accrescimento in coltura di cellule endoteliali di aorta bovina. Osservazioni preliminari di morfologia ultrastrutturale al crio-decappaggio e quantizzazione della velocita' di crescita in microscopia a contrasto di fase: effetto di glicosaminoglicani]

Bovine aortic endothelial cells (BAEC), detached from thoracic aorta by collagenase treatment, have been studied after adding a mixture of glycosaminoglycans (GAGs) (the composition of which has been studied by Casu et al. -6), at different concentrations. GAGs at the concentration of 90 mg/100 ml of medium (Dulbecco's modification of Eagle's MEM with 10% foetal calf serum) produced an increase in the growth speed. We have quantitized these data both by counting the number of cells 24 h after trypsinization in phase-contrast-microscopy, and by measuring the time necessary to reach a certain number of influences. Ultrastructural observation at transmission electron microscope after freeze-etching preparation, didn't show any relevant modification either in the organization of cell membrane or in the cytoplasmatic structures. An increase of "vesicular openings" ("pits") on the plasma-membrane was evident.