Abstract
Cell surface material and contact specializations were observed in reaggregates of cells from 7-day embryonic chick hearts. Ruthenium red- or lanthanum nitrate-staining surface material was absent from cells freshly dissociated with trypsin. This staining reaction of surface acidic glycoproteins returned during the third hr of culture. Tight, gap and adherent junctions were observed between contiguous myocardial cells prior to the recovery of the surface coat. We suggest that the surface coat stainable with tracers for acid mucopolysaccharides is involved in cell adhesion, but initial cell attachment may be mediated by the assembly of these attachment devices.
