AGE-RELATED-CHANGES OF DRG NEURONAL ATTACHMENT TO EXTRACELLULAR-MATRIX PROTEINS INVITRO

ATTACHMENT of dorsal root ganglion (DRG) neurones from 3-month-old (yo ung adult) and 24-month-old (aged) mice to the following substrates wa s evaluated after 6 h in culture: (1) poly-L-lysine (PL), (2) PL + typ e I collagen (CL-I), (3) PL + type IV collagen (CL-IV), (4) PL + lamin in (LM) and (5) PL + fibronectin (FN). In the young adult mice, each s ubstrate coated onto PL, significantly increased the ratio of attachme nt, compared with PL alone. In the aged mice, CL-I and LM, but not CL- N or FN improved the attachment. There was no difference in cell survi val or neurite extension after 48 h in culture between the two groups of mice. These results suggest that ageing causes selective changes of the neuronal cell-surface receptors respective to extracellular matri x proteins such as CL-IV and FN.