Stimulation of plasma fibronectin production in mice by muroctasin.

The production of plasma fibronectin (PFN) in mice treated subcutaneously with N2-[(N-acetylmuramoyl)-L-alanyl-D-isoglutaminyl]-N6-stearoyl-L-lysine (MDP-Lys(L18), muroctasin), was examined. The plasma levels of PFN in mice increased significantly by treatment with a single dose of 10 to 100 micrograms/mouse of MDP-Lys(L18). A slight strain difference in the PFN levels among Std: ddY, C3H/He, and DBA 2 mice was observed: the percent increases at the maximal level in Std: ddY, C3H/He, and DBA/2 mice were 21.6, 19.9, and 10.4, respectively. In Std: ddY mice, the concentration of PFN reached the maximal level at 15 h post-treatment, and decreased gradually of the normal level by 48 h. These results indicate that MDP-Lys(L18) stimulates the PFN production in mice.