The disintegrin kistrin inhibits neurite extension from spiral ganglion explants cultured on laminin

The influence of laminin-1 (LN) and tenascin-C (TN), extracellular matrix m olecules expressed spatially and temporally along the neural growth route f rom spiral ganglion (SG) neurons to the cochlear sensory cells, was evaluat ed in cultured SG explants from postnatal day 4 rats. Increasing concentrat ions of LN resulted in a strong, dose-dependent increase in the length of n eurites and in a higher number of neural processes, while varying TN concen trations had relatively minor effects on both parameters. The results sugge st differential receptor activation by LN and TN. When explants grown on LN were treated with Kistrin, an inhibitor of the alphav beta3 integrin, the LN-induced increase in neurite length was reduced in a dose-dependent manne r. However, the number of extending neurites was not affected, indicating t hat different receptors mediate this response, perhaps by increasing neuron al survival, Copyright (C) 2001 S. Karger AG, Basel.