K-252a specifically inhibits the survival and morphological differentiation of NGF-dependent neurons in primary cultures of human dorsal root ganglia.

We have measured neurofilament protein expression in cultures of human dorsal root ganglia (DRG) grown in both the presence and absence of nerve growth factor (NGF). Cultures established from DRG of 8-13 weeks gestation contained populations of both NGF-dependent and -independent neurofilament-positive cells. A recently described kinase inhibitor named K-252a inhibited NGF-dependent increases in neurofilament protein expression with half-maximal and maximal inhibition apparent at concentrations of 6 and 25 nM. At up to 50 nM, K-252a had no effect on neurofilament protein expression from NGF-independent neurons.