INHIBITION OF NGF-INDUCED NEURITE OUTGROWTH OF PC12 CELLS BY BACILLUS-CEREUS SPHINGOMYELINASE, A BACTERIAL HEMOLYSIN

Sphingomyelinase of Bacillus cereus, a bacterial hemolysin, reduced ne rve growth factor (NGF)-induced neurite outgrowth of PC12 cells in a d ose-dependent manner. At 200 mU/ml, sphingomyelinase repressed half th e neurite outgrowth of the cells at 250 ng/ml NGF. The c-fos superindu ction, one of the early responses induced by NGF, was not influenced b y this treatment, suggesting that the repression by sphingomyelinase o ccurred via a protein kinase C-independent pathway.