Effect of chronic treatment with the protein kinase C inhibitor staurosporine on the acquisition and expression of contextual fear conditioning.

The present study investigated the effects of acute and chronic administration of the protein kinase C inhibitor, staurosporine, on the acquisition and expression of conditioned freezing behavior, an index of anxiety induced by conditioned fear stress. Results revealed that acute staurosporine (0.01 and 0.1 mg/kg, i.p.) did not affect either acquisition or expression of conditioned freezing. Chronic staurosporine administration (0.01 or 0.1 mg/kg, i.p., for 14 days) significantly reduced the acquisition of conditioned freezing at a dose of 0.1 mg/kg, but failed to affect the expression of conditioned freezing at any dose. These results suggest the involvement of protein kinase C in synaptic and cellular plasticity underlying emotional learning and memory.