Abstract: A novel use of an inhibitor of protein kinase C (PKC) for suppressing the sustained slow postsynaptic excitation (SSPE) caused by prolonged stimulation of synaptic inputs to intrinsic primary afferent neurons (IPANs), is provided. Since the generation of SSPE requires a phosphorylation step mediated by protein kinase C, PKC inhibitors, such as staurosporine, RO31-8220 or calphostin C is useful for a method for the treatment of a patient having a need to suppress the sustained slow postsynaptic excitation (SSPE) caused by prolonged stimulation of synaptic inputs to intrinsic primary afferent neurons (IPANs), such as intestinal hypersensitivity, irritable bowel syndrome (IBS), non-ulcer dyspepsia, or other conditions that may derive from long-term changes in the behavior of enteric neurons.