We found that vagal hyperactivity produced by ventromedial hypothalamic (VMH) lesions stimulated cell proliferation of rat pancreatic islet B through a cholinergic receptor mechanism. Previously, we developed a new technique regarding high-quality RNA extraction from rat pancreas for cDNA microarray analysis, and thereby, we found that VMH lesions may change the expression of cell proliferation-related genes and neuron-related genes in a rat pancreas, using DNA microarray and real-time polymerase chain reaction. We believes that these new gene network analysis will lead to Diabetes MellitusTreatment or Pancreatic Cancer.