In rats, nerve ligation (a model of peripheral nerve injury) increases brain-derived neurotrophic factor (BDNF), which causes a reduction in both mRNA and expression of the BK channel in the DRG, leading to an increase in excitatory transmission (Scholz and Woolf, 2007; Furukawa et al., 2008). The gene discussed is BDNF; the disease is peripheral nerve injury.