Figure 3 |.

Loss of hypocretin neurons and increase in histamine neurons in narcolepsy. a | Number and distribution of hypocretin neurons, and a representative cell staining of brain slices from a healthy control (left) and an individual with narcolepsy (right). Scale bars = 25 μm. b | Number and distribution of histamine neurons, and a representative cell staining from a healthy control (left) and an individual with narcolepsy (right). Scale bars = 50 μm. Part a reprinted with permission from Elsevier © Thannickal, T. C. et al. Reduced number of hypocretin neurons in human narcolepsy. Neuron 27, 469–474 (2000). Part b adapted with permission from John Wiley & Sons © John, J. et al. Ann. Neurol. 74, 786–793 (2013).