Fig. 1

Recording of noradrenergic neurons in the locus coeruleus (LC) of wild-type (WT) and Ndn +m/−p mice. a Representative images of LC norepinephrine (NE) neurons of WT and Ndn +m/−p mice. Necdin was abundant in the LC-NE neurons of WT mice. b Identification of LC neurons in a sagittal brainstem slice. A non-fixed slice with a recording of LC neurons at high magnification (i). Fluorescence microscopy photographs of a brainstem slice stained with anti-tyrosine hydroxylase (TH) antibody (ii), biocytin (iii), and the merged image (iv). c A representative current recording from the LC-NE neuron showed spontaneous firing of action potentials (APs). d Representative tracings of spontaneous APs of LC-NE neurons. e The spontaneous AP frequency was significantly lower for LC-NE neurons in Ndn +m/−p (n = 26 cells from 11 animals) than those in WT mice (n = 35 cells in 12 animals). Statistical analyses were performed using Student’s t test. Data are presented as mean ± SEM, *P < 0.05