title: Physiological properties of ascending locus coeruleus axons in the squirrel monkey.
abstract: Discharge activity was recorded extracellularly from individual neurons of the nucleus locus coeruleus in anesthetized squirrel monkeys. These cells exhibited long-duration (2-3 ms) action potentials and discharged spontaneously in a slow (0.2-2 Hz) irregular fashion. Stimulation of the lateral hypothalamus evoked antidromic responses at latencies of 10-20 ms, indicating conduction velocities of over 1 m/s in some cases. The mean refractory period for these axons was 2.6 ms. When the rate of hypothalamic stimulation was increased from 1 to 10 Hz there was a 15-20% increase in antidromic latencies. These properties are similar to those previously observed for rat LC neurons, except that conduction velocities are higher in monkey.
mesh_terms: D000818:Animals; D001931:Brain Mapping; D005071:Evoked Potentials; D007026:Hypothalamic Area, Lateral / Q000502:physiology*; D008125:Locus Coeruleus / Q000502:physiology*; D009431:Neural Conduction; D009434:Neural Pathways / Q000502:physiology; D011930:Reaction Time / Q000502:physiology; D012032:Refractory Period, Electrophysiological; D012453:Saimiri / Q000502:physiology