title: Correlative firing patterns of serotonergic neurons in rat dorsal raphe nucleus.
abstract: In this study, local neuronal interactions in the midbrain dorsal raphe nucleus (DRN) were analyzed by the use of autocorrelation and cross-correlation histograms. The autocorrelograms of serotonin (5-hydroxytryptamine; 5-HT)-containing cells showed an initial trough and subsequent periodicity which corresponded to their regular rhythmic firing pattern. Cross-correlograms revealed that all adjacent 5-HT neurons recorded from single micropipettes displayed complicated patterns of functional interactions. The interactions could be grouped into the following categories: (1) synchronization (interspike intervals less than 10 msec), (2) synchronization and direct inhibition, (3) synchronization and mutual inhibition. In contrast, cross-correlograms generated from adjacent neuronal pairs consisting of one 5-HT cell and one non-5-HT neuron or from non-adjacent 5-HT neuronal pairs usually failed to show functional interactions. The results of the present study are consistent with previous findings of a powerful auto-and mutual regulatory system for 5-HT neurons in the DRN.
mesh_terms: D000818:Animals; D001933:Brain Stem / Q000502:physiology*; D003712:Dendrites / Q000502:physiology; D005071:Evoked Potentials; D008297:Male; D009433:Neural Inhibition; D009474:Neurons / Q000502:physiology; D011903:Raphe Nuclei / Q000502:physiology*; D051381:Rats; D011919:Rats, Inbred Strains; D012701:Serotonin / Q000502:physiology*; D013569:Synapses / Q000502:physiology; D009435:Synaptic Transmission
chemical_list: D012701:Serotonin