Whisker Deflection Increase Interleukin-1β Immunoreactive Cells in The Barrel Field
X. Guan, L. Churchill, J.M. Krueger
Washington State University, College of Veterinary Medicine
Interleukin-1 (IL-1) is a well characterized sleep regulatory substance (SRS). One of the sleep hypotheses is that neuronal activity enhances the production of SRSs in cortical neurons and they in turn drive the state shift within the neuronal group where they were produced. In consistent with this theory, whisker stimulation elicited a greater increase in electroencephalogram (EEG) slow wave activity (SWA) during non-rapid eye movement sleep (NREM) sleep in the stimulated hemisphere than in the control hemisphere. Unilateral whisker deflection increased the number of TNFα and NGF-immunoreactive cells in the barrel field. In this study, we tested the hypothesis that the production of IL1β is activity dependent using immunohistochemistry method combined with unilateral whisker deflection. After 2 hour of manual whisker deflection, the stimulated cortical columns as evident by fos activation in an adjacent section showed an increase in the number of IL1-IR cells in layer V when compared to the un-stimulated columns. These results add more evidence to the hypothesis that sleep is an activity dependent event driven by SRSs.