TY - JOUR
T1 - Social interaction and cortisol treatment increase cell addition and radial glia fiber density in the diencephalic periventricular zone of adult electric fish, Apteronotus leptorhynchus
AU - Dunlap, Kent D.
AU - Castellano, James F.
AU - Prendaj, Erealda
N1 - Funding Information:
The monoclonal antibody to vimentin was developed by A. Alvarez-Buylla and obtained from the Developmental Hybridoma Bank at the University of Iowa. C. Pytte and J. Kirn provided technical and conceptual advice, E. McCarthy collected data for Experiment 7, J. Nord assisted with animal care. V. Salvador, and S. St. Jean assisted with logistics. This work was supported by a grant from NIH (R03-MH066898-01) to KDD and the HHMI to Trinity College.
PY - 2006/6
Y1 - 2006/6
N2 - In electric fish, Apteronotus leptorhynchus, both long-term social interaction and cortisol treatment potentiates chirping, an electrocommunication behavior that functions in aggression. Chirping is controlled by the diencephalic prepacemaker nucleus (PPn-C) located just lateral to the ventricle. Cells born in adult proliferative zones such as the periventricular zone (PVZ) can migrate along radial glial fibers to other brain regions, including the PPn-C. We examined whether social interactions or cortisol treatment influenced cell addition and radial glia fiber formation by (1) pairing fish (4 or 7 days) or (2) implanting fish with cortisol (7 or 14 days). Adult fish were injected with bromodeoxyuridine 3 days before sacrifice to mark cells that were recently added. Other fish were sacrificed after 1 or 7 days of treatment to examine vimentin immunoreactivity (IR), a measure of radial glial fiber density. Paired fish had more cell addition than isolated fish at 7 days, coinciding temporally with the onset of socially induced increase in chirping behavior. Paired fish also had higher vimentin IR at 1 and 7 days. For both cell addition and vimentin IR, the effect was regionally specific, increasing in the PVZ adjacent to the PPn-C, but not in surrounding regions. Cortisol increased cell addition at 7 days, correlating with the onset of cortisol-induced changes in chirping, and in a regionally specific manner. Cortisol for 14 days increased cell addition, and cortisol for 7 days increased vimentin IR but in a regionally non-specific manner. The correlation between treatment-induced changes in chirping and regionally specific increases in cell addition, and radial glial fiber formation suggests a causal relationship between such behavioral and brain plasticity in adults, but this hypothesis will require further testing.
AB - In electric fish, Apteronotus leptorhynchus, both long-term social interaction and cortisol treatment potentiates chirping, an electrocommunication behavior that functions in aggression. Chirping is controlled by the diencephalic prepacemaker nucleus (PPn-C) located just lateral to the ventricle. Cells born in adult proliferative zones such as the periventricular zone (PVZ) can migrate along radial glial fibers to other brain regions, including the PPn-C. We examined whether social interactions or cortisol treatment influenced cell addition and radial glia fiber formation by (1) pairing fish (4 or 7 days) or (2) implanting fish with cortisol (7 or 14 days). Adult fish were injected with bromodeoxyuridine 3 days before sacrifice to mark cells that were recently added. Other fish were sacrificed after 1 or 7 days of treatment to examine vimentin immunoreactivity (IR), a measure of radial glial fiber density. Paired fish had more cell addition than isolated fish at 7 days, coinciding temporally with the onset of socially induced increase in chirping behavior. Paired fish also had higher vimentin IR at 1 and 7 days. For both cell addition and vimentin IR, the effect was regionally specific, increasing in the PVZ adjacent to the PPn-C, but not in surrounding regions. Cortisol increased cell addition at 7 days, correlating with the onset of cortisol-induced changes in chirping, and in a regionally specific manner. Cortisol for 14 days increased cell addition, and cortisol for 7 days increased vimentin IR but in a regionally non-specific manner. The correlation between treatment-induced changes in chirping and regionally specific increases in cell addition, and radial glial fiber formation suggests a causal relationship between such behavioral and brain plasticity in adults, but this hypothesis will require further testing.
KW - Apteronotus leptorhynchus
KW - BrdU
KW - Cell addition
KW - Cortisol
KW - Electric fish
KW - Electrocommunication
KW - Glucocorticoids
KW - Radial glia
KW - Social behavior
KW - Vimentin
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UR - http://www.scopus.com/inward/citedby.url?scp=33646840477&partnerID=8YFLogxK
U2 - 10.1016/j.yhbeh.2006.01.003
DO - 10.1016/j.yhbeh.2006.01.003
M3 - Article
C2 - 16584732
AN - SCOPUS:33646840477
SN - 0018-506X
VL - 50
SP - 10
EP - 17
JO - Hormones and Behavior
JF - Hormones and Behavior
IS - 1
ER -