Serotonin depletion causes long-term reduction of exploration in the rat.
This study assessed the effects of central serotonergic depletion on exploratory activity at baseline, as well as after administration of d-amphetamine or the anxiogenic beta-carboline FG-7142. Intraventricular 5,7-dihydroxytryptamine (5,7-DHT) induced an almost complete depletion of serotonin [5-hydroxytryptamine (5-HT)] in the medial prefrontal cortex, nucleus accumbens, medial corpus striatum, and hippocampus with no changes in norepinephrine, dopamine or dihydroxyphenylacetic acid concentrations. 5-HT-depleted rats demonstrated reduced spontaneous and d-amphetamine-augmented exploration 3-10 weeks postoperatively. An effect on FG-7142-induced inhibition of exploratory activity was not apparent. These data implicate 5-HT systems in the expression of different aspects of exploratory and amphetamine-augmented motor behaviors.
Lipska
B K
BK
Clinical Brain Disorders Branch, National Institute of Mental Health, St. Elizabeths, Washington, DC 20032.
Jaskiw
G E
GE
Arya
A
A
Weinberger
D R
DR
D015116:5,7-Dihydroxytryptamine / Q000494:pharmacology; D000818:Animals; D015306:Biogenic Monoamines / Q000378:metabolism; D002243:Carbolines / Q000494:pharmacology; D003913:Dextroamphetamine / Q000494:pharmacology; D005106:Exploratory Behavior / Q000187:drug effects*; D008297:Male; D009043:Motor Activity / Q000187:drug effects; D051381:Rats; D017207:Rats, Sprague-Dawley; D012701:Serotonin / Q000502:physiology*
D015306:Biogenic Monoamines; D002243:Carbolines; D015116:5,7-Dihydroxytryptamine; D012701:Serotonin; C035874:FG 7142; D003913:Dextroamphetamine