title: Effects of p-chlorophenylalanine-induced depletion of brain serotonin on retrieval of appetitive and aversive memories.
abstract: This study examined whether depletion of central serotonin produces an improved retrieval of aversive memories in the same way as pre-exposure to inescapable footshocks, in rats. Animals conditioned in a T-maze with appetitive (10% sucrose) and aversive (2.0 mA footshock) events were given i.c.v. 24 hr later a single dose of p-chlorophenylalanine (p-CPA). (100, 200, 400 micrograms/rat) or drug vehicle. The retention performance and activity were assessed 48 hr after treatment with this depletor. While lower doses of p-CPA selectively reduced serotonin levels in striatum and anterior cortex, higher doses reduced both serotonin and norepinephrine levels in hippocampus in a dose-dependent fashion. The depletor however, failed to produce a differential improvement of aversive memory retrieval. On the contrary, p-CPA reduced the latency to enter both, previously shocked and appetitively reinforced, goalboxes. The enhanced traversing behaviour in T-maze, together with an increased central entry in the open field that observed in depleted groups, might suggest an anxiolytic activity of p-CPA.
authors.affiliation: Department of Psychiatry, Kasturba Hospital, Manipal, India.
authors.forename: K B
authors.initials: KB
authors.lastname: Kumar
authors.forename: K
authors.initials: K
authors.lastname: Nalini
authors.forename: K S
authors.initials: KS
authors.lastname: Karanth
mesh_terms: D000818:Animals; D001070:Appetitive Behavior / Q000187:drug effects / Q000502:physiology; D001921:Brain / Q000187:drug effects* / Q000502:physiology*; D010134:Fenclonine / Q000494:pharmacology*; D008297:Male; D008568:Memory / Q000187:drug effects / Q000502:physiology; D051381:Rats; D017208:Rats, Wistar; D012701:Serotonin / Q000378:metabolism*; D018490:Serotonin Agents / Q000494:pharmacology*; D014018:Tissue Distribution
chemical_list: D018490:Serotonin Agents; D012701:Serotonin; D010134:Fenclonine