Delayed effects of amphetamine or phencyclidine: interaction of food deprivation, stress and dose.
J R Coveney, S B Sparber
Pharmacology, Biochemistry, and Behavior July 1990 DOI: 10.1016/0091-3057(90)90239-e (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Experimental animal study Peer reviewed |
|---|---|
| Population | Male rats maintained at 85% of initial free-feeding weights |
| Interventions | Phencyclidine (PCP) hydrochloride Dextroamphetamine sulfate |
| Dose | PCP HCl 12 mg/kg; PCP HCl 2 or 4 mg/kg; PCP HCl 4 or 8 mg/kg; dextroamphetamine sulfate 3.2 or 6.4 mg/kg |
| Duration | Six consecutive daily injections; footshock testing eight days after the last injection; food deprivation for six or nine consecutive days |
| Key findings | Acute footshock stress in PCP-treated rats raised fat PCP levels 28% and lowered blood levels 18% without significantly changing brain levels, indicating redistribution to fat rather than brain. PCP at 4 mg/kg altered exploratory behavior relative to saline controls once food deprivation brought rats to about 70% of initial body weight, a result the authors report was replicated. |
Abstract
Tritium-labelled phencyclidine (PCP) hydrochloride (12 mg/kg) was injected SC for six consecutive days into two groups of eight male rats maintained at 85% of their initial free-feeding weights. Eight days after the last injection, electric footshock raised fat levels of PCP 28% over nonshocked controls, and lowered blood levels 18%, but did not alter brain levels of the drug significantly. Thus, application of an acute stressor does result in redistribution of tissue stores of phencyclidine as predicted in the literature; however, the direction of the redistributions was to fat, rather than to brain. To explore the relation of a long-term stressor (one that eliminates adipose tissue as a sink for mobilized PCP), exploratory behavior was evaluated in male rats during six days of food deprivation commencing after six daily injections of PCP HCl (2 or 4 mg/kg, SC). Exploratory behavior of the 4 mg/kg dose group was abruptly altered, compared to saline controls, at six days of food deprivation, when the rats' body weights were about 70% of initial weights and when body fat would be severely reduced or depleted. To assess replicability and generalizability of this phenomenon, PCP HCl (4 or 8 mg/kg, SC) or dextroamphetamine sulfate (3.2 or 6.4 mg/kg, SC) was injected into male rats for six days and food deprivation followed afterward for nine consecutive days, or until similar body weight reductions as in the first experiment were achieved. Again, exploratory behavior was altered in comparison to saline controls in phencyclidine-treated rats (at the 4 mg/kg dose level) when rats reached about 70% of initial weights.(ABSTRACT TRUNCATED AT 250 WORDS)