Acute amphetamine and/or phencyclidine effects on the dopamine receptor specific binding in the rat brain.
Psychotic-like behaviour was induced in rats with a single i.p. injection of AMPH (20 mg/kg b.w.) and/or PCP (10 mg/kg b.w.). The D1 and D2 dopamine receptor (DAR) specific binding of [3H]SCH 23390 and [3H]spiperone, respectively, during the 120 min period upon the treatment was examined on cryosections using computerized scanning and image analysis. AMPH, alone or in combination with PCP, induced a transient decrease of the D1 receptor specific binding in the striatum (30 min; AMPH, -18%; AMPH+PCP, -31%) and nucleus accumbens (30 min; AMPH, -30%; AMPH+PCP, -40%), which was completely abolished at the 120 min point. Only AMPH persistently elevated nigral D1 receptor specific binding. PCP-induced striatal and accumbal D1 receptor down-regulation was intensive throughout the 120 min period, while in the s. nigra it was non-significant. A significant increase of the D2 receptor specific binding was observed only 30 min after the treatment in striatum (AMPH, 15%; PCP, 16%; AMPH+PCP, 13%) and n. accumbens (AMPH, 16%). These alterations of DAR specific binding may reflect a regulation of the DAR and the changes in nigrostriatal and mesolimbic DA-ergic neurotransmission during an intensive drug-induced psychotic-like behavioral expression.
Tomić
M
M
Institute for Biological Research, Belgrade, Yugoslavia.
Vukosavić
S
S
Joksimović
J
J
D000661:Amphetamine / Q000494:pharmacology*; D000818:Animals; D001921:Brain / Q000187:drug effects* / Q000378:metabolism; D000697:Central Nervous System Stimulants / Q000494:pharmacology*; D006213:Hallucinogens / Q000494:pharmacology*; D008297:Male; D010622:Phencyclidine / Q000494:pharmacology*; D051381:Rats; D017447:Receptors, Dopamine D1 / Q000187:drug effects* / Q000378:metabolism; D017448:Receptors, Dopamine D2 / Q000187:drug effects* / Q000378:metabolism
D000697:Central Nervous System Stimulants; D006213:Hallucinogens; D017447:Receptors, Dopamine D1; D017448:Receptors, Dopamine D2; D000661:Amphetamine; D010622:Phencyclidine