Memory impairment induced by combined disturbance of noradrenergic and dopaminergic neurotransmissions: effects of nootropic drugs.
The effect of the combined application of the alpha 2-adrenoreceptor agonist clonidine and of the dopaminergic blocker haloperidol on the memory processes was tested on albino rats. The changes in the memory were studied using the following methods: two-way active avoidance with negative reinforcement (shuttle-box) and passive avoidance (step-through). Both clonidine (0.05 mg/kg) and haloperidol (0.5 mg/kg), injected intraperitoneally immediately after the end of the training session, slightly impaired retention in the memory tests used with both training methods. Their combined application, however, caused a marked amnesia. This amnesia model was used to study the effects of the nootropic drugs: adafenoxate and the newly-synthesized compound benzoyl-1, 4-dipyrolydinone (p-P). Administered orally in a dose of 100 mg/kg for 5 days prior to the training session, both adafenoxate and p-P fully eliminate the amnesia caused by the combined application of clonidine and haloperidol. The paper discusses the role of the noradrenergic and dopaminergic neurotransmitter systems for the amnestic effect of the clonidine + haloperidol combination, as well as for the favourable effect on the cognitive functions of the tested nootropic drugs adafenoxate and p-p.
Lazarova-Bakarova
M B
MB
Institute of Physiology, Bulgarian Academy of Sciences.
Petkova
B P
BP
Todorov
I K
IK
Petkov
V D
VD
D000818:Animals; D001362:Avoidance Learning / Q000187:drug effects; D001565:Benzoates / Q000494:pharmacology; D002491:Central Nervous System Agents / Q000494:pharmacology*; D003000:Clonidine / Q000494:pharmacology; D004298:Dopamine / Q000502:physiology*; D006220:Haloperidol / Q000494:pharmacology; D008297:Male; D002504:Meclofenoxate / Q000031:analogs & derivatives / Q000494:pharmacology; D008569:Memory Disorders / Q000139:chemically induced* / Q000523:psychology; D009638:Norepinephrine / Q000502:physiology*; D011678:Punishment; D011758:Pyrroles / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D009435:Synaptic Transmission / Q000187:drug effects / Q000502:physiology*
D001565:Benzoates; D002491:Central Nervous System Agents; D011758:Pyrroles; C074605:benzoyl-1,4-dipyrrolidinone; C054061:adafenoxate; D002504:Meclofenoxate; D006220:Haloperidol; D003000:Clonidine; D004298:Dopamine; D009638:Norepinephrine