Effect of Leu-enkephalin on the memory reactivation produced by blockade of the benzodiazepine/GABA-chloride ionophore receptor complex.
This investigation sought to characterize the interaction between GABA/benzodiazepine and opioid systems in memory retrieval deficit induced by detaining an animal in the training apparatus after acquisition. Mice pretreated with saline or Leu-enkephalin (0.2 mg/kg) were trained in one-trial passive avoidance test with following detention. Pre-testing administration of bicuculline (1 mg/kg), picrotoxin (1 mg/kg), or flumazenil (10 mg/kg) produced the memory-enhancing effect in the saline-pretreated mice. Pretraining treatment with Leu-enkephalin blocked the reactivation of memory produced by bicuculline and picrotoxin, but not flumazenil. The present investigation suggest that both benzodiazepine/GABA and opioid systems are important modulators of memory retrieval and that a specific interaction between these systems is responsible for the observed recovery of impaired memory trace.
Dubrovina
N I
NI
Department of Central Mechanisms of Regulation, Siberian Branch of Russian Academy of Medical Sciences, Novosibirsk.
Ilyutchenok RYu
D000704:Analysis of Variance; D000818:Animals; D001362:Avoidance Learning / Q000187:drug effects; D001640:Bicuculline / Q000494:pharmacology; D004743:Enkephalin, Leucine / Q000494:pharmacology*; D005442:Flumazenil / Q000494:pharmacology; D058787:GABA-A Receptor Antagonists; D008297:Male; D008569:Memory Disorders / Q000188:drug therapy*; D051379:Mice; D008807:Mice, Inbred BALB C; D010852:Picrotoxin / Q000494:pharmacology; D017465:Receptors, Opioid, delta / Q000187:drug effects*
D001640:Bicuculline; D004743:Enkephalin, Leucine; D005442:Flumazenil; D058787:GABA-A Receptor Antagonists; D010852:Picrotoxin; D017465:Receptors, Opioid, delta