Cockroaches (Periplaneta americana) learned to passively avoid electric shock in a two-compartment box after a single training trial. However, Ss exposed to CO2 gas immediately after the training trial failed to show retention of the previous experience when tested 24 h later. Results obtained are consistent with those observed in studies of retrograde amnesia in vertebrates. Article: Numerous ...

These experiments examined the effects, on retention, of posttraining intra-amygdala administration of norepinephrine (NE), and propranolol. Rats were trained on a one-trial step-through inhibitory avoidance task and tested for retention 24 h later. Injections were administered bilaterally (1.0 microliter/injection) through chronically-implanted cannulae. Low doses of NE (0.1 or 0.3 microgram) ...

Intra-amygdala infusion of the non-N-methyl-D-aspartate (NMDA) receptor antagonist 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX) prior to testing impairs inhibitory avoidance retention test performance. Increased training attenuates the impairing effects of amygdala lesions and intra-amygdala infusions of CNQX. The objective of the present study was to determine the effects of additional training...

introduction: exposure to 3, 4- methylenedioxymethamphetamine (mdma) could lead to serotonergic system toxicity in the brain. this system is responsible for learning and memory functions. studies show that mdma causes memory impairment dose-dependently and acutely. the present study was designed to evaluate the chronic and acute effects of mdmd on spatial memory and acquisition of passive avoid...

‎ Introduction: Controversial results have been reported about the effect of morphine and stress on learning and spatial memory in rodents. There are very few studies about the effects of ultra low doses of morphine on memory. In this study, effects of acute administration of low and usual doses of morphine on memory formation and retention in the presence and absence of repeated stress w...

OBJECTIVES Calcineurin (CN) is a main phosphatase and a critical regulator of cellular pathways for learning, memory, and plasticity. The FK-506 (tacrolimus), a phosphatase inhibitor, is a fungal-derived agent and a common immune suppressant extensively used for tissue transplantation. To further clarify the role of CN in different stages of learning and memory the main aim of this study was to...

The memory effects of agonists and antagonists of some serotonin (5-HT) receptor subtypes were examined in experiments on rats using an active avoidance method (shuttle-box). The 5-HT receptor antagonists NAN 190 (1 mg/kg i.p.) and pindolol (6 mg/kg i.p.) improved some indices for memory; the 5-HT2 and 5-HT3 receptor antagonists ritanserin (1 mg/kg i.p.) and ondansetron (0.1 mg/kg i.p.) exerted...

Certain experimental procedures in learning and memory research require that the animal be anesthetized soon after the acquisition session. Volatile anesthetics, such as isoflurane, are good candidates for this purpose because they have both a rapid onset of effect and a quick awakening of the animal when anesthesia is discontinued. However, memory consolidation might be affected by a mixed eff...