Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0002622 (amnesia)
 5,520 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Pharmacological analysis was used for studying the influence of 24-hour deprivation of paradoxical sleep by Jouvet method on retention of conditioned reaction of passive avoidance in rats. Psychotropic substances of different action were used for the analysis: nootropes as anti-amnestic--pyracetam (400 mg/kg), kleregil (100 mg/kg), centrofenoxin (50 mg/kg) and watersoluble salt of 3-oxypiridin derivative (3-OP) (50 mg/kg) and tranquilizer of bensodiazepine series phenazepam (1 mg/kg) as antistress and antiphobic. It was established that 24-hour deprivation disturbed the elaborated reaction but did not change the rate of emotionality and orienting-investigating behaviour of rats in the open field. Nootropes effectively restored the conditioned passive avoidance reaction while phenazepam had no effect. This allows to suggest that Jouvet method of paradoxical sleep deprivation elicits amnesia and its cause is not only stress but deficit of paradoxical sleep.
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PMID:[Effect of drugs of the nootropic class on rat behavior after deprivation of the paradoxical stage of sleep]. 309 98

The acquisition of a passive avoidance conditioned response was disrupted in the rat by electroconvulsive shock (ECS) and scopolamine administration. D,L-pyroglutamic acid (D,L-PCA) 500 and 1000 mg/kg, administered as arginine salt 120 min before the retest, prevented both the ECS and scopolamine-induced amnesia. Arginine alone was ineffective. Scopolamine brought about a 52 and 39% decrease, respectively, in cortical and hippocampal acetylcholine (ACh) levels, measured by means of a gas-chromatographic method. D,L-PCA 500 and 1000 mg/kg also prevented the decrease in brain ACh level. When the two isomers were studied separately, D-PCA was more effective than L-PCA and antagonized scopolamine-induced amnesia at the doses of 250 and 500 mg/kg. In conclusion, D,L-PCA is active on cortical and hippocampal cholinergic mechanisms and, like other 2-oxopyrrolidone derivatives, shows cognition-enhancing properties.
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PMID:Effect of pyroglutamic acid stereoisomers on ECS and scopolamine-induced memory disruption and brain acetylcholine levels in the rat. 344 11

The effects of trans-(+/-)-3,4-dichloro-N-methyl-N-(2-[1-pyrrolidinyl] cyclohexyl) benzeneacetamide methanesulfonate salt (U-50488H) on carbon monoxide (CO)-induced amnesia in mice were investigated using spontaneous alternation and step-down type passive avoidance tasks. The lower percentage alternation and shorter median step-down latency in the retention test of the CO-exposed group indicated that memory deficiency occurred in mice when behavioral testing commenced 5-7 days after CO exposure. Administration of U-50488H (0.21 and 0.64 mumol/kg s.c.) 25 min before spontaneous alternation performance or the first training session of the passive avoidance task improved the CO-induced impairment of alternation performance and passive avoidance tasks. To determine whether the effect of U-50488H was mediated via kappa-opioid receptors, we attempted to block its action using a selective kappa-opioid receptor antagonist (nor-binaltorphimine). Nor-binaltorphimine (5.44 nmol/mouse i.c.v.) blocked the effect of U-50488H on CO-induced delayed amnesia. Furthermore, a low dose of scopolamine (0.41 mumol/kg s.c.) also blocked the ameliorating effect of U-50488H. U-50488H (0.21-2.15 mumol/kg s.c.) did not facilitate the acquisition of memory in normal mice. These results suggest that U-50488H modulates the kappa-opioid receptor-mediated opioid neuronal system and activates the cholinergic neuronal system, and that it ameliorates the disruptive effect of CO on acquisition and/or consolidation of memory.
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PMID:U-50488H, a selective kappa-opioid receptor agonist, improves carbon monoxide-induced delayed amnesia in mice. 896 Aug 74

Effects of a Hypericum extract in therapeutic use and hyperforin sodium salt were evaluated in rat and mouse avoidance tests. In a conditioned avoidance response (CAR) test on the rat, oral daily administration of hyperforin (1.25 mg/kg/day) or of the extract (50 mg/kg/day) before the training sessions considerably improved learning ability from the second day onwards until the day 7. In addition, the memory of the learned responses acquired during 7 consecutive days of administration and training was largely retained even after 9 days without further treatment or training. The observations made using different doses indicate that these learning-facilitating and/or memory-consolidating effects by the agents follow inverse U-shaped dose-response curves in dose ranges lower than (for hyperforin) or equal to (for Hypericum extract) their effective dose in the behavioral despair test for antidepressants. In a passive avoidance response test on the mouse, a single oral dose (1.25 mg/kg) of hyperforin not only improved memory acquisition and consolidation, but also almost completely reversed scopolamine-induced amnesia. The single Hypericum extract dose tested (25 mg/kg) did not reveal any significant effects in the passive avoidance response (PAR) test on the mouse. These observations suggest that the Hypericum extract could be a novel type of antidepressant with memory enhancing properties, and indicate that hyperforin is involved in its cognitive effects. Pure hyperforin seems to be a more potent antidementia agent than an antidepressant.
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PMID:Hypericum extract and hyperforin: memory-enhancing properties in rodents. 1151 79

The present study was aimed to investigate the cognitive enhancing and anti-oxidant activities of Inonotus obliquus (Chaga) against scopolamine-induced experimental amnesia. Methanolic extract of Chaga (MEC) at 50 and 100 mg kg (-1)doses were administered orally for 7 days to amnesic mice. Learning and memory was assessed by passive avoidance task (PAT) and Morris water maze (MWM) test. Tacrine (THA, 10 mg kg (-1), orally (p.o)) used as a reference drug. To elucidate the mechanism of the cognitive enhancing activity of MEC, the activities of acetylcholinesterase (AChE), anti-oxidant enzymes, the levels of acetylcholine (ACh) and nitrite of mice brain homogenates were evaluated. MEC treatment for 7 days significantly improved the learning and memory as measured by PAT and MWM paradigms. Further, MEC significantly reduced the oxidative-nitritive stress, as evidenced by a decrease in malondialdehyde and nitrite levels and restored the glutathione and superoxide dismutase levels in a dose dependent manner. In addition, MEC treatment significantly decreased the AChE activity in both the salt and detergent-soluble fraction of brain homogenates. Further, treatment with MEC restored the levels of ACh as did THA. Thus, the significant cognitive enhancement observed in mice after MEC administration is closely related to higher brain anti-oxidant properties and inhibition of AChE activity. These findings stress the critical impact of Chaga, a medicinal mushroom, on the higher brain functions like learning and memory.
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PMID:Amelioration of scopolamine induced cognitive dysfunction and oxidative stress by Inonotus obliquus - a medicinal mushroom. 2177 70