Jsou rozebrány mechanizmy LTP a LTD, jejich fyziologické působení a vliv na učení a paměť. Jsou rovněž popsány molekulárně biologické mechanizmy těchto dvou procesů. Je diskutována úloha hipokampu v procesu učení a paměti. Krátce jsou zmíněny i základní mechanizmy procesu učení a popsány různé typy paměti.

The mechanismus of LTP and LTD are discussed, their physiological effect especially on learning and memory is described. Also the molecular - biological mechanismus of these two processes are treated. The role hippocamus in the process of learning of memory is mentioned. Briefly are touched the basic mechanismus of learning and different types of memory are described.

• MeSH
• deprese patologie   MeSH
• farmakologie MeSH
• molekulární biologie MeSH
• neuroplasticita MeSH
• poruchy paměti MeSH
• synapse MeSH
• učení MeSH
• Publikační typ
• přehledy MeSH

Baclofen is the only clinically available metabotropic GABA(B) receptor agonist. In our experiment, we tested the hypothesis that long-term baclofen administration can impair learning and memory in rats. The experiment consisted of three parts. In the first part of the study the drug was administered simultaneously with the beginning of the behavioral tests. In the second and third part of the experiment baclofen was administered daily for 14 days and for one month before the tests. In each part of the experiment, adult rats were randomly divided into four treatment groups. Three groups were given an injection of baclofen at doses of 1 mg/kg, 5 mg/kg, 10 mg/kg, while the fourth group was injected with saline. The injections were given after each session. Spatial learning and memory were tested using the Morris water maze, involving three types of tests: Acquisition, Probe, and Re-acquisition. This work reveals that baclofen did not affect spatial learning at any of the tested doses and regardless of the length of administration. Memory was observed to be affected, but only at the highest dose of baclofen and only temporarily. This conclusion is in line with previously published clinical cases.

• MeSH
• agonisté receptorů GABA-B aplikace a dávkování   MeSH
• baklofen aplikace a dávkování   MeSH
• bludiště - učení účinky léků   fyziologie   MeSH
• krysa rodu rattus MeSH
• paměť účinky léků   fyziologie   MeSH
• potkani Wistar MeSH
• prostorové učení účinky léků   fyziologie   MeSH
• rozvrh dávkování léků MeSH
• vztah mezi dávkou a účinkem léčiva MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Inzulín je znám pro svůj periferní účinek na metabolizmus glukózy, tuků a bílkovin. Inzulín však hraje také významnou úlohu v mozku, kde funguje jako neuropeptid. Důkazy o tom, že inzulín je aktivním mozkovým hormonem, byly získány až v posledních letech 3- klinická data ukazují, že hraje významnou úlohu při fungování paměti. Působení inzulínu je realizováno přes inzulínové receptory, lokalizované zejména v bulbus olfactorius, v hypotalamu a hipokampu. Výsledky získané z experimentů na zvířatech ukazují na účinky inzulínu v mozku spojené s učením a pamětí. TaJcé kognitivní dysfunkce při demenci Alzheimerova typu AD) jsou spojeny s nedostatkem inzulínu v mozku a paměť u pacientů s AD se zlepšuje, když se hladina inzulínu zvýší.

Insulin is mainly known for its peripheral effects on the metabolism of glucose, fats, and proteins. However, insulin also exer ts impor- tant actions within the brain, and functions as a neuropeptide. Evidence for insulin being an active hormone in the brain has i ncreased greatly in recent years and some clinical data suggest that insulin plays an important role in memory performance. It acts via insulin receptors, localized predominantly in the olfactory bulbs, hypothalamus, and hippocampus. Data obtained in animal experiments r eveal an interesting insulin profile in the brain linked with learning and memory. Also cognitive dysfunctions in dementia of the Alz heimer type (AD) are associated with insulin deficiency in the brain, and memory improves in AD patients when insulin levels increase.

• MeSH
• Alzheimerova nemoc etiologie   komplikace   terapie   MeSH
• demence enzymologie   etiologie   komplikace   MeSH
• diabetes mellitus enzymologie   metabolismus   MeSH
• finanční podpora výzkumu jako téma MeSH
• inzulin metabolismus   nedostatek   terapeutické užití   MeSH
• lidé MeSH
• lithium terapeutické užití   MeSH
• poruchy paměti etiologie   komplikace   MeSH
• Check Tag
• lidé MeSH

Haloperidol je klasické neuroleptikum, které vyvolává motorické abnormity a poruchy učení. Cíl studie: Zhodnotit schopnost nootropik piracetamu, vinpocetinu a ginkgo biloba zlepšit prostorovou paměť myší léčených haloperidolem. Metodologie: Prostorová paměť byla hodnocena v Morrisově vodním bludišti (Morris water maze, MWM). Měřena byla účinnost piracetamu (50, 150 nebo 300 mg/kg i.p.), vinpocetinu (1, 2 nebo 4 mg/kg) nebo ginkgo biloba (25, 50 nebo 150 mg/kg) na pracovní paměť myší léčených haloperidolem (2 mg/kg, i.p.) podávaným k vyvolání kognitivní poruchy [25]. Léčivé látky byly buď podávány současně s haloperidolem, nebo 30 minut před podáním haloperidolu. Výsledky: Podání haloperidolu vedlo k významnému prodloužení latence při hledání ponořené plošiny. Piracetam podaný současně s haloperidolem nebo 30 min před antipsychotikem zkracoval v závislosti na dávce latenci při hledání ponořené plošiny. Vinpocetin podaný současně s haloperidolem kognitivní výkon nezlepšil, ale vinpocetin 4 mg/kg podaný 30 min před haloperidolem výrazně zkrátil latence při hledání ponořené plošiny. U myší léčených ginkgo biloba došlo ke zhoršení výkonu ve vodním bludišti. Závěr: Piracetam a vinpocetin, avšak nikoli ginkgo biloba, zlepšují poruchy učení a paměti vyvolané haloperidolem v Morrisově vodním bludišti. K potvrzení případné užitečnosti piracetamu a vinpocetinu při zlepšování kognice u pacientů léčených klasickými antipsychotiky je zapotřebí provést studie na lidských jedincích.

Haloperidol is a classic neuroleptic drug with the known drawback that it induces motor abnormalities and impaired learning. Aim: To investigate the nootropic drugs piracetam, vinpocetine and extract of Ginkgo biloba for their ability to improve spatial memory in mice treated with haloperidol. Methods: Spatial memory was assessed by means of the Morris water maze (MWM) test. The effects of piracetam (50, 150 or 300 mg/kg, i.p.), vinpocetine (1, 2 or 4 mg/kg) and Ginkgo biloba extract (25, 50 or 150 mg/kg) were studied on working memory in mice treated with haloperidol (2 mg/kg, i.p.) to induce cognitive impairment [25]. The drugs were either co-administered with haloperidol or given 30 min before haloperidol administration. Results: The administration of haloperidol resulted in a significant increase in the time taken to locate a submerged test platform (latency). The time taken to locate the submerged platform was reduced dose-dependently by piracetam co-administered with haloperidol or given 30 min prior to the antipsychotic drug. Vinpocetine co-administered with haloperidol failed to improve cognitive performance, but vinpocetine at 4 mg/kg administered 30 min before haloperidol markedly reduced the time to locate the submerged platform. Mice treated with Ginkgo biloba extract showed worsening of their performance on the water maze test. Conclusion: Piracetam and vinpocetine, but not Ginkgo biloba extract, alleviate haloperidol-induced impairment of learning and memory in the MWM test. Human studies are needed to establish whether piracetam as well as vinpocetine may prove of value in improving cognition in patients treated with classic antipsychotic drugs.

• Klíčová slova
• nootropika,
• MeSH
• antipsychotika škodlivé účinky   MeSH
• bludiště - učení účinky léků   MeSH
• experimenty na zvířatech MeSH
• farmakologie MeSH
• Ginkgo biloba MeSH
• haloperidol aplikace a dávkování   škodlivé účinky   MeSH
• myši MeSH
• neurologie MeSH
• piracetam terapeutické užití   MeSH
• poruchy paměti farmakoterapie   MeSH
• poruchy učení farmakoterapie   MeSH
• prostorová paměť MeSH
• statistika jako téma MeSH
• vinca alkaloidy terapeutické užití   MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• myši MeSH
• zvířata MeSH

Psychostimulants, including methamphetamine (MA), have neurotoxic effect, especially, if they are targeting CNS during its critical periods of development. The present study was aimed to examine cognitive changes after prenatal and neonatal MA treatment in combination with chronic MA exposure in adulthood of male rats. Eight groups of male rats were tested in adulthood: males whose mothers were exposed to MA (5 mg/kg) or saline (SA, 1 ml/kg) during the first half of gestation period (GD 1-11), the second half of gestation period (GD 12-22) and neonatal period (PD 1-11). In addition, we compared indirect neonatal application via the breast milk with the group of rat pups that received MA or SA directly by injection (PD 1-11). Males were tested in adulthood for cognitive changes in the Morris Water Maze (MWM). MWM experiment lasted for 12 days: Learning (Day 1-6), Probe test (Day 8) and Retrieval Memory test (Day 12). Each day of the MWM animals were injected with MA (1 mg/kg) or SA (1 ml/kg). Prenatal MA exposure did not induce changes in learning abilities of male rats, but neonatal exposure to MA leads to an increase search errors and latencies to find the hidden platform. Prenatal and also neonatal MA exposure impaired cognitive ability to remember the position of the platform in Retrieval Memory test in adulthood. Animals exposed to the prenatal treatment within the second half of gestation (ED 12-22) swam longer, slower and spent more time to find the hidden platform in Retrieval Memory test than animals exposed throughout other periods. The present study demonstrated that stage of development is crucial for determination the cognitive deficits induced by prenatal or neonatal MA exposure.

• MeSH
• bludiště - učení účinky léků   fyziologie   MeSH
• krysa rodu rattus MeSH
• methamfetamin aplikace a dávkování   toxicita   MeSH
• novorozená zvířata MeSH
• paměť účinky léků   fyziologie   MeSH
• potkani Wistar MeSH
• prostorové učení účinky léků   fyziologie   MeSH
• těhotenství MeSH
• věkové faktory MeSH
• zpožděný efekt prenatální expozice chemicky indukované   psychologie   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• mužské pohlaví MeSH
• těhotenství MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

A lot of studies have been concentrated on an effect of a short or a long-term administration of nicotine in humans or in animals. The negative effects on the human organism have been known for a long time, but these health problems are known especially from observing smokers. The number of tasks in human and in animals with accent on positive effect of nicotine has increased especially with regard to improvement of cognitive functions. The aim of this study was to investigate, how much a single dose of nicotine can influence the learning ability in rats. Male Wistar albino rats, 25-day-old, were studied. Two groups of animals received an intraperitoneal (i.p.) injection of nicotine in two different doses (0.75 mg/kg and 1.00 mg/kg b.w.). The third group received a single i.p. injection of saline in the equal volume (the control group). After the drug application the escape latency and the path length were measured and assessed in two periods of sessions in the Morris water maze. In our study no explicit changes of learning ability after a single nicotine injection was confirmed. Only at the third day of the task the trajectory was shorter (p<0.05) but this result appears too isolated. So we cannot exclude that such improvement was caused by other factors than by the nicotine administration.

• MeSH
• bludiště - učení účinky léků   MeSH
• krysa rodu rattus MeSH
• nikotin farmakologie   MeSH
• paměť účinky léků   MeSH
• potkani Wistar MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• práce podpořená grantem MeSH

Extremely low-frequency magnetic field (ELF-MF) has been suggested to influence the cognitive capability but this should be dynamically evaluated in a longitudinal study. Previous training can affect performance, but the influence under magnetic field is unclear. This study aims to evaluate the effects of previous training and ELF-MF exposure on learning and memory using the Morris water maze (MWM). Sprague-Dawley rats were subjected to MWM training, ELF-MF exposure (50 Hz, 100 microT), or ELF-MF exposure combined with MWM training for 90 days. Normal rats were used as controls. The MWM was used to test. The data show that the rats exposed to training and ELF-MF with training performed better on spatial acquisition when re-tested. However, during the probe trial the rats showed no change between the training phase and the test phase. Compared with the control group, the ELF-MF group showed no significant differences. These results confirm that previous training can improve the learning and memory capabilities regarding spatial acquisition in the MWM and this effect can last for at least 90 days. However, this improvement in learning and memory capabilities was not observed during the probe trial. Furthermore, ELF-MF exposure did not interfere with the improvement in learning and memory capabilities.

• MeSH
• bludiště - učení * MeSH
• magnetické pole * MeSH
• potkani Sprague-Dawley MeSH
• prostorová paměť * MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Neural components enabling flexible cognition and behavior are well-established, and depend mostly on proper intercommunication within the prefrontal cortex (PFC) and striatum. However, dense projections from the ventral hippocampus (vHPC) alter the functioning of the medial PFC (mPFC). Dysfunctional hippocampo-prefrontal connectivity negatively affects the integrity of flexible cognition, especially in patients with schizophrenia. In this study, we aimed to test the role of the vHPC and mPFC in a place avoidance task on a rotating arena using two spatial flexibility task variants - reversal learning and set-shifting. To achieve this, we inactivated each of these structures in adult male Long-Evans rats by performing bilateral local muscimol (a GABAA receptor agonist) injections. A significantly disrupted performance was observed in reversal learning in the vHPC-inactivated, but not in the mPFC-inactivated rats. These results confirm the notion that the vHPC participates in some forms of behavioral flexibility, especially when spatial cues are needed. It seems, rather unexpectedly, that the mPFC is not taxed in these flexibility tasks on a rotating arena.

• MeSH
• agonisté receptorů GABA-A farmakologie   MeSH
• hipokampus účinky léků   fyziologie   MeSH
• krysa rodu rattus MeSH
• muscimol farmakologie   MeSH
• pozornost účinky léků   fyziologie   MeSH
• prefrontální mozková kůra účinky léků   fyziologie   MeSH
• prostorové vidění účinky léků   fyziologie   MeSH
• reverzní učení účinky léků   fyziologie   MeSH
• učení vyhýbat se účinky léků   fyziologie   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Neural components enabling flexible cognition and behavior are well-established, and depend mostly on proper intercommunication within the prefrontal cortex (PFC) and striatum. However, dense projections from the ventral hippocampus (vHPC) alter the functioning of the medial PFC (mPFC). Dysfunctional hippocampo-prefrontal connectivity negatively affects the integrity of flexible cognition, especially in patients with schizophrenia. In this study, we aimed to test the role of the vHPC and mPFC in a place avoidance task on a rotating arena using two spatial flexibility task variants - reversal learning and set-shifting. To achieve this, we inactivated each of these structures in adult male Long-Evans rats by performing bilateral local muscimol (a GABAA receptor agonist) injections. A significantly disrupted performance was observed in reversal learning in the vHPC-inactivated, but not in the mPFC-inactivated rats. These results confirm the notion that the vHPC participates in some forms of behavioral flexibility, especially when spatial cues are needed. It seems, rather unexpectedly, that the mPFC is not taxed in these flexibility tasks on a rotating arena.

• MeSH
• agonisté receptorů GABA-A farmakologie   MeSH
• hipokampus účinky léků   fyziologie   MeSH
• krysa rodu rattus MeSH
• muscimol farmakologie   MeSH
• pozornost účinky léků   fyziologie   MeSH
• prefrontální mozková kůra účinky léků   fyziologie   MeSH
• prostorové vidění účinky léků   fyziologie   MeSH
• reverzní učení účinky léků   fyziologie   MeSH
• učení vyhýbat se účinky léků   fyziologie   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Spatial navigation comprises a widely-studied complex of animal behaviors. Its study offers many methodological advantages over other approaches, enabling assessment of a variety of experimental questions and the possibility to compare the results across different species. Spatial navigation in laboratory animals is often considered a model of higher human cognitive functions including declarative memory. Almost fifteen years ago, a novel dry-arena task for rodents was designed in our laboratory, originally named the place avoidance task, and later a modification of this approach was established and called active place avoidance task. It employs a continuously rotating arena, upon which animals are trained to avoid a stable sector defined according to room-frame coordinates. This review describes the development of the place avoidance tasks, evaluates the cognitive processes associated with performance and explores the application of place avoidance in the testing of spatial learning after neuropharmacological, lesion and other experimental manipulations.

• MeSH
• behaviorální výzkum metody   MeSH
• chování zvířat fyziologie   MeSH
• druhová specificita MeSH
• kognice fyziologie   MeSH
• modely u zvířat MeSH
• neurovědy metody   MeSH
• paměť fyziologie   MeSH
• prostorové chování fyziologie   MeSH
• učení vyhýbat se fyziologie   MeSH
• vnímání prostoru fyziologie   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH