Animals ; Humans ; Learning ; drug effects ; Memory ; drug effects ; Metals ; toxicity ; Nervous System ; drug effects

Progress of studies concerning the protective effect of ginsenoside on central nerve system (CNS) in animals and its mechanism published in recent decade were reviewed in this paper. It showed that ginsenosides could improve the learning capacity and memory in normal, aged animals, as well as in model animals with impaired memory. The mechanism of the protective effect on CNS involves the effects on calcium channel blockade, glutamate and gamma-aminobutyric acid, antiperoxidation, estrogen-like action, nitric oxide and its synthase, also the inhibition on cerebral nerve cell apoptosis and amelioration on mitochondrial dysfunction, etc.
Aging ; drug effects ; Animals ; Avoidance Learning ; drug effects ; Ginsenosides ; pharmacology ; Memory ; drug effects ; Memory Disorders ; drug therapy ; Neuroprotective Agents ; pharmacology ; therapeutic use ; Nitric Oxide Synthase ; metabolism

In the present review, English literature on the pharmacological effects of Gastrodia elata was summarized. The literature mainly reported the effects of G. elata on central nervous system, including anticonvulsant, neuroprotection, improvement on learning and memory, and so on. These pharmacological effects were closely associated with its phenolic components.
Animals ; Central Nervous System ; drug effects ; Drugs, Chinese Herbal ; pharmacology ; Gastrodia ; chemistry ; Humans ; Memory ; drug effects

OBJECTIVETo investigate the effects of pentoxifylline on rats and mice with learning and memory dysfunctions.

METHODSMorris water maze test was used to observe the effects of pentoxifylline on learning and memory of naturally aging rats, and jumping stand test was performed to examine its effects in promoting the learning and memory functions in mice with scopolamine- and ethanol-induced memory dysfunctions.

RESULTSIn aging rats, pentoxifylline at high, moderate and low doses all significantly reduced the latency of platform finding in the place navigation test (P<0.01 or P<0.05 ), and increased the quadrant searching frequency in the spatial probe test (P<0.05). Pentoxifylline at the 3 doses significantly increased the latency of electrification (P<0.01 or P<0.05) and decreased the times of error (P<0.05) of the mice as compared with scopolamine- treated group. Pentoxifylline also improved ethanol-induced memory dysfunction in the mice, but the changes in the performance of the mice were not statistically significant.

CONCLUSIONPentoxifylline can improve the learning and memory abilities of rats and mice.

Aging ; Animals ; Behavior, Animal ; drug effects ; Ethanol ; Maze Learning ; drug effects ; Memory ; drug effects ; Memory Disorders ; chemically induced ; Mice ; Pentoxifylline ; pharmacology ; Rats ; Rats, Sprague-Dawley ; Scopolamine Hydrobromide

It is testified by long-standing traditional Chinese medicine clinical practice that ginseng was effective in treating dementia and promoting capability of learning and memory, for which ginsenoside Rg1 has been proved the main effective ingredient. Recently many researches have been carried out on the mechanism and action links of ginsenoside Rg1, and illustrated that it could exert the anti-dementia and nootropic effects through intervening multiple targets and links, thus to provide a theoretical basis for bettering the clinical use of ginsenoside Rg1.
Animals ; Ginsenosides ; pharmacology ; Humans ; Learning ; drug effects ; Memory ; drug effects ; Neuronal Plasticity ; drug effects ; Nootropic Agents ; pharmacology

In recent decades, scientists in Asian and Western countries have been paying great attention to ginseng research. Today, more than 200 ginsenosides and non-saponin constituents have been isolated and identified. Ginsenosides show biological activities only after being deglycosylated by intestinal bacteria. Aglycone protopanaxadiol and protopanaxatriol show the highest bioactivities. According to literature, the noticeable action of ginseng is that of delaying aging and especially increasing the nootropic effect, and it was found for the first time that Rg1 could increase hippocampal neurogenesis in vitro and in vivo under physiological and pathological circumstances. This is one of primary mechanisms underlying many of its pharmacological actions on the central nervous system. Rg1 was further shown to improve learning and memory in normal rats and mice. The nootropic signaling pathway has also been carried out in normal rats, and the Rg1-induced signaling pathway is similar to the memory formation that occurs in mammals, suggesting that Rg1 may have a potential effect in increasing intellectual capacity in normal people. Comparisons of chemical structures and pharmacologic functions between Panax ginseng and Panax quiquefolium were carried out by many scientists. The conclusion is that each has its own characteristics. There is no superiority or inferiority to the other.
Animals ; Cognition ; drug effects ; Ginsenosides ; pharmacology ; Humans ; Learning ; drug effects ; Memory ; drug effects ; Mice ; Neovascularization, Physiologic ; Neurogenesis ; Neuronal Plasticity ; drug effects ; Panax ; chemistry ; Rats ; Signal Transduction ; drug effects

Animals ; Brain Injuries ; drug therapy ; Gynostemma ; Learning ; drug effects ; Memory ; drug effects ; Phytotherapy ; Saponins ; pharmacology ; therapeutic use

AIM: To study the chemical constituents and their anti-amnesic effect from the hooks of Uncaria rhynchophylla. METHODS: The isolation of compounds was performed by chromatographic techniques and their structures were identified on the basis of spectral analysis. Their ameliorating effects on scopolamine-induced memory impairment in vivo using a Morris water-maze task and passive avoidance task system were evaluated. RESULTS: Activity-guided fractionation of the total extracts resulted in the isolation of four constituents, trans-anethole (1), p-anisaldehyde (2), estragole (3), and 3-oxo-olean-12-en-28-oic acid (4), which were found for the first time from this plant. CONCLUSION Compound 1 exhibited a better memory enhancing effect than tacrine, a positive agent, at the same dose in the passive avoidance test and a similar property in the water-maze test, and its action may be mediated, in part, by the acetylcholine enhancing cholinergic nervous system.
Animals ; Humans ; Male ; Memory ; drug effects ; Memory Disorders ; drug therapy ; Molecular Structure ; Plant Extracts ; administration & dosage ; chemistry ; isolation & purification ; Rats ; Rats, Sprague-Dawley ; Scopolamine ; adverse effects ; Uncaria ; chemistry

AIMTo study the effects of yi-zhi II (a compond of Chinese Traditional Medicine) on the alteration of synaptic structure in hippocampal CA3 and maintenance of memoy.

METHODSBy using the method of oral administration of yi-zhi II, the step-through test and electron microscopy, the latency of step-through and synaptic structure in hippocamal CA3 were tested.

RESULTS(1) The mice which had been given yi-zhi II prolong significantly the latency of step through (P < 0.05 or P < 0.01) on the 1st, 6th and 12th day after learning. (2) On the 6th and 12th day after learning, the length of synaptic active zone were markly improved in yi-zhi II and control, but that of yi-zhi II was better than that of control. (On the 6th day after learning, the number of perforated synapses and axo-dendrite synapses were significantly improved by the yi-zhi II (P < 0.05).

CONCLUSIONThe yi-zhi II could improve the learning and memory in mice. It migth improve the memory by increasing the length of synaptic active zone and the number of perforated synapses and axo-dendrite synapses in hippocampal CA3.

Animals ; Avoidance Learning ; drug effects ; CA3 Region, Hippocampal ; drug effects ; physiology ; Chromosome Pairing ; drug effects ; Drugs, Chinese Herbal ; pharmacology ; Male ; Memory ; drug effects ; Mice ; Neuroprotective Agents ; pharmacology

OBJECTIVETo investigate the relationship between the effects of zinc on hippocampal cholecystokinin (CCK) positive neurons and learning and memory ability of lead-exposed rats.

METHODSThirty-six Wistar rats were divided into control group, lead-exposed group (drunk 6.15 mmol/L of lead solution) and lead-zinc group (drunk 6.15 mmol/L of lead + 3.10 mmol/L of ZnSO(4) solution) randomly. Y-maze test was used to study learning and memory ability in rats; Atomic absorption method was used to determine serum and hippocampal lead content; ABC immunohistochemistry and quantitative graphic analysis were used to investigate the changes of CCK positive neurons in different hippocampal subfields in lead-exposed rats.

RESULTSThe learning and memory ability in lead-exposed rats were significantly lower (P < 0.05) while the serum and hippocampal lead content in lead-exposed rat were significantly higher (P < 0.05) than those in control and lead-zinc group. The number and optical density of CCK positive neurons in CA(1) and CA(3) areas of lead-exposed rats were significantly lower (P < 0.05) than those in control and lead-zinc group. No differences in these indexes between the control and lead-zinc group were found (P > 0.05).

CONCLUSIONLead may damage the learning and memory ability and affect the number of CCK positive neurons in lead-exposed rats. Zinc might play an important role in preventing lead-induced damages.

Animals ; Cholecystokinin ; metabolism ; Hippocampus ; drug effects ; metabolism ; Lead ; toxicity ; Maze Learning ; drug effects ; Memory ; drug effects ; Neurons ; drug effects ; metabolism ; Rats ; Rats, Wistar ; Zinc ; pharmacology