Oxiracetam Research Articles

Exploring the effects of moxibustion on cognitive function in rats with multiple cerebral infarctions from the perspective of glial vascular unit repairing.

This study aimed to explore the effect of moxibustion at Governor Vessel (GV) acupoints, including Baihui (GV 20), Shenting (GV 24) and Dazhui (GV 14) for 14days on glial vascular unit (GVU) in rats with multiple microinfarctions (MMI), and to explore its action mechanism. The effect and mechanism of moxibustion on vascular dementia (VD) were studied in MMI rats by means of behavioral and molecular biology experiments. Rats receiving MMI showed impairment of memory function, reduction of cerebral blood flow, damage of blood-brain barrier (BBB) integrity and increased brain mass. MMI also increased neuronal degeneration in the hippocampus. Notably, levels of glial fibrillary acidic protein (GFAP) and complement component 3 significantly increased, but those of Connexin43 (CX43) and platelet derived growth factor receptor β (PDGFRβ) significantly decreased in the hippocampus of the rats receiving MMI. Moxibustion, as well as oxiracetam (ORC) treatment improved memory function and neuronal degeneration, ameliorated BBB integrity, increased cerebral blood flow and decreased brain mass. In addition, moxibustion as well as oxiracetam (ORC) treatment reduced the decrease of CX43 protein and increased PDGFRβ protein level in the hippocampus of MMI rats. Moreover, moxibustion treatment reversed MMI-induced increase of the GFAP/CX43 ratio in vascular structural units. Importantly, after PDGFRβ inhibition, VD rats treated with moxibustion had impaired learning and memory, decreased cerebral blood flow, and BBB disruption. Moxibustion treatment at various GV acupoints improved cerebral blood flow and repaired BBB function in rats with MMI, likely through protecting GVU.

Efficacy and association of hyperbaric oxygen therapy combined with butylphthalide and oxiracetam with serum levels of inflammatory markers in vascular cognitive impairment after acute ischemic stroke.

This study evaluated the efficacy of hyperbaric oxygen therapy (HBOT) combined with butylphthalide (NBP) and oxiracetam (OXR) for vascular cognitive impairment after acute ischemic stroke and investigated the association between such combination therapy and the serum levels of inflammatory markers. This was a prospective study which included eighty patients with post-AIS cognitive impairment (PAISCI) treated in Dongguan City People's Hospital from January 2020 to January 2022. They were randomized into study group and control group. The control group was provided with conventional therapy consisting of NBP for intravenous transfusion and oral OXR, while the study group received combination therapy of HBOT, NBP, and OXR. A comparison was drawn between the two groups regarding clinical outcomes, levels of recovery of cognitive and neurological function and intelligence, changes in inflammatory markers, and incidence of adverse drug reactions (ADRs). The response rate of the study group was significantly higher than that of the control group (p=0.04). The cognitive function scores of the study group were significantly better than those of the control group at the end of treatment (p<0.05). The post-treatment levels of inflammatory markers were significantly reduced in the study group when compared with the control group (p<0.05). At two weeks after treatment, the ADR rate of study group was significantly lower than the control group (p=0.03). The combination therapy of HBOT, NBP, and OXR demonstrates robust efficacy in patients with PAISCI. It is deemed to be a safe and effective treatment regimen.

Pharmacokinetic Properties of S-oxiracetam After Single and Multiple Intravenous Infusions in Healthy Volunteers.

As a chiral drug, oxiracetam (ORT) can exist in two different isomeric forms: S-oxiracetam (S-ORT) and R-oxiracetam (R-ORT). S-ORT has emerged as a promising nootropic drug with the potential to treat brain injury and the resulting loss of neural function, memory and mental impairment as assessed by studies in various animal models. However, limited data are available on the pharmacokinetics of S-ORT in humans, so the present study was designed to evaluate the safety and pharmacokinetic profile of S-ORT in healthy volunteers. In part 1, subjects were intravenously administered single ascending dose (2.0, 4.0 and 8.0 g) S-ORT. In part 2, subjects were treated at a single intravenous infusion dose of 3.0 g S-ORT or 6.0 g racemic ORT using a two-sequence, two-period crossover design. In part 3, subjects were intravenously injected with 4.0 g S-ORT once a day for 7 days. Blood and urine samples were collected to evaluate the pharmacokinetic parameters and urine excretion rate. The safety profile of the drug was also evaluated throughout the study. Fifty-two subjects (30 in part 1, 12 in part 2, 10 in part 3) completed the study; only one subject displayed a mild adverse event, which possibly was treatment related, and no serious adverse event occurred. In part 1 for a single dose of 2.0, 4.0 and 8.0 g, the maximum concentration (Cmax) values were 111.28±18.99, 230.76±29.16 and 352.67±42.94 μg/ml, respectively; the values of area under the plasma concentration-time curve (AUC) from time zero to the time of last quantifiable concentration (AUC0-t) were 267.09±59.66, 524.50 ±72.87 and 822.68±95.21 μg·h/ml, respectively; the AUC from 0 h to infinity (AUC0-∞) values were 274.72±61.65, 536.06±78.13 and 832.07±96.91 μg·h/ml, respectively. The urine excretion rate of the unchanged drug was approximately 60%. After consecutive administration of S-ORT for 7 days, the accumulation index was 1.05±0.08. The plasma drug concentration-time curves for both S-ORT and R-oxiracetam (R-ORT) were almost identical. S-ORT was well tolerated, and no serious adverse events occurred in 2.0, 4.0 and 8.0 g in single- and 4.0 g in multiple-dose studies. S-ORT showed dose linearity with increasing doses and no drug accumulation after 7 days of continuous administration was observed.

Poria cocos polysaccharide attenuates damage of nervus in Alzheimer's disease rat model induced by D-galactose and aluminum trichloride.

Poria cocos polysaccharide (PCP) is a compound from Poria cocos, and which is used as a classical tonic agent. This article aims to investigate the effects of PCP on neuronal damage of hippocampus and cognitive function in a rat model of Alzheimer's disease induced by D-galactose and aluminum trichloride. Oxiracetam (ORC) was used as a positive drug in this experiment. The rats were treated with PCP at doses of 100, 200 and 300 mg/kg/day for 30 days and ORC at dose of 346 mg/kg/day after modeling. The results of behavioral test showed that PCP could prevent cognitive decline in Alzheimer's disease rats as assessed by Y-maze test and Morris water maze test. Results of hippocampus slices showed that neurons were integrated and regularly arranged in the groups, which were administered along with PCP. Moreover, PCP could reduce neuronal apoptosis in hippocampus of Alzheimer's disease rats. Furthermore, the activities of superoxide dismutase in the hippocampus were elevated by PCP administration, while acetyl cholinesterase, reactive oxygen, malondialdehyde and inflammatory factors levels were reduced. In addition, we found PCP could attenuate MAPK/NF-κB signal pathway in the hippocampus. All results illustrated that PCP could exert neuroprotective effects at least partly through alleviating oxidative stress, apoptosis, inflammation and inhibiting the MAPK/NF-κB pathway in Alzheimer's disease rats induced by D-galactose and aluminum trichloride.

Oxiracetam Mediates Neuroprotection Through the Regulation of Microglia Under Hypoxia-Ischemia Neonatal Brain Injury in Mice.

In neonatal hypoxic-ischemic brain damage (HIBD), in addition to damage caused by hypoxia and ischemia, over-activation of inflammation leads to further deterioration of the condition, thus greatly shortening the optimal treatment time window. Ischemic penumbra, the edematous area encompassing the infarct core, is characterized by typical activation of microglia and overt inflammation, and prone to incorporate into the infarct core gradually after ischemia onset. If treated in time, the cells located in the penumbra can survive, thereby impeding the expansion of the infarction. We demonstrated for the first time that in the acute phase of HIBD in neonatal mice, treatment of Oxiracetam (ORC) significantly curtailed the size of ischemic penumbra together with drastic reduction of infarction. By staining various cellular markers, we found that the penumbra was defined and concentrated with activated microglia. We also analyzed transmission electron microscopy and Luminex assay results to elucidate the mechanisms involved. We further confirmed that ORC switched polarization of microglia from the inflammatory towards the alternatively activated phenotype, thus promoting microglia from being neurotoxic into neuroprotective. Meanwhile, ORC decreased proliferation of microglia; however, their functions of phagocytosis and autophagy were otherwise enhanced. Last, we clarified that ORC promoted autophagy through the AMPK/mTOR pathway, which further induced the transition of the inflammatory to the alternatively activated phenotype in microglia. The pro-inflammatory factors secretion was inhibited as well, thereby reducing the progression of the infarction. Taken together, it is concluded that Oxiracetam reduced the expansion of ischemic infarction in part via regulating the interplay between microglia activation and autophagy, which would delay the progression of HIBD and effectively prolong the time window for the clinical treatment of HIBD.

Oxiracetam Offers Neuroprotection by Reducing Amyloid β-Induced Microglial Activation and Inflammation in Alzheimer's Disease

Background: Alzheimer's disease (AD) is characterized by amyloid beta (Aβ) accumulation in the brain, which triggers the activation of microglia; in turn, microglia release neuroinflammatory factors capable of damaging neurons. Thus, a therapeutic approach targeting this sustained microglia-induced inflammatory response deserves investigation. Here, we examined whether oxiracetam (ORC), a nootropic of the racetam family, can indirectly prevent Aβ-induced neurotoxicity by attenuating microglial activation.Methods: Aβ42 oligomers were used to stimulate BV2 microglial cells, and the morphological changes and phagocytic capacity of BV2 cells were evaluated using fluorescence microscopy. We used quantitative reverse transcription polymerase chain reaction to assess the inhibitory effects of ORC on Aβ-induced mRNA levels of interleukin-1β (IL-1β), IL-6, and tumor necrosis factor-α (TNF-α); enzyme-linked immunosorbent assay was used to examine the productions of these cytokines. We also assessed the mRNA level of inducible nitric oxide synthase and the production of nitric oxide (NO). The conditioned medium from BV2 cells was used to culture hippocampal HT22 cells to assess indirect toxicity using the MTT assay.Results: ORC prevented the Aβ-induced activation of BV2 cells, as reflected by reduced morphological changes and phagocytic ability. In addition, ORC downregulated the expression of Aβ-induced cytokines (IL-1β, IL-6, and TNF-α) and the production of NO in BV2 cells. Furthermore, ORC protected HT22 cells from indirect damage evoked by Aβ-treated BV2 cell-conditioned medium, but not from direct Aβ-induced toxicity.Conclusions: ORC suppressed the activation of BV2 cells, decreased the production of Aβ-induced inflammatory molecules and NO in BV2 cells, and protected HT22 cells against indirect toxicity mediated by Aβ-treated BV2 cell-conditioned medium. Thus, ORC may exert a protective role in AD through attenuating the damage caused by inflammation and oxidative stress.

Comparative toxicity and toxicokinetic studies of oxiracetam and (S)-oxiracetam in dogs

Oxiracetam (ORT) is known as a derivative of piracetam in the family of nootropics for treating memory impairment and cognition disorders.Given the chiral toxicological concerns surrounding ORT and the absence studies of (S)-ORT, the toxicity and toxicokinetics of (S)-ORT, and comparative toxicology of oxiracetam were systematically investigated in dogs following acute and 13-week repeated oral dosing.The animal toxicity mainly manifested as loose stools in both the acute and the 13-week studies. The no-observed-adverse-effect level is proposed to be 100 mg/kg. The 13-week toxicokinetics study indicated that, in the (S)-ORT group, the time to peak concentration was delayed, elimination half-life extended, and apparent volume of distribution increased compared with the ORT group. The clearance rate increased at low- and mid-doses, but decreased in the high-dose group and was accompanied by drug accumulation. Compared with the same dose of ORT, (S)-ORT had a lower clearance rate and longer elimination half-life.

Oxiracetam ameliorates cognitive deficits in vascular dementia rats by regulating the expression of neuronal apoptosis/autophagy-related genes associated with the activation of the Akt/mTOR signaling pathway.

Oxiracetam (ORC) is a commonly used nootropic drug for improving cognition and memory impairments. The therapeutic effect and underlying mechanism of ORC in vascular dementia (VaD) treatment remain unknown. In this study, 3-month-old male Sprague-Dawley rats with permanent bilateral common carotid artery occlusion-induced VaD were treated orally with low (100 mg/kg) or high (200 mg/kg) dose ORC once a day for 4 weeks. The results of the Morris water maze test and Nissl staining showed that ORC treatment significantly alleviated learning and memory deficits and neuronal damage in rats with VaD. Mechanistically, the protein levels of a panel of genes associated with neuronal apoptosis (Bcl-2, Bax) and autophagy (microtubule-associated protein 1 chain 3, Beclin1, p62) were significantly altered by ORC treatment compared with VaD, suggesting a protective role of ORC against VaD-induced neuronal apoptosis and autophagy. Moreover, the Akt/mTOR pathway, which is known to be the upstream signaling governing apoptosis and autophagy, was found to be activated in ORC-treated rats, suggesting an involvement of Akt/mTOR activation in ORC-rendered protection in VaD rats. Taken together, this study demonstrated that ORC may alleviate learning and memory impairments and neuronal damage in VaD rats by altering the expression of apoptosis/autophagy-related genes and activation of the Akt/mTOR signaling pathway in neurons.

The fluorescence and resonance Rayleigh scattering spectra study on the interactions of palladium (II)-Nootropic chelate with Congo red and their analytical applications

A highly sensitive detection approach of resonance Rayleigh scattering spectra (RRS) is firstly applied to analyzing nootropic drugs including piracetam (PIR) and oxiracetam (OXI). In HCl-NaAc buffer solution (pH=3.0), the OXI chelated with palladium (II) to form the chelate cation [Pd2·OXI]2+, and then reacted with Congo red (CGR) by virtue of electrostatic attraction and hydrophobic force to form binary complex [Pd2·OXI]. CGR2, which could result in the great enhancement of RRS. The resonance Rayleigh scattering signal was recorded at λex=λem=375nm. This mixture complex not only has higher RRS, but also makes contribution to significant increase of fluorescence, and the same phenomena also were discovered in PIR. The enhanced RRS intensity is in proportion to the PIR and OXI concentration in the range of 0.03–3.0μgmL−1, and the detection limit (DL) of RRS method for PIR and OXI is 2.3ngmL−1 and 9.7ngmL−1. In addition, the DL of fluorescence method for PIR and OXI is 8.4μgmL−1 and 19.5μgmL−1. Obviously, the RRS is the highly sensitive method, and the recoveries of the two kinds of nootropic drugs were range from 100.4% to 101.8.0% with RSD (n=5) from 1.1% to 3.1% by RRS method. This paper not only investigated the optimum conditions for detecting nootropics with using RRS method, but also focused on the reasons for enhancing RRS intensity and the reaction mechanism, which in order to firm and contract the resultant. Finally, The RRS method has been applied to detect nootropic drugs in human urine samples with satisfactory results.

Comparative pharmacokinetic studies of racemic oxiracetam and its pure enantiomers after oral administration in rats by a stereoselective HPLC method

Oxiracetam (ORC), a nootropic drug used for improving the cognition and memory, has an asymmetric carbon in its structure and exists as (S)- and (R)-ORC. The pharmacokinetic profiles of racemic oxiracetam and its pure enantiomers in rats were evaluated and compared by enantioselective high-performance liquid chromatography, which was performed on a Chiralpak ID column with a mobile phase of hexane–ethanol–trifluoroacetic acid (78:22:0.1, v/v/v). The method was validated with respect to selectivity, linearity, accuracy and precision, stability and the limit of quantification. The validation acceptance criteria were met in all cases. A saturating phenomenon of (S)-ORC was observed when the dosage ranged from 200mg/kg to 800mg/kg. The two enantiomers showed similar profiles in the absorb phase, and reached the maximum concentration at 2h after oral administration. However, compared with the racemate group, the AUC/dose and Cmax/dose ratios of (S)-ORC were higher and Cl/f was lower in enanpure (S)-ORC group. The Cmax of (S)-ORC decreased from 21.3±5.0μg/ml to 13.2±4.2 when (R)-ORC was co-administrated at the dose of 200mg/kg. AUC0–t values of (S)-ORC were different after oral administration of 200mg/kg (S)-ORC and 400mg/kg racemic ORC (96.7±15.5 and 50.1±16.3μgh/ml). The higher absorption and slower elimination suggest that enantiopure (S)-ORC could be a promising drug that efficiently reduces clinical dosage, improves therapeutic indices, decreases toxicology risks, and results in increased therapeutic ration.

Impact of Shuxuetong combined with oxiracetam on NIHSS and MMSE scores of patients with cerebral hemorrhage

Objective To study and analyze the impact of Shuxuetong combined with oxiracetam on the NIHSS and MMSE scores of patients with cerebral hemorrhage,and to explore the efficacy of the treatment.Methods 98 patients with cerebral hemorrhage were chosen from our hospital from April,2012 to April,2013 and were randomly divided into an observation group and a control group,49 cases for each group.All patients received regular medication,such as fructose,mannitol,and glycerol symptomatic treatment and rehabilitation training.In addition,the control group were treated with citicoline sodium,and the observation group with Shuxuetong and oxiracetam.Three weeks after the treatment,the NIHSS and MMSE scores,the hematoma volume,the surrounding low-density district condition,and adverse reactions were compared between the two groups.Results The NIHSS and MMSE scores were (2.23 ± 1.96) and (27.08 ± 6.12) 3 weeks after the treatment and were (7.15 ± 4.68) and (16.32 ± 5.40) before the treatment in the observation group and were (3.91 ± 2.87) and (21.76 ± 5.95) 3 weeks after the treatment in the control group,respectively,with statistical differences (P ＜ 0.05).After the treatment,the hematoma volume and the range of surrounding lowdensity district declined in both groups,but declined more in the observation group than in the control group,with statistical differences (P ＜ 0.05).There were no statistical differences in adverse reactions between the two groups (P ＞ 0.05).Conclusions Shuxuetong combined with oxiracetam in the treatment of cerebral hemorrhage has significant effect,can significantly improve the neurological symptoms,and is worth being clinically recommended. Key words: Shuxuetong; Oxiracetam; Cerebral hemorrhage; NIHSS; MMSE

Development and validation of a RP-HPLC method for the simultaneous determination of aceglutamide and oxiracetam in an injection formulation.

This paper describes a rapid method to determine aceglutamide (ACE) and oxiracetam (OXI) present in an injection formulation using reversed-phase high-performance liquid chromatography. The method was validated with respect to suitability, linearity, accuracy, precision and robustness. Chromatography was carried out on an Elite SinoChrom ODS-BP C18 (5 μm, 250 × 4.60 mm) column with an isocratic mobile phase composed of methanol-phosphate buffer (pH 3.0) in the ratio of 5:95, v/v, at a flow rate of 1.0 mL/min. Detection was carried out using a UV-PDA detector at 210 nm. The linearity range for ACE and OXI were 10-500 and 10-300 μg/mL, respectively. The relative standard deviations for replicate measurements were always <2%.

Effects of β-aescine sodium plus oxiracetam on plasma homocysteine and MCP-1 protein in patients with acute cerebral infarction

Objective To study the effects of β-aescine sodium plus oxiracetam on plasma homocysteine (Hcy) and monocyte chemotactic factor(MCP-1) protein in patients with acute cerebral infarction.Methods 117 patients with acute cerebral infarction were randomly divided into the two groups,the observation group (n =60 cases) and the control group (n =57 cases).The patients in the control group were treated with the conventional treatment,while the patients in the observation group were treated with joint treatment ofβ-aescine sodium plus oxiracetam.They were treated for 14 days.Plasma Hcy and MCP-1 were detected.Results The total efficicies were 95.0％ in the observation group and 84.5％ in the control group.There was a significant difference between two groups (x2 =5.801,P ＜0.05).Plasma Hcy and MCP-1 were decreased after treatment (t =9.551,4.296,2.001,21.070,P ＜ 0.05,P ＜0.01).Plasma Hcy and MCP-1 in the observation group were lower than these in the control group (t =4.997,25.276,all P ＜ 0.05).Conclusion β-aescine sodium plus oxiracetam can decrease plasma Hcy and MCP-1 in patients with acute cerebral infarction. Key words: Cerebral infarction; Oxiracetam; β-aescine sodium; Homocysteine; Monocyte chemotactic factor

The influence of oxiracetam plus mNGF on serum Lp-PLA2 and S100B protein in patients with acute cere-bral infarction

Objective To study the influence of oxiracetam plus mouse nerve growth factor（mNGF） on serum lysophosphatidic acid 2（Lp-PLA2） and S100B protein in patients with acute cerebral infarction. Methods 124 patients with acute cerebral infarction were randomly divided into the observation group（ n = 62 cases） and the control group （ n = 62 cases）. The patients in the control group were treated through the conventional treatment,while the patients in the observation group were treated by oxiracetam plus mNGF on the basis of conventional therapy. They were treated for 21 days. Serum Lp-PLA2 and S100B were detected. Results The total effective rate of the observationgroup was 98.4% ,which was significantly higher than 90.3% of the control group （ X2 = 3.96 ,P 〈 O. 05 ）. Serum LpPLA2 and S100B were decreased in two groups after treatment. Serum Lp-PLA2 and SIOOB in the observation group were lower than those in the control group （ t = 20.9091,3. 7273, all P 〈 0.05 ）. Conclusion Oxiracetam plus mNGF can decrease serum Lp-PLA2 and mNGF in patients with acute cerebral infarction. Key words: Cerebral infarction; Oxiracetam; Nerve growth factor; Phospholipases A ; S100 proteins

Observation on clinical effect of oxiracetam combined with nimodipine in the treatment of vascular dementia

Objective To observe the clinical effects of oxiracetam combined with nimodipine in the treatment of vascular dementia.Methods 80 patients with vascular dementia in our hospital from May 2011 to March 2013 were randomly divided into observation group and control group,40 cases in each group.Observation group was given oxiracetam combined with nimodipine based on the general conventional method,and control group was given only general conventional method.Then the curative effects of two groups were analyzed and compared.Results After treatment,the clinical effect,MMSE grade,and ADL grade in the observation group were significantly better than those in the control group.Conclusion The curative effect of the oxiracetam combined with nimodipine in the treatment of vascular dementia is exact,which has collaborative strengthening effect.It is worthy to be popularized in clinic. Key words: Oxiracetam; Nimodipine; Vascular dementia

ChemInform Abstract: New Synthesis of (R)-GABOB (V) and (R)-Oxiracetam

ChemInform Abstract: New Synthesis of (R)-GABOB (V) and (R)-Oxiracetam

Oxiracetam pre- but not post-treatment prevented social recognition deficits produced with trimethyltin in rats

The social recognition paradigm was used to investigate the effect of trimethyltin (TMT) in adult male rats. Consequently, the effect of chronic oxiracetam (OXI) treatment in TMT impaired animals was evaluated. In all experiments, a behavioural testing was performed 3 weeks after TMT administration. Experiment 1: A single TMT oral dose, 5 and 7.5 but not 2.5 mg/kg, impaired the natural ability of the adults to recognize a juvenile conspecific that they encountered 30 min before. The dose of 5 mg/kg TMT was chosen to be used in subsequent experiments. Experiment 2: Chronic OXI pre- + post-treatment, daily 3 or 30 mg/kg sc for 7 days before and 7 days after the insult, protected the adults against recognition deficit produced by TMT. Experiment 3: OXI pre- but not post-treatment (always 3 and 30 mg/kg) had beneficial effects on the social recognition. The findings suggest that social recognition ability of adult male rats pre-treated sufficiently long with OXI is resistant to the neurotoxicity effect of TMT.

Kynurenic acid and 5,7-dichlorokynurenic acids improve social and object recognition in male rats

The present study describes the effect of kynurenic (KYNA) and 5,7-dichlorokynurenic (DCKA) acids, acting as selective antagonists at the glycine site on the NMDA receptor complex, upon short-term memory of male rats. Oxiracetam (OXIR) or pramiracetam (PRAM) were used as reference compounds. In the social recognition test, adult animals were injected SC with a drug or vehicle immediately after the first exposure to a juvenile male, 21-24 days old, and reexposed to the same or a novel juvenile 120 min later. Time spent by adults in social investigation of juveniles was measured. Animals treated with KYNA or DCKA (0.3, 3 and 30 mg/kg in both cases) and OXIR (30 and 60 mg/kg) had significantly reduced investigation time when reexposed to the same juvenile as compared to controls. No reduction of investigation time was found in those drugged animals reexposed to a novel juvenile. The findings suggest that KYNA and DCKA improved retention of memory for olfactory stimuli in adult male rats. In the object recognition test, the duration of exploration of two identical objects during the sample trial and the familiar and a new object during the choice trial, performed 60 min later, was evaluated. Drugs or vehicles were administered SC 30 min prior to the sample trial. On choice one, animals treated with KYNA or DCKA (0.6 and 30 mg/kg in both cases) and PRAM (30 mg/kg) spent more time in exploring a new object than the familiar one as compared to controls. This suggests that the drugged animals were able to remember the familiar object.(ABSTRACT TRUNCATED AT 250 WORDS)

Anticonvulsant properties of levetiracetam in mice are not shared by nootropic drugs

A highly sensitive detection approach of resonance Rayleigh scattering spectra (RRS) is firstly applied to analyzing nootropic drugs including piracetam (PIR) and oxiracetam (OXI). In HCl-NaAc buffer solution (pH = 3.0), the OXI chelated with palladium (II) to form the chelate cation [Pd2·OXI]2 +, and then reacted with Congo red (CGR) by virtue of electrostatic attraction and hydrophobic force to form binary complex [Pd2·OXI]. CGR2, which could result in the great enhancement of RRS. The resonance Rayleigh scattering signal was recorded at λex = λem = 375 nm. This mixture complex not only has higher RRS, but also makes contribution to significant increase of fluorescence, and the same phenomena also were discovered in PIR. The enhanced RRS intensity is in proportion to the PIR and OXI concentration in the range of 0.03–3.0 μg mL− 1, and the detection limit (DL) of RRS method for PIR and OXI is 2.3 ng mL− 1 and 9.7 ng mL− 1. In addition, the DL of fluorescence method for PIR and OXI is 8.4 μg mL− 1 and 19.5 μg mL− 1. Obviously, the RRS is the highly sensitive method, and the recoveries of the two kinds of nootropic drugs were range from 100.4% to 101.8.0% with RSD (n = 5) from 1.1% to 3.1% by RRS method. This paper not only investigated the optimum conditions for detecting nootropics with using RRS method, but also focused on the reasons for enhancing RRS intensity and the reaction mechanism, which in order to firm and contract the resultant. Finally, The RRS method has been applied to detect nootropic drugs in human urine samples with satisfactory results.

Quantified EEG in different hypertensive rat strains and its modifications by oxiracetam (OXI)

Quantified EEG in different hypertensive rat strains and its modifications by oxiracetam (OXI)