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Malaria is a parasitic lethal disease caused by Plasmodium protozoa. The resistance and drugs’ side effects have led to numerous researches for alternative suitable drugs with better efficiency and lower toxicity In the present study, we investigated in vivo antimalarial effects of G2 linear dendrimer-based nano-chloroquine. After the preparation of nano dendrimer G2, chloroquine loading was done. Determine the characterization of particles were specified by DLS, SLS and SEM. The LC–MS and FTIR were used for verifying the nano dendrimer G2 and the loading of chloroquine into the compound. The Solubility N-chloroquine and measurement of drug release rate were done. Antiplasmodial activity of N-chloroquine on BALB/c mice was performed by the microscope and enzymatic methods. At the end, In vivo toxicity of N-chloroquine on tissues was assayed. The RBC morphology and enzyme levels were identified. The results showed the synthesized N-chloroquine had suitable size and solubility. Highest inhibitory effect on Plasmodium parasitic growth was observed at 16 mg/kg dose of N-chloroquine, which eliminated 95% of the parasites (p > 0.05). ED50 is observed at 7.7 mg/kg of N-chloroquine dose. Biochemical findings showed the synthesized N-chloroquine was safer than chloroquine. The N-chloroquine no adverse effects were observed in examined tissues. Due to the better effect of the synthesized N-chloroquine on Plasmodium berghei in mice compared to chloroquine, this nanoparticle can be considered as an effective anti-plasmodium compound while more comprehensive research is recommended.

Abuse of alcohol triggers neurodegeneration in human brain. Minocycline has characteristics conferring neuroprotection. Current study evaluates the role of the CREB-BDNF signaling pathway in mediating minocycline's neuroprotective effects against alcohol-induced neurodegeneration. Seventy adult male rats were randomly split into groups 1 and 2 that received saline and alcohol (2 g/kg/day by gavage, once daily), respectively, and groups 3, 4, 5, and 6 were treated simultaneously with alcohol and minocycline (10, 20, 30 and 40 mg/kg I.P, respectively) for 21 days. Group 7 received minocycline alone (40 mg/kg, i.p) for 21 days. Morris water maze (MWM) has been used to assess cognitive activity. Hippocampal neurodegenerative and histological parameters as well as cyclic AMP response element-binding protein (CREB) and brain-derived neurotrophic factor (BDNF) levels were assessed. Alcohol impaired cognition, and concurrent therapy with various minocycline doses attenuated alcohol-induced cognition disturbances. Additionally, alcohol administration boosted lipid peroxidation and levels of glutathione in oxidized form (GSSG), tumor necrosis factor alpha (TNF-α), interleukin 1 beta (IL-1β), and Bax protein, while decreased reducing type of glutathione (GSH), Bcl-2 protein, phosphorylated CREB, and BDNF levels in rat hippocampus. Alcohol also decreased the activity in the hippocampus of superoxide dismutase (SOD), glutathione peroxidase (GPx), and glutathione reductase (GR). In comparison, minocycline attenuated alcohol-induced neurodegeneration; elevating expression levels of P-CREB and BDNF and inhibited alcohol induced histopathological changes in both dentate gyrus (DG) and CA1 of hippocampus. Thus, minocycline is likely to provide neuroprotection against alcohol-induced neurodegeneration through mediation of the P-CREB/BDNF signaling pathway.

Proton pump inhibitors (PPIs) are one of the highly prescribed or over-the-counter available medications among Iranians, mainly to treat conditions such as helicobacter pylori infection, gastroesophageal reflux disease or frequent heartburn. In recent years, several reports have shown potential adverse effects of PPI administration among which cardiovascular adverse events, myocardial infarction and chronic kidney disease are considered as the greatest risks. Recent addition of proton pump inhibitors to the list of medications on Beers Criteria of Potentially Inappropriate Drugs has arisen significant concerns about their safety. This review aims at providing an up-to date overview of PPIs indications and their pharmacogenomics and pharmacokinetics in Iranian population. The focus of this review is on PPIs regimens in Iranian population and then it is compared with the reported studies performed on other ethnic groups around the world. An extensive review of the literature was carried out and data under various sections were identified using a computerized literature search via Pubmed, Web of Science, Google Scholar and some local search engines. All abstracts and full text articles were examined and most relevant papers were selected for inclusion in this review. Also several expert internalists were interviewed for their clinical experiences in this field.

Methylphenidate (MPH) abuse causes adverse neurobehavioral and neurochemical effects. Some herbal components such as crocin have shown neuroprotective properties. The current study evaluates the potential role of the cyclic AMP response element binding protein (CREB)‑brain‑derived neurotrophic factor (BDNF) signaling pathway in mediating the neuroprotective effects of crocin against MPH‑induced neurotoxicity in rats. Seventy adult male rats were randomly divided into seven groups. Group 1 and 2 received 0.7 ml/rat of normal saline and 10 mg/kg of MPH, respectively. Groups 3, 4, 5, and 6 were treated simultaneously with MPH (10 mg/kg) and crocin (10, 20, 40, and 80 mg/kg, respectively) for 21 days. Group 7 was treated with crocin (80 mg/kg) alone for 21 days. The Morris water maze (MWM) and open field test were used to assess cognitive and locomotor activities. Hippocampal neurotoxicity parameters and levels of BDNF and CREB were evaluated. Simultaneous treatment with various doses of crocin reduced the MPH‑induced cognition disturbances and hyperlocomotion. In addition, lipid peroxidation increased with MPH treatment and levels of the oxidized forms of glutathione (GSSG), interleukin 1 beta (IL‑1β), tumor necrosis factor alpha (TNF‑α), and Bax increased. MPH treatment decreased levels of the reduced form of glutathione (GSH), P‑CREB, Bcl‑2, and BDNF in the hippocampus. MPH also reduced activity of superoxide dismutase, glutathione peroxidase, and glutathione reductase in the hippocampus. In contrast, crocin attenuated MPH‑induced oxidative stress, inflammation, and apoptosis, and increased levels of P‑CREB and BDNF. Thus, crocin - likely via stimulation of the P‑CREB/BDNF signaling pathway - displayed neuroprotection against MPH‑induced neurotoxicity.

Plantago major (P. major) has traditionally been used in Iranian Persian medicine to treat gastrointestinal ulcers and bleeding.This study aimed to investigate the anti-inflammatory effects of the leaf and seed extracts of P. major in rats with acetic acid-induced ulcerative colitis (UC).To this end, 49 rats were randomly divided into seven groups. UC was induced in all groups but the control (vehicle) group using a single intra-rectal administration of 2 ml of 4% acetic acid. Other groups received daily intraperitoneal (i.p.) injections of the seed extract of P. major (400 mg/kg and 700 mg/kg), the leaf extract of P. major (400 mg/kg and 700 mg/kg), and sulfasalazine (400 mg/kg) for seven consecutive days, respectively. The rats' rectum was surgically removed and evaluated for macroscopic and microscopic damage. The tissue levels of oxidative stress and inflammatory markers were measured using the ELISA method.The high-dose leaf extract significantly decreased ulcer index and histopathologic damage as well as the tissue levels of IL-6, TNF-α, PGE2, IL-1β, MPO, and MDA compared to the damage group. The low-dose leaf extract also significantly reduced the levels of some markers. The seed extract in the two used doses caused a modest decrease in the histopathological damages and ulcer index.P. major leaf extract effectively reduces inflammation and mucosal damage in rats with UC, especially when administered in high doses. P. major seed extract has minimal protective effects on UC.

Background Methamphetamine is a neuro-stimulant with neurodegenerative effects, and ambiguous mechanism of action. Metformin is an antidiabetic agent with neuroprotective properties but not fully understood mechanisms. The present study investigated the molecular basis of metformin neuroprotection against methamphetamine-induced neurodegeneration. Brief method Sixty adult male rats were randomly divided into six groups: group 1 (received normal saline), group 2 (received 10 mg/kg of methamphetamine) and groups 3, 4, 5 and 6 [received methamphetamine (10 mg/kg) plus metformin (50, 75, 100 and 150 mg/kg) respectively]. Elevated Plus Maze (EPM), Open Field Test (OFT), Forced Swim Test (FST), Tail Suspension Test (TST) and Morris Water Maze (MWM) were used to assess the level of anxiety, depression and cognition in experimental animals. Also animals’ hippocampus were isolated and oxidative stress and inflammatory parameters and expression of total and phosphorylated forms of cAMP response element binding (CREB), brain-derived neurotrophic factor (BDNF), protein kinase B (Akt) and glycogen synthase kinase 3 (GSK3) proteins were evaluated by ELISA method. Results According to the data obtained, methamphetamine caused significant depression, anxiety, motor activity disturbances and cognition impairment in experimental animals. Metformin, in all used doses, decreased methamphetamine induced behavioral disturbances. Also chronic administration of methamphetamine could increase malondialdehyde (MDA), tumor necrosis factor-Alpha (TNF-α) and interleukine-1 beta (IL-1β) in rats, while caused reduction of superoxide dismutase (SOD), glutathione peroxidase (GPx) and glutathione reductase (GR) activities. Metformin, especially in high doses, could prevent these malicious effects of methamphetamine. Also Metformin could activate CREB (both forms), BDNF and Akt (both forms) proteins’ expression and inhibited GSK3 (both forms) protein expression in methamphetamine treated rats. Significance According to obtained data, metformin could protect the brain against methamphetamine-induced neurodegeneration probably by mediation of CREB/BDNF or Akt/GSK3 signaling pathways. These data suggested that CREB/BDNF or Akt/GSK3 signaling pathways may have a critical role in methamphetamine induced neurotoxicity and/or neuroprotective effects of metformin.

The drastic decrease in estrogen levels in menopausal women can elevate bone resorption and osteoporosis. Cornus mas extract (C. mas extract) is a potential candidate for treating menopausal-related bone complications because of its phytoestrogen and anti-inflammatory contents. It was an interventional double-blind placebo-controlled randomized study. Eighty-four women aged 45-60 years old were randomly allocated to either the extract group receiving 3 capsules of 300 mg C. mas extract or the placebo group receiving 3 capsules of 300 mg of starch powder per day for 8 weeks. Then, venous blood was used to measure bone-specific alkaline phosphatase (BAP), osteocalcin (OC), C-terminal telopeptide (TC) as well as serum levels of PTH and hsCRP. Our results indicated the decrease in alkaline phosphatase, PTH, and as an inflammation biomarker, hsCRP, between two groups at the end of the study. No statistically significant difference was observed in telopeptide C, osteocalcin, and calcium between the placebo and extract groups after 8 weeks of intervention. In conclusion, the results indicate that the C. mas extract supplement of 900 mg/day may decrease levels of BAP, PTH, and hsCRP. However, this intervention had no beneficial effect on OC and TC in healthy postmenopausal women.

Propose/aim of study: Forced exercise can act as a neuroprotective factor and cognitive enhancer. The aim of the current study was to evaluate the effects of forced exercise on topiramate (TPM) induced cognitive impairment and also on TPM anti-seizure activity and neurodegeneration status after seizure.Material and method: Forty adult male rats were divided into four groups receiving normal saline, TPM (100 mg/kg), TPM in combination with forced exercise and forced exercise only respectively for 21 days. MWM test, and PTZ induced seizure were used and some oxidative, inflammatory and apoptotic biomarkers were measured for assessment of experimental animals.Results: Forced exercise in combination with TPM could abolish the TPM induced cognitive impairment and potentiates its anti-seizure activity. Also forced exercise in combination with TPM decreased malondialdehyde (MDA), tumor necrosis factor alpha (TNF-α) and interleukin-1 beta (IL-1β) and Bax protein, while caused increase in superoxide dismutase (SOD), glutathione peroxidase (GPx) and glutathione reductase (GR) activities after PTZ administration.Conclusion: It seems that forced exercise could act as an adjunct therapy with TPM for management of induced cognitive impairment and can also potentiate TPM antiepileptic and neuroprotective effects.

Many obstacles compromise the efficacy of bone marrow mesenchymal stem cells (BM-MSCs) by inducing apoptosis in the grafted BM-MSCs. The current study investigates the effect of melatonin on important mediators involved in survival of BM-MSCs in hydrogen peroxide (H2O2) apoptosis model. In brief, BM-MSCs were isolated, treated with melatonin, and then exposed to H2O2. Their viability was assessed by MTT assay and apoptotic fractions were evaluated through Annexin V, Hoechst staining, and ADP/ATP ratio. Oxidative stress biomarkers including ROS, total antioxidant power (TAP), superoxide dismutase (SOD) and catalase (CAT) activity, glutathione (GSH), thiol molecules, and lipid peroxidation (LPO) levels were determined. Secretion of inflammatory cytokines (TNF-α and IL-6) were measured by ELISA assay. The protein expression of caspase-3, Bax, and Bcl-2, was also evaluated by Western blotting. Melatonin pretreatment significantly increased viability and decreased apoptotic fraction of H2O2-exposed BM-MSCs. Melatonin also decreased ROS generation, as well as increasing the activity of SOD and CAT enzymes and GSH content. Secretion of inflammatory cytokines in H2O2-exposed cells was also reduced by melatonin. Expression of caspase-3 and Bax proteins in H2O2-exposed cells was diminished by melatonin pretreatment. The findings suggest that melatonin may be an effective protective agent against H2O2-induced oxidative stress and apoptosis in MSC.

BACKGROUND AND PURPOSE Epilepsy is one of the most common serious neurological conditions. The current therapeutic treatment of epilepsy with modern antiepileptic drugs is associated with side effects, dose-related and chronic toxicity, and teratogenic effects and in approximately 30% of the patients is ineffective. Alpinia officinarum is used in Iranian traditional medicine for treatment of different diseases like back pain and seizure. METHODS In this study, anticonvulsant effects of hydroalcoholic extract of Alpinia officinarum rhizomes were examined by using pentylentetrazole (PTZ) model in mice. Alpinia officinarum rhizomes extract (200, 400 and 600 mg/kg), diazepam (1 mg/kg) and normal saline (10 mL/kg) were injected (ip) 30 minutes before PTZ (90 mg/kg, ip). The time taken before the onset of clonic convulsions, the duration of colonic convulsions, and the percentage of seizure and mortality protection were recorded. For further clarification of the mechanism of action for Alpinia officinarum, flumazenil (2 mg/kg, ip) and naloxone (5 mg/kg, ip) were also injected 5 minutes before Alpinia officinarum extract. RESULTS Alpinia officinarum extract at the doses of 200 and 400 mg/kg prolonged the time of onset of seizure and decreased the duration of seizures compared to control (saline) group (p < 0.05). At the dose of 600 mg/kg, percentage of seizure protection was 16.66%. Naloxone and flumazenil could suppress anticonvulsant effects of Alpinia officinarum. CONCLUSIONS It seems that Alpinia officinarum could be a good candidate and be useful for seizure control and treatment, and in these effects, opioid and benzodiazepine receptors might probably be involved.

Prolonged abuse of methylphenidate (MPH) often causes neuronal damage. Topiramate (TPM) has neuroprotective properties, but its mechanism of action remains unclear. The current study evaluates in vivo role of various doses of TPM (10, 30, 50, 70 and 100mg/kg) and its possible mechanisms against MPH-induced hippocampal oxidative stress, inflammation and apoptosis, in absence and presence of different receptor agonists and antagonists. Domoic acid (DOM) as AMPA/kainate receptor agonist, bicuculline (BIC) as GABAA receptor antagonist, ketamine (KET) as NMDA receptor antagonist, yohimbine (YOH) as ɑ2 adrenergic receptor antagonist and haloperidole (HAL) as D2 dopamine receptor antagonist was used. Open Field Test (OFT) was used to investigate the disturbances in motor activity. Hippocampal oxidative, anti-oxidant and inflammatory parameters and apoptotic factors were studied. Expressions of BDNF at gene and protein levels were also evaluated. Crystal violet staining was performed to determine neuronal cell density. TPM (70 and 100mg/kg) reduced MPH-induced rise in lipid peroxidation, oxidized form of glutathione (GSSG), IL-1β and TNF-α levels, Bax expression and motor activity disturbances. In addition, TPM treatment increased BDNF gene and protein expressions, Bcl-2 expression, the level of reduced form of glutathione (GSH) and activities of enzymes superoxide dismutase, glutathione peroxidase and glutathione reductase.TPM also inhibited MPH-induced hippocampal degeneration. Pretreatment of animals with DOM, BIC, KET and YOH inhibited TPM-induced neuroprotection and increased oxidative stress, neuroinflammation, neuroapoptosis and neurodegeneration while reducing BDNF expressions. Thus, TPM by interacting with AMPA/kainate, GABAA, NMDA and ɑ2-adrenergic receptors improves BDNF expression and acts as a neuroprotective agent against MPH-induced neurodegeneration.

Chronic abuse of methylphenidate (MPH) can cause serious neurotoxicity. The neuroprotective effects of topiramate (TPM) were approved, but its putative mechanism remains unclear. In current study the role of CREB/BDNF signaling pathway in TPM protection against methylphenidate-induced neurotoxicity in rat hippocampus was evaluated. 60 adult male rats were divided randomly into six groups. Groups received MPH (10 mg/kg) only and concurrently with TPM (50 mg/kg and 100 mg/kg) and TPM (50 and 100 mg/kg) only for 14 days. Open field test (OFT) was used to investigate motor activity. Some biomarkers of apoptotic, anti-apoptotic, oxidative, antioxidant and inflammatory factors were also measured in hippocampus. Expression of total (inactive) and phosphorylated (active) CREB and BDNF were also measured in gene and protein levels in dentate gyrus (DG) and CA1 areas of hippocampus. MPH caused significant decreases in motor activity in OFT while TPM (50 and 100 mg/kg) inhibited MPH-induced decreases in motor activity. On the other hand, MPH caused remarkable increases in Bax protein level, lipid peroxidation, catalase activity, IL-1β and TNF-α levels in hippocampal tissue. MPH also caused significant decreases of superoxide dismutase, activity and also decreased CREB, in both forms, BDNF and Bcl-2 protein levels. TPM, by the mentioned doses, attenuated these effects and increased superoxide dismutase, glutathione peroxidase and glutathione reductase activities and also increased CREB, in both forms, BDNF and Bcl-2 protein levels and inhibited MPH induced increase in Bax protein level, lipid peroxidation, catalase activity, IL-1β and TNF-α levels. TPM also inhibited MPH induced decreases in cell number and changes in cell shapes in DG and CA1 areas. TPM can probably act as a neuroprotective agent against MPH induced neurotoxicity and this might have been mediated by CREB/BDNF signaling pathway.

Background Alcohol abuse causes severe damage to the brain neurons. Studies have reported the neuroprotective effects of curcumin against alcohol-induced neurodegeneration. However, the precise mechanism of action remains unclear. Methods Seventy rats were equally divided into 7 groups (10 rats per group). Group 1 received normal saline (0.7 ml/rat) and group 2 received alcohol (2 g/kg/day) for 21 days. Groups 3, 4, 5 and 6 concurrently received alcohol (2 g/kg/day) and curcumin (10, 20, 40 and 60 mg/kg, respectively) for 21 days. Animals in group 7 self- administered alcohol for 21 days. Group 8 treated with curcumin (60 mg/kg, i.p.) alone for 21 days. Open Field Test (OFT) was used to investigate motor activity in rats. Hippocampal oxidative, antioxidative and inflammatory factors were evaluated. Furthermore, brain cyclic adenosine monophosphate (cAMP) response element binding protein (CREB) and brain derived neurotrophic factor (BDNF) levels were studied at gene level by reverse transcriptase polymerase chain reaction (RT-PCR). In addition, protein expression for BDNF, CREB, phosphorylated CREB (CREB-P), Bax and Bcl-2 was determined by western blotting. Result Voluntary and involuntary administration of alcohol altered motor activity in OFT, and curcumin treatment inhibited this alcohol-induced motor disturbance. Also, alcohol administration augmented lipid peroxidation, mitochondrial oxidized glutathione (GSSG), interleukin-1 beta (IL-1β), tumor necrosis factor-alpha (TNF-α) and Bax levels in isolated hippocampal tissues. Furthermore, alcohol-induced significant reduction were observed in reduced form of glutathione (GSH), superoxide dismutase (SOD), glutathione peroxidase (GPx) and glutathione reductase (GR) activities and CREB, BDNF and Bcl-2 levels. Also curcumin alone did not change the behavior and biochemical and molecular parameters. Conclusion Curcumin can act as a neuroprotective agent against neurodegenerative effects of alcohol abuse, probably via activation of CREB-BDNF signaling pathway.

This study investigated the anticonvulsant activity and possible mechanism of action of an aqueous solution of Dorema ammoniacum gum (DAG) which has been used traditionally in the treatment of convulsions.In this study, the anticonvulsant activity of DAG was examined using the pentylentetrazole (PTZ) model in mice. Thirty male albino mice were divided randomly and equally to 5 groups, and pretreated with normal saline, diazepam, or various doses of DAG (500, 700, and 1000 mg/kg, i.p.), prior to the injection of PTZ (60 mg/kg, i.p.). The latency and duration of seizures were recorded 30 min after PTZ injection. Pretreatments with naloxone and flumazenil in different groups were studied to further clarify the mechanisms of the anticonvulsant action. Phytochemical screening and thin layer chromatography (TLC) fingerprinting of ammoniacum gum was also determined. DAG showed significant anticonvulsant activity at all doses used. The gum delayed both the onset and the duration of seizures induced by PTZ. Treatment with flumazenil before DAG (700 mg/kg) inhibited the effect of gum on seizure duration and latency to some extent and administration of naloxone before DAG also significantly inhibited changes in latency and duration of seizure produced by DAG. The percentage inhibition was greater with naloxone than with flumazenil. This study showed that DAG had significant anticonvulsant activity in PTZ-induced seizures, and GABAergic and opioid systems may be involved. More studies are needed to further investigate its detailed mechanism.

Background: Duloxetine is used for treating depression and anxiety. The current study evaluated the effects of duloxetine against methamphetamine withdrawal-induced anxiety, depression, and motor disturbances and methamphetamine use-induced cognitive impairments. Materials and Methods: Ninety-six adult male rats were used for two independent experiments. Each experiment consisted of Groups 1 and 2 which received normal saline (0.2 ml/rat) and methamphetamine (10 mg/kg) respectively, Groups 3, 4, and 5 received both methamphetamine and duloxetine at doses of 5, 10, and 15 mg/kg, respectively. Groups 6, 7, and 8 received 5, 10, and 15 mg/kg of duloxetine, respectively. All administrations were performed for 21 days. In experiment 1, elevated plus maze (EPM), open-field test (OFT), forced swim test (FST), and tail suspension test (TST) were used to examine anxiety and depression in animals during withdrawal period. In experiment 2, Morris water maze (MWM) test was used to assess the effect of methamphetamine use followed by duloxetine treatment, on learning and memory. In the experiments, the expression of cyclic AMP response element binding (CREB) and brain-derived neurotrophic factor (BDNF) proteins were evaluated using enzyme-linked immunosorbent assay. Results: In the first experiment, duloxetine at all doses attenuated methamphetamine withdrawal induced-depression, anxiety, and motor disturbances in FST, OFT, EPM, and TST. In the second experiment, duloxetine at all doses attenuated methamphetamine use-induced cognitive impairment in MWM. In both experiments, duloxetine activated cAMP, CREB, and BDNF proteins' expression in methamphetamine-treated rats. Conclusions: Duloxetine can protect the brain against methamphetamine withdrawal-induced mood and motor disturbances and can also inhibit methamphetamine-induced cognitive impairment, possibly via cAMP/CREB/BDNF signaling pathway.

Neurodegeneration induced by methylphenidate (MPH), as a central stimulant with unknown long-term consequences, in adult rats’ brain and the possible mechanisms involved were studied. Rats were acutely treated with MPH in presence and absence of some receptor antagonists such as ketamine, topiramate, yohimibine and haloperidol. Motor activity and anxiety level in rats were monitored. Anti-oxidant and inflammatory parameters were also measured in isolated hippocampus and cerebral cortex. MPH treated groups (10 and 20 mg/kg) demonstrated anxiety-like behavior and increased motor activity. MPH significantly increased lipid peroxidation, GSSG content, IL-1β and TNF-α levels in isolated tissues, and also significantly reduced GSH content, superoxide dismutase, glutathione peroxidase and glutathione reductase activities in hippocampus and cerebral cortex. Pretreatment of animals by receptor antagonists caused inhibition of MPH-induced motor activity disturbances and anxiety-like behavior. Pretreatment of animals by ketamine, topiramate and yohimibine inhibited the MPH-induced oxidative stress and inflammation; it significantly decreased lipid peroxidation, GSSG level, IL-1β and TNF-α levels and increased GSH content, superoxide dismutase, glutathione peroxidase and glutathione reductase activities in hippocampus and cerebral cortex of acutely MPH treated rats. Pretreatment with haloperidole did not cause any change in MPH-induced oxidative stress and inflammation. In conclusion, acute administration of high doses of MPH can cause oxidative and inflammatory changes in brain cells and induce neurodegeneration in hippocampus and cerebral cortex of adult rats and these changes might probably be mediated by glutamate (NMDA or AMPA) and/or α2 adrenergic receptors. This article is protected by copyright. All rights reserved.

Methylphenidate (MPH) is a neural stimulant with unclear neurochemical and behavioral effects. Lithium is a neuroprotective agent in use clinically for the management of manic-depressive and other neurodegenerative disorders. This study investigated the protective effect of lithium on MPH-induced oxidative stress, anxiety, depression and cognition impairment. Forty-eight adult male rats were divided randomly and equally into 6 groups. Treatment groups were received MPH (10mg/kg) and various doses of lithium (75, 150 and 300mg/kg) simultaneously and also lithium (150mg/kg) alone for 21 days. Elevated Plus Maze and Forced Swim Test were used to determine the level of anxiety and depression in animals. Morris Water Maze was used to evaluate spatial learning and memory. The hippocampi of rats were isolated and the level and activity of oxidative, anti-oxidant and inflammatory factors were measured. Also brain derived neurotropic factor expression level was measured by RT-PCR and western blotting. MPH (10mg/kg) caused behaviors indicative of anxiety and depression-like phenotypes in EPM and FST and cognition impairment in MWM. While lithium in all mentioned doses inhibited these effects. Treatment with MPH significantly increased lipid peroxidation, mitochondrial GSH content and IL-1β and TNF-α levels in isolated hippocampal cells. Moreover superoxide dismutase and glutathione peroxidase activities and BDNF expression remarkably decreased. Various doses of lithium attenuated these effects and significantly mitigated MPH-induced oxidative damage, inflammation and increased BDNF expression level. Lithium has the potential to act as a neuroprotective agent against MPH induced toxicity in rat brain and this might be mediated by BDNF expression in hippocampus of rats.

Abuses of methylphenidate (MPH) as psychostimulant cause neural damage of brain cells. Neuroprotective properties of topiramate (TPM) have been indicated in several studies but its exact mechanism of action remains unclear. The current study evaluates protective role of various doses of TPM and its mechanism of action in MPH induced oxidative stress and inflammation. The neuroprotective effects of various doses of TPM against MPH induced oxidative stress and inflammation were evaluated and then the action of TPM was studied in presence of domoic acid (DOM), as AMPA/kainate receptor agonist and bicuculline (BIC) as GABA A receptor antagonist, in isolated rat hippocampus. Open Field Test (OFT) was used to investigate motor activity changes. Oxidative, antioxidant and inflammatory factors were measured in isolated hippocampus. TPM (70 and 100 mg/kg) decreased MPH induced motor activity disturbances and inhibit MPH induced oxidative stress and inflammation. On the other hand pretreatment of animals with DOM or BIC, inhibit this effect of TPM and potentiate MPH induced motor activity disturbances and increased lipid peroxidation, mitochondrial oxidized form of glutathione (GSSG) level, interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) in isolated hippocampal cells and decreased reduced form of glutathione (GSH) level, superoxide dismutase, glutathione peroxidase and glutathione reductase activity. It seems that TPM can protect cells of hippocampus from oxidative stress and neuroinflammation and it could be partly by activation of GABA A receptor and inhibition of AMPA/kainite receptor.

The risk of serious side-effects such as nephrotoxicity is the principal limitation of gentamicin (GEN) therapeutic efficacy. Oxidative stress is considered to be an important mediator of GEN-induced nephrotoxicity. The present study was designed to evaluate the efficacy of the combination of melatonin (MT) plus atorvastatin (ATO) against GEN-induced nephrotoxicity in rats. We utilized 30 male Wistar albino rats allocated in 5 groups, each containing 6 rats: control, GEN (100 mg/kg/day), ATO (10 mg/kg/day) + GEN, MT (20 mg/kg/day) + GEN, and ATO (10 mg/kg/day) plus MT (20 mg/kg/day) + GEN. Kidney weight, serum creatinine and urea concentration, renal ROS, MDA, GSH levels, SOD, and CAT activity were determined. GEN-induced nephrotoxicity was evidenced by marked elevations in serum urea and creatinine, kidney weight, renal ROS, and MDA levels and reduction in renal GSH level, SOD and CAT activity. MT pretreatment significantly lowered the elevated serum creatinine concentration, kidney weight, renal ROS and MDA levels. However ATO could not reduce these parameters, but similarly to MT, it was able to enhance the renal GSH level, CAT and SOD activity. In addition, a combination therapy of MT plus ATO enhanced the beneficial effects of ATO, while not changing the effects of MT effects or even improving them. The present study indicates that a combination therapy of MT plus ATO can attenuate renal injury in rats treated with GEN, possibly by reducing oxidative stress, and it seems that MT can enhance the beneficial effects of ATO.

Methylphenidate (MPH) abuse causes neurodegeneration. The neuroprotective effects of topiramate (TPM) have been reported but its putative mechanism remains unclear. The current study evaluates the role of various doses of TPM on protection of rat hippocampal cells from MPH-induced oxidative stress and inflammation in vivo. Seventy adult male rats were divided into six groups. Group 1 received normal saline (0.7 mL/rat) and group 2 was injected with MPH (10 mg/kg) for 21 days. Groups 3, 4, 5, 6 and 7 concurrently were treated by MPH (10 mg/kg) and TPM (10, 30, 50, 70 and 100 mg/kg, intraperitoneally (i.p.)), respectively for 21 days. After drug administration, the open field test (OFT) was used to investigate motor activity. Oxidative, antioxidant and inflammatory factors were measured in isolated hippocampus. Also, the brain-derived neurotrophic factor (BDNF) level was measured by reverse transcriptase-polymerase chain reaction (RT-PCR) and Western blotting. Cresyl violet staining of Dentate Gyrus (DG) and CA1 cell layers of the hippocampus were also performed. MPH significantly disturbs motor activity in OFT and TPM (70 and 100 mg/kg) decreased this disturbance. Also MPH significantly increased lipid peroxidation, mitochondrial reduced state of glutathione (GSH) level, interleukin (IL)-1β and tumour necrosis factor (TNF)-α and BDNF level in isolated hippocampal cells. Also superoxide dismutase, glutathione peroxidase and glutathione reductase activity significantly decreased. Various doses of TPM attenuated these effects and significantly decreased MPH-induced oxidative damage, inflammation and hippocampal cell loss and increased BDNF level. This study suggests that TPM has the potential to be used as a neuroprotective agent against oxidative stress and neuroinflammation induced by frequent use of MPH.

Aim Neurodegeneration is one of the serious adverse effects of stimulant agents such as nicotine. Minocycline possess established neuroprotective properties. The role of CREB-BDNF signaling pathway in mediating the neuroprotective effects of minocycline against nicotine-induced neurodegeneration in rats was evaluated in current study. Methods Seventy adult male rats were divided randomly into seven groups. Group 1 and 2, received 0.7 ml/rat of normal saline (i.p) and nicotine (10 mg/kg, s.c) respectively. Groups 3, 4, 5 and 6, treated concurrently with nicotine (10 mg/kg) and minocycline (10, 20, 30 and 40 mg/kg, i.p, respectively) for 21 days. Group 7 received minocycline alone (40 mg/kg, i.p) for 21 days. From 17th to 21 st days of experiment, Morris water maze (MWM) was used to evaluate learning and spatial memory in rats treated in different groups. According to the critical role of hippocampus in cognitive behavior, hippocampal neurodegenerative parameters (oxidative stress and inflammatory biomarkers) and also cyclic AMP response element binding protein (CREB) and brain-derived neurotrophic factor (BDNF) levels were evaluated in isolated hippocampus in day 22 of experiment and after drug treatment. Also hippocampal cell density and tissue changes were evaluated by hematoxylin and eosin staining. Result Nicotine administration impaired the learning and spatial memory in rats and simultaneous treatment with various doses of minocycline attenuated the nicotine-induced cognition disturbances. In addition, nicotine treatment increased lipid peroxidation and the levels of oxidized form of glutathione (GSSG), interleukin 1 beta (IL-1β), tumor necrosis factor alpha (TNF-α), and Bax protein, while decreasing reduced form of glutathione (GSH), Bcl-2 protein, P-CREB and BDNF levels in the hippocampus of experimental animals. Nicotine also reduced the activity of superoxide dismutase (SOD), glutathione peroxidase (GPx) and glutathione reductase (GR) in the hippocampus. Minocycline attenuated nicotine-induced neurodegeneration and elevating CREB (both forms) and BDNF levels. Also minocycline treatment alone increases the cognitive activity and increased CREB (both forms) and BDNF levels and decreased oxidative stress, inflammation and apoptotic biomarkers. Minocycline at high doses cause inhibition of nicotine induced cell density and changes in both area of dentate gyrus (DG) and CA1 in hippocampus. Conclusion It can be concluded that minocycline, probably through activation of P-CREB/BDNF signaling pathway, confers neuroprotection against nicotine-induced neurodegeneration in rat hippocampus.

5-iodo-2-deoxyuridine (IUdR) has been demonstrated to induce an appreciable radiosensitizing effect on glioblastoma patients, but due to the short circulation half-life times and failure to pass through the blood-brain barrier (BBB), its clinical use is limited. Accordingly, in this study, we used magnetic graphene oxide (NGO/SPIONs) nanoparticles coated with PLGA polymer as a dynamic nanocarrier for IUdR and, evaluated its sensitizing enhancement ratio in combination with a single dose X-ray at clinically megavoltage energies for treatment of C6 glioma rats. Nanoparticles were characterized using Zetasizer and TEM microscopy, and in vitro biocompatibility of nanoparticles was assessed with MTT assay. IUdR/MNPs were intravenously administered under a magnetic field (1.3 T) on day 13 after the implantation of C6 cells. After a day following the injection, rats exposed with radiation (8 Gy). ICP-OES analysis data indicated an effective magnetic targeting, leading to remarkably improved penetration through the BBB. In vivo release analysis with HPLC indicated sustained release of IUdR and, prolonged the lifespan in plasma (P .01). In addition, our findings revealed a synergistic effect for IUdR/MNPs coupled with radiation, which significantly inhibited the tumor expansion (100%), prolonged the survival time (100%) and suppressed the anti-apoptotic response of glioma rats by increasing Bax/Bcl-2 ratio (2.13-fold) in compared with the radiation-only. In conclusion, besides high accumulation in targeted tumor sites, the newly developed IUdR/MNPs, also exhibited the ability of IUdR/MNPs to significantly enhance radiosensitizing effect, improve therapeutic efficacy and increase toxicity for glioma-bearing rats.

Chronic exposure to arsenic, an inducer of oxidative stress, is one of the major causes of male infertility. Therefore, the present study investigated the protective role of Ellagic acid (EA), as a natural antioxidant, against testicular toxicity evoked by arsenic. Thirty-five male Wistar rats were divided into 5 treatment groups. Group 1 served as control, group 2 were orally exposed to sodium arsenite (SA, 10 mg/kg; 21 days), groups 3 and 4 were initially exposed to SA for 7 days and then were treated with both EA (10 and 30 mg/kg) and SA up to 21 days, and group 5 was treated with EA for 14 days. After this period, biochemical and histopathological parameters were evaluated in serum samples and testicular tissue. SA markedly reduced levels of serum testosterone, total antioxidant capacity, reduced glutathione as well as the activity of antioxidant enzymes. Furthermore, SA enhanced levels of malondialdehyde, tumor necrosis factor-α, interleukin-1β and nitric oxide in testes. Treatment with EA was found to reduce testicular arsenic accumulation and oxidative stress parameters. In addition, EA improved the serum testosterone level, testicular antioxidant markers and histological parameters after exposure to SA. EA may emerge as a promising therapeutic option to protect testes from arsenic-induced toxicity through reducing oxidative stress and inflammatory responses.

BACKGROUND The Elaeagnus angustifolia fruit has been traditionally used in Iranian herbal medicine to treat diarrhea and rheumatoid arthritis. In the present study, the effects of E. angustifolia fruit extract on the acute and chronic phases of formalin-induced rat paw edema were examined. METHODS The acute and chronic anti-inflammatory effects of E. angustifolia fruit extract were investigated through the subcutaneous injection of 100 μL of formalin (2.5%) into a rat's hind paw. Thirty minutes before the procedure, the experimental groups were treated intraperitoneally with hydroalcoholic fruit extracts of E. angustifolia (concentrations of 100, 300, 700, and 1000 mg/kg); sodium salicylate (SS, 400 mg/kg) and distilled water were used as positive and negative control groups, respectively. Treatment with SS and the fruit extracts were performed daily for 8 days, and the degree of edema was measured by using mercury plethysmometer and digital caliper. RESULTS In the acute anti-inflammatory study, the extract showed a significant anti-inflammatory effect in a dose-dependent manner. The results of 1000 mg/kg of the extract was significantly different compared with the negative control group (p

Background : The neuroprotective effects of duloxetine and neurodegenerative effects of methamphetamine have been shown in previous studies, but their exact mechanism remain unclear. In the current study it involved molecular mechanisms of neuroprotective effects of duloxetine against methamphetamine induced neurodegeneration were clarified. Methods : About 40 adult male rats randomly were divided to 5 groups. Group 1 and 2, as control and methamphetamine treated, received normal saline and methamphetamine (10 mg/kg) respectively. Groups 3, 4 and 5 concurrently treated with methamphetamine and duloxetine at doses of 10, 20 and 30 mg/kg respectively. All treatments were undertaken for 21 days. On day 22 Open Field Test (OFT) were used to examine the level of motor activity disturbance and anxiety in animals. After that hippocampus was isolated from each rat and oxidative, antioxidant, inflammatory factors and also level or expression of total and phosphorylated forms of CREB and P‑CREB and BDNF proteins were measured. Results : Duloxetine in all mentioned doses could inhibit the effects of methamphetamine induced motor activity disturbance in MWM. Chronic abuse of methamphetamine could increase malondialdehyde (MDA), tumor necrosis factor‑Alpha (TNF‑ α ) and interleukine‑1beta (IL‑1 β ) while caused decreases in superoxide dismutase (SOD), glutathione peroxidase (GPx) and glutathione reductase (GR) activities and decreased CREB (both forms) and BDNF proteins, while duloxetine could prevent these malicious effects of methamphetamine. Conclusions : We conclude that P‑CREB/ BDNF signaling pathways might have critical role in duloxetine neuroprotective effects against methamphetamine induced neurodegeneration. Keyword : Duloxetine, methamphetamine, motor activity, neurodegeneration, P‑CREB/BDNF pathway

Nicotine abuse adversely affects brain and causes apoptotic neurodegeneration. Curcumin- a bright yellow chemical compound found in turmeric is associated with neuroprotective properties. The current study was designed to evaluate the role of CREB-BDNF signaling in mediating the neuroprotective effects of curcumin against nicotine-induced apoptosis, oxidative stress and inflammation in rats. Sixty adult male rats were divided randomly into six groups. Group 1 received 0.7 ml/rat normal saline, group 2 received 6 mg/kg nicotine. Groups 3, 4, 5 and 6 were treated concurrently with nicotine (6 mg/kg) and curcumin (10, 20, 40 and 60 mg/kg i.p. respectively) for 21 days. Open Field Test (OFT) was used to evaluate the motor activity. Hippocampal oxidative, anti-oxidant, inflammatory and apoptotic factors were evaluated. Furthermore, phosphorylated brain cyclic adenosine monophosphate (cAMP) response element binding protein (P-CREB) and brain derived neurotrophic factor (BDNF) levels were studied at gene and protein levels. We found that nicotine disturbed the motor activity in OFT and simultaneous treatment with curcumin (40 and 60 mg/kg) reduced the nicotine-induced motor activity disturbances. In addition, nicotine treatment increased lipid peroxidation and the levels of GSH, IL-1β, TNF-α and Bax, while reducing Bcl-2, P-CREB and BDNF levels in the hippocampus. Nicotine also reduced the activity of superoxide dismutase, glutathione peroxidase and glutathione reductase in hippocampus. In contrast, various doses of curcumin attenuated nicotine-induced apoptosis, oxidative stress and inflammation; while elevating P-CREB and BDNF levels. Thus, curcumin via activation of P-CREB/BDNF signaling pathway, confers neuroprotection against nicotine-induced inflammation, apoptosis and oxidative stress.

Evidence show that gamma-aminobutyric acid (GABA) receptors are involved in depression, so the aim of this study was to investigate the effect of nitrazepam as agonist of GABA A receptors on depression and curiosity in male mice and the role of potassium channel in antidepressant-like response. For this purpose, we studied the antidepressant-like properties of fluoxetine, nitrazepam, glibenclamide, and cromakalim by both forced swimming test (FST) and tail suspension test (TST). Animals were injected by various doses of nitrazepam (0.05, 0.1, and 0.5 mg/kg). Nitrazepam at dose of 0.5 mg/kg significantly decreased the immobility time compared to control group in both FST and TST. Fluoxetine also showed such a response. Co-administration of nitrazepam (0.05 mg/kg) with glibenclamide in TST (1 mg/kg) and in FST (0.3, 1 mg/kg) also showed antidepressant-like response. Beside, cromakalim (0.1 mg/kg) could reverse the antidepressant-like effect of nitrazepam (0.5 mg/kg) in both FST and TST, while cromakalim and glibenclamide alone could not change the immobility time compared to control group ( P> 0.05). The hole-board test revealed that nitrazepam at doses of 0.5 and 0.1 mg/kg could increase the activity of the animal’s head-dipping and boost the curiosity and exploration behavior of mice. The results of this study revealed that nitrazepam may possess antidepressant-like properties and this effect is dependent to potassium channels in both FST and TST.

Omeprazole is metabolized in the liver mainly by the polymorphic CYP2C19 enzyme. Considerable ethnic differences have been reported in the pharmacokinetics of omeprazole. The present study was conducted to evaluate the pharmacokinetic parameters of omeprazole after a single oral administration to a random Iranian population. Thirty healthy male subjects, aged 24–31 years, weighing 60–98 kg completed the study. Plasma concentrations of omeprazole were measured over a 12 h period after administration of a single oral dose of 20 mg omeprazole. The pharmacokinetic parameters were calculated from the plasma concentration–time profiles. Liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) was used to quantify 5-hydroxyomeprazole. The mean area under the concentration–time curve (AUC) from time zero to infinity (AUC∞) values of omeprazole and the corresponding coefficient of variation (CV%) was 987.3 ng h/ml (65%). In general, most subjects showed a normal distribution. Only one subject showed a very high AUC compared with the corresponding mean AUC level. This subject had the highest half-life and the lowest rate of elimination. The omeprazole metabolic ratio for this subject was 2.9, while for the others it was in the range 0.12–0.56. These results are consistent with previous literature that showed the existence of interindividual variability in omeprazole pharmacokinetics, even within a single ethnic group. Differences in the pharmacokinetics could be due to differences in the genetic make-up of subjects as found in their omeprazole metabolic ratios. Copyright © 2012 John Wiley & Sons, Ltd.

Background: Forced exercise can act as non-pharmacologic neuroprotective agent. In current study, we tried the involved molecular mechanisms of protective effects of forced exercise against methamphetamine induced neurodegeneration. Materials and Methods: Forty adult male rats were divided to Group 1 and 2 which received normal saline and methamphetamine (10 mg/kg) respectively for 30 days. Groups 3, 4 and 5 were treated with methamphetamine for first 15 days and then were treated by forced exercise, bupropion (20 mg/kg/day) or combination of them for the following 15 days. Between 26th and 30th days, Morris Water Maze (MWM) was used to evaluate the cognition. On day 31, hippocampus was isolated from each rat and oxidative, antioxidant and inflammatory factors also the level of total and phosphorylated forms of cAMP response element-binding protein (CREB) and brain derived neurotrophic factor (BDNF) proteins were also evaluated. Results: Chronic abuse of methamphetamine could decreases cognition and increase malondialdehyde (MDA), Tumor necrosis factor alpha (TNF-α) and interleukin-1 beta (IL-1β), while caused decreases in superoxide dismutase (SOD), glutathione peroxidase (GPx) and glutathione reductase (GR) activities all these changes was significant (P < 0.001) in compared to control group while treatment with bupropion, forced exercise and bupropion in combination with forced exercise could prevent all these malicious effects of methamphetamine (P < 0.001). Bupropion, forced exercise and bupropion in combination with forced exercise could activate CREB (both forms) and activates BDNF proteins' expression with P < 0.001 in methamphetamine treated rats. Conclusions: P-CREB/BDNF signaling pathways might have critical role in forced exercise protective effects against methamphetamine induced neurodegeneration.

This study investigated the anticonvulsant activity of Citrullus colocynthis fruit extract used traditionally in the treatment of convulsion. Albino mice were pretreated with extract in different doses (10, 25, 50, and 100 mg/kg), prior to injection of pentylenetetrazole. Animals received pretreatments with naloxone and flumazenil to further clarify the mechanisms of anticonvulsant action. The total flavonoid content of Citrullus colocynthis extract was also determined. Citrullus colocynthis hydroalcoholic extract with doses 25 and 50 mg/kg prolonged the onset of seizures and decreased the duration compared with control group. Pretreatment by flumazenil could inhibit the effect of Citrullus colocynthis on latency of seizure to some extent and administration of naloxone significantly inhibited changes in latency and duration of seizure produced by Citrullus colocynthis. This study showed that Citrullus colocynthis has significant anticonvulsant effect in pentylenetetrazole-induced seizures in mice, and these effects may be related to its effect on γ-aminobutyric acid-ergic and opioid systems. These results confirmed the traditional use of Citrullus colocynthis in Iranian traditional medicine.

Background: Methylphenidate (MPH) is a neural stimulant agent, which its neurochemical and behavioral effect remain unclear. Venlafaxine is a serotonin-norepinephrine reuptake inhibitor antidepressant, which was used for management of depression and anxiety. In this study, protective effects of venlafaxine on MPH induced anxiety, depression and cognition impairment were investigated. Methods: Forty-eight adult male rats were divided randomly to 5 groups. Group 1, received normal saline (0.2 ml/rat) for 21 days and served as control group. Group 2, received MPH (10 mg/kg) for 21 days. Groups, 3, 4, 5 and 6 concurrently were treated by MPH (10 mg/kg) and venlafaxine at doses of 25, 50, 75 and 100 mg/kg respectively for 21 days. On day 22, elevated plus maze (EPM), open field test (OFT), forced swim test (FST) and tail suspension test (TST) were used to investigate the level of anxiety and depression in animals. In addition, between days 17 and 21, Morris water maze (MWM) was used to evaluate the effect of MPH on spatial learning and memory. Results: MPH caused depression and anxiety in a dose-dependent manner in FST, OFT, EPM and TST, which were significantly different compared with control group. Furthermore, MPH can significantly attenuate the motor activity in OFT. Venlafaxine in all doses can attenuate MPH induced anxiety, depression and motor activity alterations. MPH also can disturb learning and memory in MWM, but venlafaxine did not alter this effect of MPH. Conclusions: We conclude that venlafaxine can be protective in the brain against MPH induced anxiety and depression.

Background The importance of inflammatory diseases and side effects of conventional drugs necessitate the finding of new anti-inflammatory agents from natural sources. In this study, for the first time, the anti-inflammatory and analgesic effects of the aqueous extract of Astragalus arbusculinus gum were evaluated in animal models. Methods Thirty-five male Wistar rats were divided into five groups and pretreated with different doses of A. arbusculinus gum extract before the injection of formalin. Paw edema was measured by a plethysmometer at time 0 and after 8 days and compared to controls. The analgesic effect of the extract was evaluated using the hot-plate test in 42 male albino mice. Results The extract of A. arbusculinus gum decreased the rat paw edema in a dose-dependent manner. The effect on inflammation of the highest dose of extract was comparable to sodium salicylate. Astragalus arbusculinus gum extract at doses of 300 and 1000 mg/kg showed analgesic effects comparable to sodium salicylate and morphine, respectively. A preliminary phytochemical study and the determination of the total phenolic content of the gum extract were performed for the first time. Conclusions The aqueous extract of A. arbusculinus gum reduced the inflammation and pain in a dose-dependent manner and is a good candidate for further studies of safety and efficacy. The clarification of active components of the plant is necessary.

A rapid, simple and sensitive HPLC assay was developed for the simultaneous determination of omeprazole and its major metabolites in human plasma using a solid-phase extraction procedure. Eluent (50 μL) was injected on an μBondapak C18 reversed-phase column (4.6 mm i.d., 250 mm; 10 μm). The mobile phase consisted of 0.05 m phosphate buffer (pH 7-5) and acetonitrile (75:25, v/v) at a flow rate of 0–8 mL min−1. UV detection was at 302 nm. Mean recovery was greater than 96% and the analytical responses were linear over the omeprazole concentration range of 50–2000 ng mL−1. The minimum detection limits were 10, 10 and 15 ng mL−1 for omeprazole, omeprazole sulphone and hydroxyomeprazole, respectively. The method was used to determine the plasma concentration of the respective analytes in four healthy volunteers after an oral dose of 40 mg omeprazole. The extraction procedure and HPLC method is simple, precise and quick, and suitable for the study of pharmacokinetic disposition and metabolism of omeprazole, which is extensively metabolized in man.

The aim of the present study was to assess the effects of the 5-HT1A receptor agonist 8-hydroxy-2-(di-n-propyIamino)tetralin (8-OH-DPAT) and flesinoxan in ring preparations of human basilar artery. 5-Hydroxytryptamine-(5-HT), 8-OH-DPAT and flesinoxan induced concentration-dependent contractions of human basilar artery, the rank order of agonist potency being 5-HT > 8-OH-DPAT ≈ flesinoxan. The rank order of maximum response, relative to 5-HT was 5-HT (100%) > 8-OH-DPAT (40.4 ± 4.4%) > flesinoxan (7.0 ± 2.3%). The contractile effects of 8-OH-DPAT werc blocked by phentolamine (10 μM) but not by labetalol (10 μM). Spiperone (1 μM) had no significant effect on either 5-HT or 8-OH-DPAT-induced contraction. howev

Sumatriptan is a selective agonist for a 5-HT1 -like receptor sub-type which mediates contraction of some cranial blood vessels in vitro. It has been shown to be a very effective novel agent for the acute treatment of migraine and this has stimulated much interest in its clinical mode of action. It has been suggested that the pain of migraine results from a sterile neurogenic inflammatory response of intracranial blood vessels innervated by the trigeminal nerve. Furthermore, sumatriptan has been shown to inhibit plasma protein extravasation from blood vessels of the dura mater, induced by antidromic stimulation of the trigeminal nerve in the anaesthetised rat and guinea-pig. This effect could be explained by a localised vasoconstriction of the meningeal vessels. We now provide evidence that sumatriptan will potently constrict the blood vessels within the human isolated perfused dura mater. Preliminary work on characterising the 5-HT receptor involved indicates that it is a 5-HT1- like receptor. These studies add weight to the view that the anti-migraine action of sumatriptan results from selective cranial vasoconstriction.