Mirror Chamber Test Research Articles

Potential anxiolytic therapeutics from Hybanthus enneaspermus (L.) F. Muell. - mitigate anxiety by plausibly modulating the GABAA-Cl- channel

Anxiety is a commonly prevailing psychological disorder that requires effective treatment, wherein phytopharmaceuticals and nutraceuticals could offer a desirable therapeutic profile. Hybanthus enneaspermus (L.) F. Muell. is a powerful medicinal herb, reportedly effective against several ailments, including psychological disorders. The current research envisaged evaluating the anxiolytic potential of the ethanolic extract of Hybanthus enneaspermus (EEHE) and its toluene insoluble biofraction (ITHE) employing experimental and computational approaches. Elevated Plus Maze, Light and Dark Transition, Mirror Chamber, Hole board and Open field tests were used as screening models to assess the antianxiety potential of 100, 200 and 400 mg/kg body weight of EEHE and ITHE in rats subjected to social isolation, using Diazepam as standard. The brains of rats exhibiting significant anxiolytic activity were dissected for histopathological and biochemical studies. Antioxidant enzymes like catalase, superoxide dismutase, glutathione-S-transferase, glutathione peroxidase, glutathione reductase; and neurotransmitters viz. monoamines (serotonin, noradrenaline, dopamine), Gamma-aminobutyric acid (GABA), and glutamate were quantified in the different regions of rats’ brain (cortex, hippocampus, pons, medulla oblongata, cerebellum). Chromatographic techniques were used to isolate phytoconstituents from the fraction exhibiting significant activity that were characterized by spectroscopic methods and subjected to in silico molecular docking. ITHE at 400 mg/kg body weight significantly mitigated anxiety in all the screening models (p < 0.05), reduced the inflammatory vacuoles and necrosis (p < 0.05) and potentiated the antioxidant enzymes (p < 0.05). It enhanced the monoamines and GABA levels while attenuating glutamate levels (p < 0.01) in the brain. Three significant flavonoids viz. Quercitrin, Rutin and Hesperidin were isolated from ITHE. In silico docking studies of these flavonoids revealed that the compounds exhibited substantial binding to the GABAA receptor. ITHE displayed a promising pharmacological profile in combating anxiety and modulating oxidative stress, attributing its therapeutic virtues to the flavonoids present.

Acacia catechu Willd. and Acacia arabica Willd. decrease the extent of anxiety behavior by reducing oxidative stress and moderating neurochemicals

Ethnopharmacological relevanceAnxiety is a very common psychiatric problem. It affects a large group of people in the world population. Acacia genus is well known for phenolic and flavonoid content. Literature showed its potential for various biological activities and is useful in the treatment of chest pain, asthma, bronchitis, wounds, mouth ulcer, colic, vitiligo, sore throat, inflammation, diarrhoea and also used as tonic. Aim of the studyThe present study was conducted to assess the antianxiety potential of two plants Acacia catechu Willd. and Acacia arabica Willd. from the common family Fabaceae. Materials and methodsThe stems of both plants were used for this purpose. Plants were subjected to complete exhaustive successive extraction using petroleum ether, chloroform, ethanol, and water as solvent. After pharmacognostic and phytochemical investigation, antianxiety activity was conducted on Swiss albino mice at different dose levels (100, 200, 300, & 400 mg/kg body weight p.o.) for all successive extracts of both plants. Two active extracts from each plant were further assessed for anxiolytic potential using the open-field test and mirror chamber test. One extract with the maximum response from each plant was further screened using mCPP-induced anxiety test. ResultsThe stem of ethanol extract of A. catechu showed comparable antianxiety activity at 400 mg/kg to the standard drug diazepam (2.5 mg/kg). Improved SOD, catalase, and LPO levels were noted after administration of A. catechu ethanolic extract at 400 mg/kg. ConclusionsIn conclusion, A. catechu ethanolic extract improved anxiety symptoms at dose-dependent levels in mice.

Levels of glutathione-related antioxidants in some tissues of stressed Wistar rats

Objectives: Oxidative stress (OS)-related pathologic conditions in the tissues of living organism have been linked to exposure to stressful events within the environment. This study examined the impact of different kinds of stress exposure on glutathione (GSH)-related antioxidants. The effect of stress was examined using comparative levels of GSH, glutathione-S-transferase (GST) and glutathione peroxidase (GPx) in female Wistar rats. Materials and Methods: One hundred and sixty-eight adult female Wistar rats with body weights ranging between 150 and 200 g, were used for the study. The animals were distributed into 28 groups of six animals each. The experimental animals were routinely exposed to three different stressors; restraint chamber test, mirror chamber test and intruder chamber test for a duration of 1, 3 or 5 h per day for 1, 2 and 3 weeks, respectively. All animals were allowed free access to food (rat chaws), with water ad libitum. Animals were euthanise through cervical dislocation after the experimental period and the different target tissues were carefully harvested and homogenised for antioxidant estimation following standard procedure. Data obtained were statistically analysed and values expressed as mean ± standard error of mean and P &lt; 0.05 level was considered as statistically significant. Results: Findings from this study elucidated the fact that exposure to stress is capable of causing marked OS and reducing GSH-based antioxidant activities in Wistar rats. A decline in the GSH level and GPx activity as observed in the study is an indication of alterations of kidney and brain tissue cellular integrity by free radicals generated during exposure to the stressors, while the observed significant increase in GST activity level in the affected tissues indicates compromised rapid exhaustion of the cellular system. Conclusion: Hence, we conclude that stress of different nature, intensity and duration can alter the levels of GSH-related antioxidants, especially in the kidney, ovary and brain tissues of stressed Wistar rats. The GSH levels in liver tissues were observed not to have changed significantly despite the oxidative damage caused by the stressors.

STUDY OF THE ANXIOLYTIC ACTIVITY OF ETHANOLIC EXTRACT OF ROOT OF ACORUS CALAMUSIN ALBINO MICE USING MIRRORED CHAMBER

Objective: Anxiety is classified as a form of sub-acute or chronic fear. Root of Acorus calamus has been traditionally used as an anxiolytic. The aim of the study is to assess the anxiolytic activity of ethanolic extract of the root of Acorus calamus (EEAC) by Mirrored Chamber Test on Albino mice. Methods: Albino mice of either sex were taken and divided into five groups, each consisting of 5 mice. One group was used as control, one as standard (Diazepam) and three as test groups treated with 100, 200 &amp; 400 mg/kg of EEAC. The drugs i.e., 10 ml/kg of Normal saline for control, Diazepam 2 mg/kg (standard) and 100, 200 &amp; 400 mg/kg EEAC (test groups) were injected intraperitoneally (i.p.), 30 mins before placing them in the center of the mirrored chamber. Latency to enter the chamber, number of entries in five minutes and total time spent in the chamber during 5 minutes test period were compared in each group. Data were statistically analyzed by one-way analysis of variance followed by multiple Dunnett’s test. Results: EEAC showed significant increase in all the parameters for the doses of 100, 200 and 400 mg/kg in a dose dependent manner. Conclusion: EEAC has anxiolytic activity.

Anxiety-related defensive behavioral responses in mice selectively bred for High and Low Activity.

High and Low Activity strains of mice (displaying low and high anxiety-like behavior, respectively) with 7.8-20 fold differences in open-field activity were selected and subsequently inbred to use as a genetic model for studying anxiety-like behavior in mice (DeFries et al., 1978, Behavior Genetics, 8:3-13). These strains exhibited differences in other anxiety-related behaviors as assessed using the light-dark box, elevated plus-maze, mirror chamber, and elevated square-maze tests (Henderson et al., 2004, Behavior Genetics, 34: 267-293). The purpose of these experiments was three-fold. First, we repeated a 6-day behavioral battery using updated equipment and software to confirm the extreme differences in anxiety-like behaviors. Second, we tested novel object exploration, a measure of anxiety-like behavior that does not rely heavily on locomotion. Third, we conducted a home cage wheel running experiment to determine whether these strains differ in locomotor activity in a familiar, home cage environment. Our behavioral test battery confirmed extreme differences in multiple measures of anxiety-like behaviors. Furthermore, the novel object test demonstrated that the High Activity mice exhibited decreased anxiety-like behaviors (increased nose pokes) compared to Low Activity mice. Finally, male Low Activity mice ran nearly twice as far each day on running wheels compared to High Activity mice, while female High and Low Activity mice did not differ in wheel running. These results support the idea that the behavioral differences between High and Low Activity mice are likely to be due to anxiety-related factors and not simply generalized differences in locomotor activity.

Bioactivity-directed isolation, characterization, and quantification of an anxiolytic flavonoid from Brassica oleracea L.

Brassica oleracea L. or Broccoli, is known for its numerous health benefits attributed to the rich array of phytochemicals. Our earlier study showed the hydroalcoholic extract of Broccoli had significant antianxiety activity. The present study involved bioactivity-directed fractionation of the active extract with the aim of separating the constituent responsible for the activity. The bioactive extract was fractionated by column chromatography. The antianxiety activity of the obtained fractions and sub-fractions was evaluated using the elevated plus maze model in mice. It led to the isolation of the bioactive compound. The antianxiety effect was confirmed by hole-board test and mirror chamber test. Structure of the compound was characterized by UV, IR, 1 H NMR, 13 C NMR, MS techniques, and was found to be kaempferol-3-O-β-D-glucoside. The content of kaempferol-3-O-β-D-glucoside in florets of B. oleracea was determined by HPTLC. It was found to be present to the extent of 0.061% w/w. PRACTICAL APPLICATIONS: Anxiety disorders cause immense suffering worldwide and hence search for safe and effective antianxiety drugs has become important area of research. Most commonly and widely prescribed drugs for anxiety that is, benzodiazepines may cause many adverse effects such as drowsiness, confusion, dizziness etc. They also cause physical dependence and withdrawal symptoms. Flavonoids, and their semi-synthetic derivatives, moreover, do not cause any such side effects unlike benzodiazepines. Broccoli or Brassica oleracea is reported to contain a number of flavonoids like quercetin, kaempferol, and their derivatives. In the present investigation, bioactivity-guided isolation showed that the antianxiety activity of B. oleracea is due to kaempferol-3-O-β-D-glucoside, a compound which has been earlier reported to be present in B. oleracea. Hence, after detailed investigation this compound can be developed into a potential antianxiety drug.

Lacidipine attenuates caffeine-induced anxiety-like symptoms in mice: Role of calcium-induced oxido-nitrosative stress.

Anxiety is a disorder of multi-factorial pathogenesis involving interrelated pathways of neurotransmitters, oxidative stress and metamorphosed calcium-signaling that negatively affects brain functions. Modulation of Ca2+-channels outlines a promising strategy to curb the progression of anxiety-like disorders through attenuation of redox-imbalance. The current research scheme was designed to explore the anxiolytic effects of lacidipine (L-type Ca2+-channel blocker; LCD) pretreatment in caffeine-induced anxiety-like symptom model in mice. Forty-two Swiss albino mice (25-30 g) were distributed to 7 groups (n = 6): Vehicle control, caffeine, alprazolam + caffeine, lacidipine(0.3, 1 and 3 mg/kg, ip)+caffeine and Bay-K8644+LCD(3)+caffeine. Caffeine (25 mg/kg, ip) was administered from day 8 to 14 to induce anxiety-like symptoms in mice. Lacidipine (0.3, 1 and 3 mg/kg, ip) and alprazolam (0.25 mg/kg, ip) were administered from day 1 to 14 in separate groups. Bay-K8644 (Ca2+-channel agonist) was injected on day 14 to delineate the role of Ca2+ in anti-anxiety effect of LCD in caffeine-treated mice. Elevated zero maze and mirror chamber test were employed to assess anxiety-like behavior. Afterwards, the mice were sacrificed and whole brains were harvested for estimation of biomarkers of oxido-nitrosative stress, such as TBARS, GSH, SOD, catalase and total nitrite content. An increase in brain oxido-nitrosative stress and anxiety-like behavior was observed in caffeine treated mice. LCD pretreatment attenuated the brain oxido-nitrosative stress and anxiety-like behavior in mice in caffeine treated mice. Anxiolytic effect of LCD was attenuated by Bay-K8644 (0.5 mg/kg) in caffeine treated mice. LCD (L-type Ca2+-channel antagonist) pretreatment attenuated caffeine-induced oxido-nitrosative stress and anxiety-like behavior.

Kami-shoyo-san ameliorates sociability deficits in ovariectomized mice, a putative female model of autism spectrum disorder, via facilitating dopamine D1 and GABAA receptor functions

Ethnopharmacological relevanceKami-shoyo-san (KSS) is a Kampo formula used clinically for menopause-related symptoms in Japan. However, the effect of KSS on autism spectrum disorder (ASD), a developmental disorder with a higher prevalence in males than in females, has not been reported yet. Aim of the studyIt is accepted generally that dysfunction in the GABAergic system is associated with pathogenesis of ASD. In our previous study, a decrease in brain allopregnanolone (ALLO), a positive allosteric GABAA receptor modulator, induced ASD-like symptoms such as impaired sociability-related performance and increased repetitive self-grooming behavior in male mice, and that KSS ameliorated these behavioral abnormalities via GABAA receptor- and dopamine D1 receptor-mediated mechanisms. In this study, to better understand a gender difference in the prevalence of ASD, we examined whether dissection of ovary (OVX), a major organ secreting progesterone in females, causes ASD-like behaviors in a manner dependent on brain ALLO levels, and if so, how KSS affects the behaviors. Materials and methodsSix-week-old ICR female mice received ovariectomy, and KSS (74 mg/kg and 222 mg/kg, p.o.) were treated before 1 h starting each behavioral test. The sociability, social anxiety-like behavior, and self-grooming behavior were analyzed by the resident-intruder test, mirror chamber test, and open field test, respectively. After finishing the behavioral experiment, the ALLO content in the brain was measured by ELISA. Furthermore, we examined the effects of OVX on the neuro-signaling pathways in the prefrontal cortex and striatum by Western blotting. ResultsThe results revealed that OVX induced sociability deficits and social anxiety-related behaviors, but not repetitive self-grooming behavior, and that these behavioral changes were accompanied not only by a decrease of brain ALLO levels, but also by impairment of CREB- and CaMKIIα-mediated neuro-signaling in the prefrontal cortex. Moreover, the administration of KSS had no effect on the brain ALLO level, but significantly ameliorated the OVX-induced behavioral and neurochemical changes via facilitation of GABAA receptor and dopamine D1 receptor-mediated neurotransmission. ConclusionsThese findings suggest that a decrease in gonadal hormone-derived ALLO plays a major role in ASD-like behaviors in female mice and that KSS is beneficial for the treatment of ASD in females.

Evaluation of the protective effect of ethanolic extract of seed kernel of Caesalpinia bonducella Flem (EECB) on forced swimming-induced chronic fatigue syndrome in mice

Objective: To study the protective effect of Ethanolic extract of seed kernal of caessalpinia bonducella Flem on forced swimming-induced chronic fatigue syndrome (CFS) in mice. Materials and Methods: Male albino mice of 25–40 g were grouped into five groups taking 5 mice in each group. Group A served as naive control, Group B as stress control, and Group C and D received EECB at a dose of 200 mg/kg and 400 mg/kg, respectively. Group E was given the standard drug (imipramine 20 mg/kg). All animals received their respective agent orally daily for 7 days. Except for Group A animals, animals in all other groups were subjected to force swimming 6 min daily for 7 days to induce a state of chronic fatigue. Animals were assessed for duration of immobility on day 1, 3, 5, and 7. Level of anxiety (elevated plus maze and mirrored chamber test) and locomotor activity (open field test) were assessed 24 h after the last force swimming which was followed by estimation of oxidative biomarkers in brain homogenate. Results: Treatment with EECB (200 mg/kg and 400 mg/kg) and imipramine resulted in statistically significant (P ≤ 0.05) reduction in anxiety and duration of immobility, and there was significant increase in locomotor activity when compared to stress control group. Significant reduction in malondialdehyde level and increase in catalase level were seen in EECB and imipramine-treated group compared to stress control group. Conclusion: The study confirms that EECB has protective effect against experimentally induced CFS.

EVALUATION OF THE PROTECTIVE EFFECT OF ETHANOLIC EXTRACT OF LEAVES OF PUNICA GRANATUM LINN. ON FORCED SWIMMING INDUCED CHRONIC FATIGUE SYNDROME IN MICE

&lt;p&gt;&lt;strong&gt;Objective: &lt;/strong&gt;To study the protective effect of ethanolic extract of leaves of &lt;em&gt;Punica granatum&lt;/em&gt; Linn. (EEPG) on forced swimming induced chronic fatigue syndrome (CFS) in mice.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Methods&lt;/strong&gt;:&lt;strong&gt; &lt;/strong&gt;Male albino mice of 25-40 grams were grouped into five groups taking 5 mice in each. Group A served as naïve control, Group B as stress control, Group C and D received EEPG at a dose of 100 mg/kg and 200 mg/kg respectively. Group E was given a standard drug (Imipramine 20 mg/kg). All animals received their respective agent orally daily for 7 d. Except for group A animals, animals in all other groups were subjected to force swimming 6 min daily for 7 d to induce a state of chronic fatigue. Animals were assessed for the duration of immobility on day 1&lt;sup&gt;st&lt;/sup&gt;, 3&lt;sup&gt;rd&lt;/sup&gt;, 5&lt;sup&gt;th&lt;/sup&gt; and 7&lt;sup&gt;th&lt;/sup&gt;. Level of anxiety (elevated plus maze and mirrored chamber test) and locomotor activity (open field test) were assessed 24 h after last force swimming which was followed by estimation of oxidative biomarkers in brain homogenate.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Results&lt;/strong&gt;:&lt;strong&gt; &lt;/strong&gt;Treatment with EEPG (100 mg/kg and 200 mg/kg) and imipramine resulted in a statistically significant (p≤0.05) reduction in anxiety and duration of immobility and there was a significant increase in locomotor activity when compared to stress control group. Significant reduction in MDA level and increase in catalase level were seen in EEPG and imipramine-treated group compared to stress control group.&lt;strong&gt;&lt;/strong&gt;&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Conclusion&lt;/strong&gt;:&lt;strong&gt; &lt;/strong&gt;The study confirmed that EEPG has protective action effect against experimentally induced CFS.&lt;/p&gt;

Antianxiety activity guided isolation and characterization of bergenin from Caesalpinia digyna Rottler roots

Ethnopharmacological relevanceCaesalpinia digyna Rottler (Caesalpiniaceae) roots have been used traditionally for soothing nerves, as nervine tonic and febrifuge. The aim of the present study was to isolate the antianxiety constituent(s) from C. digyna roots following bioactivity guided fractionation approach. Material and methodsBioactive fraction F4 was subjected to column chromatography to get three sub-fractions (F4.1–F4.3) and a compound CD2. CD1 and CD2 were characterized using standard spectral techniques. Three fractions (F4.1–F4.3) were evaluated for antianxiety activity in mice using EPM. An effective dose of the antianxiety principle was optimized, and its activity was, further evaluated using open field and mirror chamber tests. ResultsCD1 and CD2 characterized as bergenin, exhibited significant antianxiety activity at 80mg/kg, po which was statistically comparable to that of diazepam (2mg/kg, po). However, F4.1-F4.3 were observed to be devoid of antianxiety activity. Bergenin also exhibited significant antianxiety activity in open field and mirrored chamber tests. ConclusionsBergenin, isolated from roots of C. digyna, exhibits significant antianxiety activity at 80mg/kg, po in three different models for evaluating antianxiety activity. This activity of bergenin is being reported for the first time.

GABA-BZD Receptor Modulating Mechanism of Panax quinquefolius against 72-h Sleep Deprivation Induced Anxiety like Behavior: Possible Roles of Oxidative Stress, Mitochondrial Dysfunction and Neuroinflammation.

Rationale: Panax quinquefolius (American Ginseng) is known for its therapeutic potential against various neurological disorders, but its plausible mechanism of action still remains undeciphered. GABA (Gamma Amino Butyric Acid) plays an important role in sleep wake cycle homeostasis. Thus, there exists rationale in exploring the GABA-ergic potential of Panax quinquefolius as neuroprotective strategy in sleep deprivation induced secondary neurological problems.Objective: The present study was designed to explore the possible GABA-ergic mechanism in the neuro-protective effect of Panax quinquefolius against 72-h sleep deprivation induced anxiety like behavior, oxidative stress, mitochondrial dysfunction, HPA-axis activation and neuroinflammation.Materials and Methods: Male laca mice were sleep deprived for 72-h by using Grid suspended over water method. Panax quinquefolius (American Ginseng 50, 100, and 200 mg/kg) was administered alone and in combination with GABA modulators (GABA Cl− channel inhibitor, GABA-benzodiazepine receptor inhibitor and GABAA agonist) for 8 days, starting 5 days prior to 72-h sleep deprivation period. Various behavioral (locomotor activity, mirror chamber test), biochemical (lipid peroxidation, reduced glutathione, catalase, nitrite levels), mitochondrial complexes, neuroinflammation marker (Tumor Necrosis Factor, TNF-alpha), serum corticosterone, and histopathological sections of brains were assessed.Results: Seventy two hours sleep deprivation significantly impaired locomotor activity, caused anxiety-like behavior, conditions of oxidative stress, alterations in mitochondrial enzyme complex activities, raised serum corticosterone levels, brain TNFα levels and led to neuroinflammation like signs in discrete brain areas as compared to naive group. Panax quinquefolius (100 and 200 mg/kg) treatment restored the behavioral, biochemical, mitochondrial, molecular and histopathological alterations. Pre-treatment of GABA Cl− channel inhibitor as well as GABA-benzodiazepine receptor inhibitor, significantly reversed the protective effect of P. quinquefolius (100 mg/kg) in 72-h sleep deprived animals (P < 0.05). However, pretreatment with GABAA agonist, potentiated Panax quinquefolius's protective effect which was significant as compared to their effect per se (p < 0.05).Conclusion: GABA-ergic mechanism could be involved in the neuroprotective effect of P.quinquefolius against sleep deprivation induced anxiety-like behavior, oxidative stress, mitochondrial dysfunction, HPA axis activation and neuroinflammation.

Exploring the Possible Mode of Anxiolytic Action of a Polyherbal Formulation in Animal Models of Anxiety

The polyherbal formulation, PH-1, containing fresh aqueous extracts of Valeriana and, Boswellia spp. as major constituents and, Plumbago, Acorus spp. as minor constituents was investigated to explore the anti-anxiolytic activity and, its mode of action through competitive GABA receptor bindings with different antagonists of known nature e.g., flumazenil, picrotoxin and bicuculine. The open field, staircase test and, mirror chamber tests of animal models of anxiety were employed at 100, 200, 400 and 800 mg/kg dose levels. The formulation exhibited significant dose dependent anxiolytic activity through oral administration for varying periods of time in different paradigms of increased time-spent in mirror chamber, in central platform of open filed and, the enhanced climbing of steps in staircase tests. The 200 and, 400 mg/kg doses were highly effective. The formulation seems to be acting through GABAA-benzodiazepine binding site as evident from the blockage of PH-1 action at 400 mg/kg dose level by the flumazenil, a known GABAA-benzodiazepine receptor antagonist, and, picrotoxin, a known GABAA receptor-chloride channel complex antagonist. However, the blockade of anxiolytic activity by bicuculine through GABAA-GABA binding receptor antagonist was not significant which also confirmed the mode of action through activation of benzodiazepine receptor and, facilitation of benzodiazepine interdependent chloride channel complex.

Possible involvement of nitric oxide mechanism in the neuroprotective effect of rutin against immobilization stress induced anxiety like behaviour, oxidative damage in mice

Dietary supplements are widely used to manage stress and related consequences. However, the exact pathological mechanism and cellular cascades involved in the action of these supplements are not properly understood so far. Therefore, the present study has been designed to explore the neuroprotective mechanism of rutin against immobilization stress-induced anxiety-like behavioural and oxidative damage in mice. Laboratory Animal Centre A-strain (laca) mice were used in the present study. Rutin (20, 40, and 80mg/kg), l-arginine (100mg/kg), l-nitroarginine methyl ester (l-NAME) (5mg/kg) and vitamin-E (50mg/kg) were administered for 5 days before 6h immobilization stress on 6th day. Various behavioural parameters (mirror chamber test, locomotor activity) followed by biochemical parameters (lipid peroxidation, nitrite concentration, reduced glutathione and catalase) in brain and then serum corticosterone level were assessed. 6h immobilization stress produced anxiety-like behavioural in mirror chamber test, raised corticosterone level and oxidative stress (as evidenced by rise in lipid peroxidation, nitrite concentration, depletion of reduced glutathione and catalase activity) significantly as compared to naive group. 5 days pre-treatment with rutin (40 and 80mg/kg) causes a significant attenuation of locomotor activity, corticosterone level, oxidative stress as compared to control. Further, l-arginine (100mg/kg) pre-treatment significantly reversed the protective effect of rutin (40mg/kg) in 6h immobilized animals. However, l-NAME (5mg/kg) pre-treatment with rutin (40mg/kg) potentiated their protective effect which was significant as compared to their effect per se. The present study suggests the involvement of nitric oxide mechanism in the neuroprotective effect of rutin against immobilization stress-induced anxiety-like behaviour and oxidative damage in mice.

Association between serum cholesterol, brain serotonin, and anxiety: A study in simvastatin administered experimental animals

Introduction: The present research was designed to investigate the association between serum cholesterol, brain serotonin, and anxiety in simvastatin administered experimental animals. Materials and Methods: Both mice and rats were used for the study. Simvastatin (50 and 100 mg/kg in rats and 70 and 140 mg/kg in mice) was administered orally for one month. Serum cholesterol and brain serotonin levels were monitored. Two behavioral models, elevated plus maze test and mirrored chamber test were used to evaluate anxiety in the animals. Results: Simvastatin caused a significant reduction ( P Conclusion: Hence these experimental results have established the pharmacological evidence to the hypothesis for the relation between serum cholesterol, brain serotonin, and symptoms of anxiety and also confirm that long-term administration of lipophilic statins can lead to anxiety.

Evaluation of sesamol and buspirone in stress induced anxiety in mice

Objectives:The present study was designed to elucidate the effects of sesamol, buspirone and their combination in immobilization stress induced behavioral and biochemical alterations in mice.Materials and Methods:Male Laca mice (divided into 10 groups with 6 animals each) were pre-treated with sesamol (5 and 10 mg/kg; p.o.), buspirone (5 and 10 mg/kg; p.o.) and combination of sesamol (5 and 10 mg/kg; p.o.) with buspirone (5 mg/kg; p.o.) for consecutive five days. On the 6th day, animals were immobilized for 6 h and various behavioral tests such as body weight, locomotor activity, mirror chamber test and elevated plus maze were carried out. Biochemical estimations such as lipid peroxidation and nitrite concentration, glutathione and catalase levels were done. Data was analyzed using One way ANOVA followed by Tukey's test (P < 0.05) was considered statistical significant.Results:Immobilization stress significantly (P < 0.05) impaired body weight, locomotor activity, induced anxiety like behavioral and oxidative damage as compared to naοve animal. Pretreatment with sesamol (5 and 10 mg/kg; p.o.) and buspirone (5 and 10 mg/ kg; p.o.) significantly (P < 0.05) improved body weight, locomotor activity, and anxiety like behavior in mirror chamber as well as plus maze performance tasks and anti-oxidant like effect as evidenced by reduced lipid peroxidation, nitrite concentration and restoration of reduced glutathione and catalase activity as compared to control animals. Further, co- administration of sesamol (5 and 10 mg/kg) with buspirone (5 mg/kg) significantly (P < .05) potentiated the anti anxiety effects as compared to their effects alone.Conclusions:The present study suggests that combination of sesamol and buspirone potentiated the antianxiety effects against anxiety induced by immobilization stress and oxidative damage in mice.

Nitric oxide modulation in protective role of antidepressants against chronic fatigue syndrome in mice

Background and Objective:The present study was designed to elucidate the possible nitric oxide (NO) mechanism in the protective effect of antidepressants using mice model of chronic fatigue syndrome (CFS).Materials and Methods:Male albino laca mice were forced to swim for each 6 min session for 7 days and immobility period was measured on every alternate day (1st, 3rd, 5th, 7th). After 7 days various behavioral tests (locomotor, mirror chamber, and plus maze tests for anxiety) were performed and biochemical estimations (lipid peroxidation, nitrite levels, GSH (reduced glutathione), and catalase activity) in mice brain were performed. Animals were pretreated with citalopram (5 and 10 mg/kg) and imipramine (10 and 20 mg/kg) daily for 7 days.Results:The present study showed that continued forced swimming for 7 days caused chronic fatigue-induced anxiety-like behavior as assessed in mirror chamber, plus maze tests, and impairment in locomotor activity followed by oxidative damage (as evidenced by increased lipid peroxidation, nitrite levels, depleted reduced glutathione, and catalase activity) in animals. Seven days pretreatment with citalopram (5 and 10 mg/kg) and imipramine (10 and 20 mg/kg) significantly improved behavioral and biochemical alterations. Further, L-nitro-arginine methyl ester (L-NAME,5 mg/kg) and methylene blue (MB, 10 mg/kg) pretreatment with citalopram (5 mg/kg) or imipramine (10 mg/kg) potentiated their protective effect. However, l-arginine (100 mg/kg) pretreatment with citalopram (5 mg/kg) or imipramine (10 mg/kg) reversed their protective effect as compared with their effect per se (P < 0.05).Conclusion:The present study suggests that protective effect of citalopram and imipramine might be due to its NO modulation against chronic fatigue induced behavioral and biochemical alterations.

Comparison of the predictive validity of the mirror chamber and elevated plus maze tests in mice

The mirror chamber (MC) is a putative test of anxiety-like behavior in mice, and is increasingly popular. Nonetheless, it is unclear whether the observed behaviors rely on the presence of mirrored panels. If so, it is unclear whether the behaviors are sensitive to clinically effective anxiolytics, and how the test compares to the elevated plus maze (EPM) in terms of predictive validity. The present studies assessed anxiety-like behaviors in different mouse strains in the MC using mirrored and non-mirrored panels, under variable lighting conditions. We also assessed the pharmacological validity of the MC and EPM tests, and the locomotor properties of active test compounds. Seven mouse strains exhibited different levels of anxiety-like behaviors in the MC, and differential sensitivity to panel and light conditions. DBA/2J mice appeared most sensitive to the mirrored, versus black or white, panels and were therefore used in pharmacological MC studies. The mGlu5 receptor antagonist MPEP significantly decreased anxiety-like behaviors, similar to an intermediate dose of the benzodiazepine diazepam. The benzodiazepines chlordiazepoxide and alprazolam and the 5HT1A partial agonist buspirone had no effects on anxiety-like behaviors in the MC. None of the MC effects of active test compounds were attributable to non-specific/locomotor effects. The antidepressants fluoxetine and venlafaxine increased anxiety-like behaviors in the MC. By contrast, the anxiolytic-like effects of chlordiazepoxide, diazepam and MPEP were revealed in the EPM in C57Bl6/J mice. In conclusion, the EPM test exhibits superior predictive validity compared to the MC test, despite the sensitivity of the MC to mouse strain differences.

Venlafaxine involves nitric oxide modulatory mechanism in experimental model of chronic behavior despair in mice

Present study has been designed to elucidate the nitric oxide modulatory mechanism of venlafaxine in experimental model of chronic behavior despair in mice. Animals (male albino laca mice) were forced to swim daily for 6 min test session for 7 days and immobility period of each animal was measured on every alternate days. Six minutes forced swimming test session for 7 days caused anxiety-like behavior (as assessed by mirror chamber and plus maze tests) and impairment in locomotor activity followed by oxidative damage (increased lipid peroxidation, nitrite concentration, depleted reduced glutathione and catalase activity) as compared to naïve animals. Seven days venlafaxine (5 and 10 mg/kg) treatment significantly caused anti-anxiety-like effect, improved locomotor activity and attenuated oxidative damage (reduced lipid peroxidation, nitrite concentration and caused restoration of reduce glutathione and catalase activity) as compared to control. Caffeine (10 mg/kg) pretreatment with venlfaxine (5 mg/kg) did not produce any significant effect on locomotor activity, immobility period and oxidative damage as compared to their effect per se. Further, l-NAME (5 mg/kg) and methylene blue (10 mg/kg) pretreatment with sub effective dose of venlafaxine (5 mg/kg) potentiated its protective effect which was significant as compared to their effect per se. However, l-arginine (100 mg/kg) pretreatment with venlafaxine (5 mg/kg) significantly reversed the protective effect of venlafaxine ( P < 0.05). Present study suggests that nitric oxide modulation might be involved in the protective effects of venlafaxine.

Protective effects of antidepressants against chronic fatigue syndrome – induced behavioral changes and biochemical alterations

Chronic fatigue syndrome (CFS) is characterized by profound fatigue, which substantially interferes with daily activities. The aim of this study was to explore the protective effects of antidepressants in an animal model of CFS in mice. Male albino mice were forced to swim individually for a period of 6-min session each for 7 days. Imipramine (10 and 20 mg/kg), desipramine (10 and 20 mg/kg) and citalopram (5 and 10 mg/kg) were administered 30 min before forced swimming test on each day. Various behavior tests (immobility time, locomotor activity, anxiety-like behavior by plus maze and mirror chamber) followed by biochemical parameters (lipid peroxidation, reduced glutathione, catalase and nitrite level) were assessed in chronic stressed mice. Chronic forced swimming for 7 days significantly caused increase in immobility period, impairment in locomotor activity, anxiety-like behavior, and oxidative stress (raised lipid peroxidation, nitrite activity and reduced glutathione and catalase activity) as compared with naïve mice (P < 0.05). Seven days of pretreatment with imipramine (10 and 20 mg/kg), desipramine (10 and 20 mg/kg), and citalopram (5 and 10 mg/kg) significantly reduced immobility time, improved locomotor activity and anti-anxiety effect (in both plus maze and mirror chamber test), and attenuated oxidative stress in chronic stressed mice as compared with control (chronic fatigues) (P < 0.05). These results suggested that these drugs have protective effect and could be used in the management of chronic fatigue like conditions.