Head Dips Research Articles

Psychopharmacological properties of saponins from Randia nilotica stem bark

Context: Decoctions of Randia nilotica Stapf. (Rubiaceae) have been used in the Nigerian traditional medicine for the management of epilepsy, anxiety, depression and psychosis for many years and their efficacies are widely acclaimed among the rural communities of Northern Nigeria.Objective: The aim of this study is to establish whether the saponins present in R. nilotica are responsible for its acclaimed beneficial effects in Nigerian traditional medicine.Materials and methods: The behavioural properties of the saponin-rich fraction (SFRN) of R. nilotica stem bark were studied on hole-board, diazepam-induced sleep, rota-rod and beam-walking in mice. The anticonvulsant properties of SFRN were also examined on maximal electroshock, pentylenetetrazole- and strychnine-induced seizures in mice.Results: The intraperitoneal LD50 of SFRN in mice and rats were estimated to be 11.1 and 70.7 mg/kg, respectively. SFRN significantly prolonged the duration of diazepam-induced sleep; diminished head dip counts in the hole-board test and protected mice against maximal electroshock seizures. SFRN failed to protect mice against pentylenetetrazole- and strychnine-induced seizures; and had no effect on motor coordination on the rota-rod treadmill at the doses tested. SFRN significantly decreased the number of foot slips in the beam-walking assay in mice with no effect on time to reach the goal box.Discussion and conclusion: This study provides evidence of the psychopharmacological effects of SFRN, thus supporting further development of the psychoactive components as remedies for epilepsy.

Effect of Cissampelos Pareira Leaves on Anxiety-like Behavior in Experimental Animals

The present study was undertaken to evaluate anxiolytic effect of 70% hydroethanolic extract of leaves of Cissampelos pareira in murine models. C. pareira (Menispermaceae) is rich in alkaloids, and phytochemical results showed that it contains alkaloids, flavanoids, terpenoids, steroids, etc., Anxiolytic activity was evaluated by using elevated plus maze test (EPM), light dark (LandD) model, and forced swim test (FS) models in rats. The efficacy of extract (100, 200, 400 mg/kg) was compared with control as well as standard diazepam (DZ; 2 mg/kg, p.o.) in EPM, LandD model, and imipramine (IM; 2.5 mg/kg, p.o.) in FS model. The results showed that DZ and extract significantly increased the number of entries, time spent in open arm, head dip counts, and rearing time, while they decreased fecal count in EPM. DZ and extract also significantly increased the number of crossings and time spent in light compartment, while they decreased duration of immobility in LandD model. In case of FS model, IM and extract significantly increased mobility and swimming time. Thus, the results confirm that hydroethanolic extract of C. pareira has the potential to be used in the management of anxiety-like behavior in a dose of 200 and 400 mg/kg. Further study is required to explore the plant and its parts for anxiolytic potential.

Maternal Separation during Breastfeeding Induces Gender-Dependent Changes in Anxiety and the GABA-A Receptor Alpha-Subunit in Adult Wistar Rats

Different models of rodent maternal separation (MS) have been used to investigate long-term neurobiological and behavioral changes, associated with early stress. However, few studies have involved the analysis of sex-related differences in central anxiety modulation. This study investigated whether MS during breastfeeding affected adult males and females in terms of anxiety and brain GABA-A receptor-alpha-subunit immunoreactivity. The brain areas analyzed were the amygdale (AM), hippocampus (HP), medial prefrontal cortex (mPFC), medial preoptic area (POA) and paraventricular nucleus (PVN). Rats were housed under a reversed light/dark cycle (lights off at 7∶00 h) with access to water and food ad libitum. Animals underwent MS twice daily during the dark cycle from postnatal day 1 to postnatal day 21. Behavior was tested when rats were 65–70 days old using the elevated plus maze and after brains were treated for immunohistochemistry. We found that separated females spent more time in the open arms and showed more head dipping behavior compared with controls. The separated males spent more time in the center of the maze and engaged in more stretching behavior than the controls. Immunohistochemistry showed that separated females had less immunostained cells in the HP, mPFC, PVN and POA, while separated males had fewer immunolabeled cells in the PFC, PVN and AM. These results could indicate that MS has gender-specific effects on anxiety behaviors and that these effects are likely related to developmental alterations involving GABA-A neurotransmission.

Effect of long-term aspartame (artificial sweetener) on anxiety, locomotor activity and emotionality behavior in Wistar Albino rats

The focus of the study is to investigate whether the long-term (90days) oral administration of aspartame (75mg/kg) has an effect in the anxiety, locomotor activity and emotionality behavior of Wistar strain male Albino rats. Aspartame releases methanol as one of its metabolites during metabolism. To mimic the human methanol metabolism, the methotrexate (MTX)-treated folate-deficient rats were used. Aspartame was administered orally to the MTX-treated animals and was studied along with controls and MTX-treated controls. The locomotor activity and emotionality behavior in the MTX-treated animals did not differ from the controls. However, the aspartame-treated MTX animals showed a marked increase in the immobilization, fecal bolus with a marked decrease in ambulation (peripheral square and central square), rearing, grooming from the control as well the MTX-treated animals. The anxiety state behavior in the MTX-treated animals did not differ from the controls. However, the aspartame-treated MTX animals showed a marked decrease in the number of open arm entry, percentage of open arm entry, time spent in open arm, percentage of time spent in open arm and number of head dips from the control as well the MTX-treated animals. It is relevant to point out that methanol released by aspartame may add an effect in the brain and that could be the additional contributing factor for the observed changes in the locomotor and their anxiety levels. This study intends to substantiate that long-term aspartame consumption can alter the behavior.

Subthalamic nucleus modulates social and anxogenic-like behaviors

In Parkinson's disease, global social maladjustment and anxiety are frequent after subthalamic nucleus (STN) stimulation and are generally considered to be linked with sociofamilial alterations induced by the motor effects of stimulation. We hypothesized that the STN is per se involved in these changes and aimed to explore the role of STN in social and anxogenic-like behaviors using an animal model.Nineteen male Wistar rats with bilateral lesions of the STN were compared with 26 sham-lesioned rats by synchronizing an ethological approach based upon direct observation of social behaviors and a standardized approach, the elevated plus maze (EPM). Comparisons between groups were performed by a Mann–Whitney–Wilcoxon test.Lesioned rats showed impairments in their social (P=0.05) and aggressive behaviors with a diminution of attacking (P=0.04) and chasing (P=0.06). In the EPM, concerning the open arms, the percentage of distance, time, inactive time, and entry were significantly decreased in lesioned rats (P=0.02, P=0.01, P=0.04, and P=0.05). The time spent in non-protected head dips was also diminished in the lesioned rats (P=0.01).These results strongly implicate the STN in social behavior and anxogenic-like behavior. In human, as DBS induces changes in the underlying dynamics of the stimulated brain networks, it could create an abnormal brain state in which anxiety and social behavior are altered. These results highlight another level of complexity of the behavioral changes after stimulation.

Bupropion induced changes in exploratory and anxiety-like behaviour in NMRI male mice depends on the age

The aim of this study was to assess the effects of the antidepressant bupropion on anxiety and novelty-seeking in adolescent mice of different ages and adults. Behavioural differences between early adolescent, late adolescent and adult NMRI mice were measured both in the elevated plus-maze and the hole-board tasks following acute administration of bupropion (5, 10, 15, 20mg/kg) or saline. In the plus maze test, early and late adolescent mice treated with bupropion (10, 15mg/kg, respectively) had lower percentages of entries in the open-arms compared to their vehicle controls. Adult mice treated with bupropion did not differ from their vehicle controls. These results suggest that the effect of this drug on anxiety-like behaviour in mice depends on the age, showing adolescents an anxiogenic-like profile. In the hole-board, adolescents showed more elevated levels of novelty-seeking than adults, exhibiting shorter latency to the first head-dip (HD) and a higher number of HD's. Bupropion increases the latency to the first HD and decreases the number of HD's in all age-groups, indicating a decline in exploratory tendency. Findings reveal that the age can modulate the behaviour displayed by mice in both animal models, and that adolescents are more sensitive to bupropion's anxiogenic effects.

Anxiogenic-like effect induced by TRPV1 receptor activation within the dorsal periaqueductal gray matter in mice

Pharmacological manipulation of TRPV1 (Transient Receptor Potential Vanilloid type-1) receptors has been emerging as a novel target in the investigation of anxiety states. Here, we attempt to show the role played by the TRPV1 receptors within the dorsal periaqueductal gray matter (dPAG), a midbrain structure strongly involved in the modulation of anxiety. Anxiety was assessed by recording spatiotemporal [percent open arm entries (%OE) and percent open arm time (%OT)] and ethological [e.g., head dipping (HD), stretched-attend postures (SAP)] measures in mice exposed to the elevated plus-maze (EPM). Mice received an intra-dPAG injection of the TRPV1 agonist capsaicin (0, 0.01, 0.1 or 1.0nmol/0.2μL; Experiment 1) or antagonist capsazepine (0, 10, 30 or 60nmol/0.2μL; Experiment 2), or combined injections of capsazepine (30nmol) and capsaicin (1.0nmol) (Experiment 3), and were exposed to the EPM to record spatiotemporal and ethological measures. While capsaicin produced an anxiogenic-like effect (it reduced %OE and %OT and frequency of SAP and HD in the open arms), capsazepine did not change any behavior in the EPM. However, when injected before capsaicin (1.0nmol), intra-dPAG capsazepine (30nmol–a dose devoid of intrinsic effects) antagonized completely the anxiogenic-like effect of the TRPV1 agonist. These results suggest that the anxiogenic-like effect produced by capsaicin is primarily due to TRPV1 activation within the dPAG in mice, but that dPAG TRPV1 receptors do not exert a tonic control over defensive behavior in mice exposed to the EPM.

Anti-anxiety activity of Stachys tibetica Vatke

AimS. tibetica Vatke is a herb distributed in the tropical and subtropical regions of the world, including Tibet, China, and India. In India it is found in the cold desert regions of Kargil, Ladakh Valley, and in the mountains of Himachal Pradesh. The traditional practitioners in the Kargil and Ladakh use the natural medicine Stachys tibetica for the treatment of various mental disorders and phobias. The present study is aimed at evaluating the anxiolytic effects of the methanolic extract of the root, stem, leaf, and whole plant material of Stachys tibetica Vatke in rats. MethodsPowdered materials (1 kg) of each plant part were subjected to extraction in a Soxhlet apparatus with methanol (95%); to yield 12.8%, 8.3%, 17.2%, and 19.6% W/W extractives, respectively. Extracts were evaluated for their anxiolytic effects using the elevated plus maze (EPM) test in rats. ResultsIn the present study, it was found that the methanolic extracts (200 and 400 mg·kg−1) of the root, stem, leaf and whole plant of Stachys tibetica Vatke and diazepam (DZ) increased the time spent and the number of entries in the open arm significantly (**P < 0.01), while they decreased the time spent and the number of entries in the closed arm. At the same time, all of the extracts and DZ decreased the time spent at the center of the maze (latency), along with closed arm returns. The head dip counts increased significantly in the rats treated with DZ, SMR400, SML400 and SMW400 in the open arm of EPM, which was a sign of reduction anxiety. The DZ and SMW did not show the fecal bolus, while other groups had reduced fecal bolus (**P < 0.01) as compared to control. These allied parameters helped to assess the anxiolytic potential of Stachys tibetica Vatke. Whole plant and leaf materials have shown the maximum activity, the root intermediate while the stem had the least anxiolytic activity (*P < 0.05, **P < 0.01) in EPM. ConclusionThe results strongly justify the use of this plant for the treatment of anxiety. Further studies are in progress in this laboratory to isolate and identify the components responsible for the anxiolytic activity and the mechanism of action involved.

EVALUATION OF NEUROPHARMACOLOGICAL, ANTIBACTERIAL AND ANTINOCICEPTIVE ACTIVITY OF METHANOLIC EXTRACT OF THE BARK OF CYNOMETRA RAMIFLORA LINN. (LEGUMINOSAE)

The crude methanolic extract of the bark of Cynometra ramiflora Linn . (Leguminosae) growing in southeast part of Bangladesh has been evaluated for its poss ible neuropharmacological, antibacterial and antinociceptive properties. The extract of Cynometra ramiflora bark potentiated the pentobarbital induced sleeping time in mice, decreased the open field score in open field test, decreased the number of hole cr ossed from one chamber in the hole cross test and decreased the head dip responses in hole board test. Acute toxicity test showed that the plant mig ht be safe for pharmacological uses. Antibacterial activity of Cynometra ramiflora bark was tested by disk d iffusion method. The extract exhibited significant antibacterial activity against Vibrio cholerae , Salmonella typhi , Staphylococcus aureus and exhibited moderate antibacterial activity against Escherichia coli, Shigella dysenteriae, Shigella sonnei, Entero cocci, Shigella boydii, Shigella flexneri, Staphylococcus epidermis. The m ethanolic extract exhibited statistically significant writhing inhibition in acetic acid - induced writhing model in white albino mice. The crude extract produced 48.62 % inhibition of writhing at the dose of 250 mg/kg body weight and 63.89 % inhibition of writhing at the dose of 500 mg/kg body weight, while the standard drug Diclofenac - Na inhibition was found to produce 69.45 % at a dose of 25 mg/kg body weight.

The Effects of N-Methyl-d-Aspartate Receptor Blockade During The Early Neurodevelopmental Period on Emotional Behaviors and Cognitive Functions of Adolescent Wistar Rats

The N-Methyl-D-Aspartate (NMDA) receptor is expressed abundantly in the brain and plays an important role in neuronal development, learning and memory, neurodegenerative diseases, and neurogenesis. In this study, we evaluated the effects of NMDA receptor blockade during the early neurodevelopmental period on exploratory locomotion, anxiety-like behaviors and cognitive functions of adolescent Wistar rats. NMDA receptor hypofunction was induced 7-10 days after birth using MK-801 in rats (0.25 mg/kg twice a day for 4 days via intraperitoneal injection). The open-field (OF), elevated plus maze (EPM) and passive avoidance (PA) tests were used to evaluate exploratory locomotion, anxiety-like behaviors and cognitive functions. In the OF test, MK-801 caused an increase in locomotion behavior (p < 0.01) and in the frequency of rearing (p < 0.05). In the EPM test, MK-801 treatment increased the time spent in the open arms, the number of open arm entries and the amount of head dipping (p < 0.01). MK-801 treatment caused no statistical difference compared to the control group in the PA test (p > 0.05). Chronic NMDA receptor blockade during the critical period of maturation for the glutamatergic brain system (postnatal days 7-10) produces locomotor hyperactivity and decreased anxiety levels, but has no significant main effect on cognitive function during adolescence.

Ethopharmacological analysis of the open elevated plus-maze in mice

Exposure of rodents to an open elevated plus-maze (oEPM) elicits antinociception and increases plasma corticosterone levels. However, no studies have yet assessed the defensive behaviour repertoire of animals in this modified test. In Experiment 1, factor analysis was employed to characterise the behavioural profile of mice exposed to the oEPM. Experiments 2 and 3 assessed the effects of acute alprazolam (0.5–1.5mg/kg; diazepam 0.5–1.5mg/kg), pentylenetetrazole (10.0–30.0mg/kg), yohimbine (2.0–6.0mg/kg), mCPP (0.3–3.0mg/kg), and acute and chronic fluoxetine (10.0–30.0mg/kg) and imipramine (1.0–15.0mg/kg) on behaviours identified in Experiment 1. The factor analyses revealed that behaviour in the oEPM can largely (77% total variance) be accounted for in terms of 3 factors: factor 1 (‘depth exploration’; e.g. head-dipping on the arms), factor 2 (‘cautious exploration of arms’; e.g. flatback approach), and factor 3 (‘risk assessment’; stretched attend postures – SAP). Experiments 2 and 3 showed that, over the dose range used, alprazolam selectively attenuated all measures of defensiveness. Similar, though more modest, effects were seen with diazepam. Confirming the intensity of the emotional response to the oEPM (nociceptive, endocrine and behavioural), relatively few significant behavioural changes were seen in response to the anxiogenic compounds tested. Although acute fluoxetine or imipramine treatment failed to modify behaviour in the oEPM, chronic fluoxetine (but not chronic imipramine) attenuated total flat back approach and increased head dipping outside the central square. Together, the results indicate that the oEPM induces behavioural defensive responses that are sensitive to alprazolam and chronic fluoxetine.

Anxiolytic and sedative properties of hydroethanolic extract of Telfairia occidentalis leaves in mice

Telfairia occidentalis Hook. f., Cucurbitaceae, is a leafy vegetable used in soup and folk medicine in southern Nigeria. This study was conducted to investigate the anxiolytic and sedative activities of the hydroethanolic extract of the leaves of T. occidentalis in mice. The hole-board, elevated plus maze, open-field, light-dark, and social interaction tests were used in this study. T. occidentalis (50-400mg/ kg) and diazepam (1mg/kg) were administered p.o. to different groups of mice and appropriate observations were made. T. occidentalis increased the number of sectional crossings (p<0.01) and duration of head dips (p<0.05) at doses of 50 and 100mg/kg respectively; increased number of entries into open arms (p<0.01) at the dose of 100mg/kg; increased number of central squares crossed (p<0.01) at the dose of 50mg/kg; and increased number of social interactions (p<0.001) at doses of 50 and 100mg/kg. At the dose of 400mg/kg, T. occidentalis reduced number of head dips and sectional crossings (p<0.01); reduced time spent in open arms and increased time spent in closed arms (p<0.01, 0.001) at doses of 200 and 400mg/ kg; reduced number of assisted rearings (p<0.001) at doses of 200 and 400mg/kg; increased latency of entry into and time spent in dark box (p<0.01, 0.001) at doses of 200 and 400mg/kg; and reduced number of social interactions (p<0.001) at the dose of 400mg/kg. The findings in this study suggest that T. occidentalis possess anxiolytic property at doses of 50 and 100mg/kg, and sedative activity at doses of 200 and 400mg/kg.

ANXIOLYTIC AND MEMORY ENHANCING ACTIVITY OF L.SICERARIA IN RODENTS

Background and objective: Lagenaria siceraria (Bottle gourd) is an important fruit vegetable grown in warm-season. Different diseases have been managed with Lagenaria siceraria in different systems of traditional medication . The plant contains various phytochemicals of pharmacological significance. In the current study, neuropharmacological screening of the plant is performed to further explore this wonderful herbal drug. Materials and Methods: Aqueous extract of Lagenaria siceraria was given orally in the dose of 200 mg/kg bid (twice a day) for a period of 30 days in mice and 45 days in rats. The head dip test and the light/dark box test were used to study anxiolytic activity while the water maze and the stationary rod were used for the assessment of memory enhancing effect. The exploratory and locomotor activities were also studied using cage crossing and open field test. All values were compared with control by taking mean of all of them and the significance of difference between mean is determined by student t-test. Values of P 0.05 were considered as significant. Results: The percentage of time spent in light box was increased to highly significant extent and the time taken to reach the plateform in stationary rod activity and water maze was significantly reduced after the administration of the drug. The exploratory and locomotor activities were also decreased.7 Conclusion: On the basis of above observations it is concluded that aqueous extract of Lagenaria siceraria possesses both anxiolytic and memory enhancing activity.

Synthetic retinoid Am80 results in improved exploratory and emotional behavior in the P8 substrain of senescence-accelerated mice

Am80 is a synthetic retinoid that has been used clinically for patients with acute promyelocytic leukemia and has been reported to affect the brain and its neurons. We investigated the influence of Am80 on anti-anxiety-like behavior, which is a characteristic of age-associated emotional disorder, in the P8 strain of senescence-accelerated mice (SAMP8). Am80 at a concentration of 2mg/kg/day was administered to the mice in their feed for 1.5months. In open-field and hole-board tests, the number of ambulation, rearing, and head dipping actions, as well as the distance moved were significantly decreased in Am80-treated SAMP8 compared with untreated SAMP8. In the light/dark box test, the latencies for the first exit were significantly increased in the Am80-treated SAMP8 compared with the untreated SAMP8. Immunohistochemical analysis revealed that the area of serotonin transporter-positive immunoreactivity in the coronal sections of the forebrain of the Am80-treated SAMP8 was increased compared with the untreated SAMP8. Furthermore, the metabolic turnovers of serotonin and dopamine were increased in the amygdalae of the SAMP8 by Am80 treatment. Thus, in the present study, Am80 was found to improve exploratory and emotional behavior in SAMP8, suggesting that Am80 regulates monoamines directly or indirectly in this senescence-accelerated model.

Locomotor and Exploratory Behaviour in Mice with Treated Oral Artemether Suspension

Previous studies with intramuscular Artemether reveal dose dependent neurotoxicity with specific concern on the nuclei of the brain stem. This study was aimed at assessing the effect of oral Artemether suspension on locomotor and exploratory behaviour in mice. The study was conducted using a total of 30 mice randomly divided into 3 groups. Group 1 served as the control and was administered with neither drug nor placebo. Groups 2 and 3 were administered with 30mg/kg/day (low dose) and 60mg/kg/day (high dose) respectively of oral Artemether suspension for 17 days. Behavioural tools used were Open Field Maze, ElevatedPlus maze and Light/Dark transition box. Parameters measured were centre square duration/ entries, frequency of rearing, frequency of line crosses, open arm duration / entries and head dips. In the Open Field test, centre square duration and entries were significantly higher in the low dose group but lower in the high dose group compared to the control. The frequency of line crosses in the Open Field test was also significantly lower in the high dose group compared to control. The frequency of rearing was significantly lower in high dose group compared to the control in all the 3 behavioural tools used. There was no significant difference between the control and the experimental mice in the frequency of head dips and open arm duration/entries. In conclusion, oral Artemether causes reduce exploratory and locomotor activity.

Neuro-pharmacological evaluation of structurally novel 5-hydroxytryptamine type 3 receptor antagonist, N-n-propyl-3-ethoxyquinoxaline-2-carboxamide (6n) for its anxiolytic potential

Aim: The present study was designed to investigate the anxiolytic activity of N-n-propyl-3-ethoxyquinoxaline-2-carboxamide (6n), a novel 5-hydroxytryptamine Type 3 (5-HT 3 ) receptor antagonist in experimental mouse models of anxiety. Materials and Methods: The anxiolytic activity of 6n (1 and 2 mg/kg, intraperitoneally (i.p.)) was evaluated in mice by using a battery of behavioral tests of anxiety such as elevated plus maze (EPM), light/dark (L and D) box, hole board (HB) and open field test (OFT) with diazepam (2 mg/kg, i.p.) as standard anxiolytic. All the tested doses of 6n did not affect the base line locomotion. Results: The new chemical entity 6n (1 and 2 mg/kg, i.p.) and diazepam (2 mg/kg, i.p.) significantly increased the percentage of time spent and number of entries in open arm in the EPM test. In the L and D test compound 6n (1 and 2 mg/kg, i.p.) and diazepam (2 mg/kg, i.p.) significantly increased the total time spent in light compartment as well as the number of transitions from one compartment to other. While 6n (2 mg/kg, i.p.), diazepam (2 mg/kg) showed a significant increase in number of square crossed and 6n at (1 mg/kg, i.p.) did not affect the number of square crossed significantly. Compound 6n (1 and 2 mg/kg, i.p.) and diazepam (2 mg/kg, i.p.) also significantly increased number of head dips and number of square crossed in HB test whereas significantly decreased the head dipping latency as compared with vehicle control group. In addition, 6n (1 and 2 mg diazepam (2 mg/kg, i.p.) significantly increased the ambulation scores and number of rearing in OFT. Conclusion: In conclusion, these findings indicated that compound 6n exhibited an anxiolytic-like effect in animal models of anxiety.

Anxiolytic-like effect of (4-benzylpiperazin-1-yl)(3-methoxyquinoxalin-2-yl)methanone (6g) in experimental mouse models of anxiety

Aim:The present study was designed to investigate the anxiolytic activity of 6g, a novel serotonin type-3 receptor (5-HT3) receptor antagonist in experimental mouse models of anxiety.Materials and Methods:The anxiolytic activity of “6g” (1 and 2 mg/kg, intraperitoneally [i.p.]) was evaluated in mice by using a battery of behavioral tests of anxiety such as elevated plus maze (EPM), light-dark (L&D) box, hole board (HB), and open field test (OFT) with diazepam (2 mg/kg, i.p.) as standard anxiolytic. None of the tested dose of “6g” affects the base line locomotion.Results:The new chemical entity “6g” (2 mg/kg, i.p.) and diazepam (2 mg/kg, i.p.) significantly (P < 0.05) increased the percentage of time spent and number of entries in open arm in the EPM test. In the L&D test compound “6g” (2 mg/kg, i.p.) and diazepam (2 mg/kg, i.p.) significantly (P < 0.05) increased the total time spent in light compartment as well as number of transitions from one compartment to other. Compound “6g” (1 and 2 mg/kg, i.p.) and diazepam (2 mg/kg, i.p.) also significantly (P < 0.05) increased number of head dips, whereas significantly (P < 0.05) decreased the head dipping latency in HB test as compared to vehicle control group. In addition, 6g (2 mg/kg, i.p.) and diazepam (2 mg/kg, i.p.) significantly (P < 0.05) increased the ambulation scores (square crossed) in OFT and there was no significant effect of 6g (1 and 2 mg/kg, i.p.) and diazepam (2 mg/kg, i.p.) on rearing scores.Conclusion:In conclusion, these findings indicated that compound “6g” exhibited an anxiolytic-like effect in animal models of anxiety.

Buspirone Ameliorates the Morphine Withdrawal-Induced Anxiety through Synaptic Ultrastructural Changes in Hippocampus of Rat

Morphine administration causes long-lasting neural changes in the brain that underpin the behavioral abnormalities, and the relationship between structural changes and behavioral symptoms is obscure. In present study, the elevated plus-maze and transmission electron microscope were applied to validate the anxiety-like behaviors and synaptic ultrastructural changes in the hippocampi of rats among the morphine group (morphine administration only), the buspirone group (morphine plus buspirone administration) and the vehicle (saline treated only). As compared with the vehicle group, lower values of OE (times of entering into the open arms), OE% (percentage of entries into the open arms), OT (time spent in the open arms), OT% (percentage of time stayed in the open arms), Ns (surface density (Sv)/numerical density (Nv)) and S (surface area) of synapses were observed in the morphine group , but significantly, behavior higher scores of RR (rearing), HD (head-dipping), FBA (flat back approach), and higher Nv, Sv, PSD (postsynaptic density), LPT (length of postsynaptic thickening), WCJ (widths in synaptic cleft on junctions) and CCR (curvature of the cleft region) of synapses appeared in the morphine group. However, no significant differences in values of most of those parameters above were detected between the vehicle group and the buspirone group. These results supported that anxiety-like symptoms of rats significantly occurred to the rats after acute morphine withdrawal, but buspirone administration could reverse these indexes. It also proved that the appearance/disappearance of anxiety-related symptoms was related to the ultrastructural changes/reversibility of synapses in the hippocampus with morphine and buspirone administrations. So, it suggested that anxiety-related symptoms were modified in rats subjected to the synaptic ultrastructural changes in hippocampus by morphine acute withdrawal and were further rehabilitated by buspirone administration. It is helpful to pursue the effective therapeutic methods of morphine addiction.

Comparative Study of Aqueous and Ethanolic Leaf Extracts Of Spondias Mombin on Neurobehaviour in Male Rats

Remedies for anxiety and fear have been investigated through both orthodox and traditional medicine; this study compared the effects of chronic administration of graded doses of aqueous and ethanolic extracts of Spondias mombin on anxiety and fear in Albino Wistar rats. Fifty rats of Wistar strain (100-120g body weight) were divided into five major groups A-E with each group made up of ten rats (n=10). Spondias mombin (250, 400,500 and 800mg/kg) were orally administered for 4 weeks before testing. The elevated plus maze was used to assess anxiety behaviour. Following administration of graded doses of aqueous and ethanolic extracts of Spondias mombin for a period of four weeks, decreased anxiety and fear in the albino rats was revealed (p<0.05). The order of the anxiolytic property following these graded dose of administration was; duration and frequency in open arm of the 500mg/kg group was significantly higher (90.2 ± 37.2s & 4.4 ± 1.29/5min respectively) compared to control, and other treatment groups of Spondias mombin (P< 0.05). Duration in closed arm (260.33 ± 15.97s) was significantly lower compared to control. Closed arms frequency with 250mg/kg and 500mg/kg ethanol extract were 3 .83 ± 1.74/5min and 3.16 ± 1.40/5min. The extracts were significantly (P<0.05) lower compared with control (8.67 ± 1.05/5min). However, the 500mg/kg ethanol extract showed a lower frequency. The duration of grooming following four weeks of treatment with 250mg/kg and 500mg/kg ethanol extract of Spondias mombin were 8.68 ± 2.10s and 12. 1 ± 0.001s respectively and these were significantly lower compared to control. Spondias mombin dose-dependently decreased anxiety and fear with significant decrease observed in rats administered with ethanolic extracts of Spondias mombin. Anxiolytic effect is shown by decrease in the frequency of grooming and duration of grooming, decrease in frequency of head dipping and stretch attempt posture (SAP), and a lower frequency of close arm entry by the experimental groups. Ethanolic extract from Spondias mombin produced better behavioral effects with decreased anxiety and fear compared to the aqueous extract and so has a potential as an alternative anxiolytic and sedative agent compared to its aqueous extract.

Anxiolytic activity of aqueous extract of Garcinia indica in mice

Background: Anxiety or depressed mood is associated with low levels of serotonin in the brain. A hydroxycitric acid (HCA), constituent of Garcinia indica (GIA), increases serotonin release from isolated rat brain cortex. Aim: To evaluate the anxiolytic activity of aqueous extract of dried fruits of GIA in mice. Materials and Methods: The anxiolytic‑like effects of aqueous extract of dried fruits of GIA were evaluated by using elevated plus maze (EPM), hole board and light/dark exploration models in Swiss albino mice. Control mice were treated with an equal volume of saline, and positive control mice were treated with diazepam (1 mg/kg). Results: GIA administered orally, 30 min before the test in different doses (125, 250 and 500 mg/kg of body weight), was able to increase significantly (P < 0.05) the time‑spent and entries into open arms of the EPM and reduced the time‑spent and entries into closed arms versus control. In the hole‑board test, treatment with GIA (250 and 500 mg/kg) significantly increased the number of head‑dips and duration of head dipping (P < 0.05). In the light–dark paradigm test, number of transitions and the time spent in the light box increased with reduction in time spent in the dark box and immobility period significantly (P < 0.05) after treatment with GIA. However, no significant changes in locomotor activity were observed versus control. Conclusion: The results of the present study suggest that aqueous extract of dried fruits of GIA is an effective anxiolytic agent for behavioural models in mice. Key words: Anxiolytic, elevated plus maze, Garcinia indica, light/dark test, locomotor activity