Evaluation of the anxiolytic effect of Nepeta persica Boiss. in mice

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

ETHNOPHARMACOLOGICAL RELEVANCE

Anxiety 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 STUDY

The 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 METHODS

The 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.

RESULTS

The 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.

CONCLUSIONS

In conclusion, A. catechu ethanolic extract improved anxiety symptoms at dose-dependent levels in mice.

Cytotoxic Effects of Some Nepeta Species against Breast Cancer Cell Lines and Their Associated Phytochemical Properties

Nepeta is one of the largest genera of the Lamiaceae family. Nepeta species are commonly employed in traditional medicine for a variety of ailments, as well as food additives. In addition, they also come to the fore with their rich phytochemical content. In the present study, the quantitative phytochemical content of methanolic extracts and infusions prepared from the aerial parts of 14 Nepeta taxa collected from Turkey and their cytotoxic effects on two breast cancer cell lines, MCF-7 and MDA-MB-231, were investigated by using the MTT (3-(4,5-dimethylthiazol-2-yl))-2,5-diphenyltetrazolium-bromide) test. According to HPLC-PDA analysis, N. racemosa methanolic extract had the highest ursolic acid content with 165.9 mg/g extract. Total sterol, total iridoid, and total triterpenoid content were determined to be greatest in the methanolic extracts of N. meyeri, N. trichocalyx and N. phyllochlamys. The MTT experiment demonstrated that certain Nepeta species suppressed the growth of MCF-7 and MDA-MB-231 cells in a dose-dependent manner. Statistical analysis revealed a strong correlation between the cytotoxic effects of the extracts and their triterpene content. In conclusion, the data obtained from this study are important in terms of forming a basis for advanced anticancer activity studies on breast cancer with Nepeta sp.

The genus Nepeta: Traditional uses, phytochemicals and pharmacological properties

ETHNOPHARMACOLOGICAL RELEVANCE

Nepeta is a multiregional genus of the "Lamiaceae" (Labiatae or Mint) family. Species of Nepeta are a valuable part of traditional medicine and used extensively, particularly in the Himalayan region of India (Uttarakhand, Himachal Pradesh, Jammu and Kashmir, Leh-Ladakh), Pakistan (Khyber Pakhtunkhwaand Pakistani Kashmir), Nepal (Baglund district), also in China and hilly regions of Turkey and Iran. Nepeta species are extensively used as a remedy against a variety of ailments and conditions like chicken pox, tuberculosis, malaria, pneumonia, influenza, measles, stomach disorders, eye complaints, respiratory disorders, asthma, colds, coughs etc. AIM OF THE REVIEW: The main aim of this review is to present a comprehensive and detailed study on traditional uses, pharmacology, phytochemistry, toxicology of Nepeta species and suggest future direction on the design and conduct of various preparations, either alone or in blends with prevailing conventional remedies. The review also emphasizes encouraging researchers towards the wide range of pharmaceutical applications of the various species of Nepeta for their better use and exploration in the future.

MATERIAL AND METHODS

All the relevant data and information on different species of Nepeta were assembled using different databases, such as Science Direct, Springer, PubMed, Taylor and Francis imprints, Chemspider, Google scholar, review and research articles from peer-reviewed journals and unpublished data. Some select 'grey literature' sources viz. ethnobotanical books, chapters, Wikipedia and webpages were also studied.

RESULTS

A variety of bioactive secondary metabolites and nutraceuticals has been isolated from various species of Nepeta. These bioactive compounds belong to different classes of secondary metabolites, such as phenolic acids and their glycosides (rosmarinic acid, gallic acid, caffeic acid), flavonoids and their glycosides (cirsimaritin, salvigenin, luteolin, apigenin), iridoids (nepetalactones and their derivatives), terpenoids (1,8-cineole, linalool, β-caryophyllene, germacrene D, parnapimaro, β-amyrin, oleanolic acid, ursolic acid), steroids (β-sitosterol, stigmasterol), lignans, amino acids, carbohydrates, volatile oils, etc. The species of the genus Nepeta possess a variety of pharmacological activities namely anti-inflammatory, anti-nociceptive, anti-alzheimer, anticancer and cytotoxic, antioxidant, immunomodulatory, antimicrobial, antifungal, insecticidal and along with other biological activities.

CONCLUSION

The species of the genus Nepeta contains a rich source of various bioactive compounds, which are well tolerated as traditional medicines. In fact, different species of Nepeta are widely used in a variety of traditional medicinal systems all around the world. Owing to the variety of pharmacological properties of Nepeta species, more comprehensive and inclusive clinical trials are necessary for the utilization of different Nepeta species against the treatment of a wide range of ailments. There are also various other uses such as food, cosmetic and agriculture that can be investigated or explored in future. Some of the major domains that can be explored within this genus are the investigation of different species for their unexplored biological potential, isolation and characterization of new bioactive constituents and finally, investigation of new applications and possible commercialization of these bioactive leads. No doubt, there are various viable research domains outside those discussed above, but presently for the purposes of this review we will only emphasize the activities herein.

Members of the family <i>Lamiaceae</i> Lindl. as sources of medicinal plant raw materials to obtain neurotropic drugs

The aim of this work is to review and analyze the data published in the modern scientific literature obtained in pharmacological, pharmacognostic and pharmacotechnological studies of various types of raw materials obtained from members of the family Lamiaceae L., which were sources of biologically active substances, pharmaceutical substances, total extracts and the drugs – with a neurotropic activity.

Materials and methods. For the review, we used the information of scientific literature from open and accessible sources of the last twenty years, located in the scientific and technical libraries of institutions, as well as in electronic databases: Elibrary, PubMed, Scopus, Cyberleninka, GoogleAcademy, J-Stage. The search inquiries were: the species of the family Lamiaceae (Russian and Latin), the samples of medicinal plant materials based on them as well as the names of the drugs and biologically active substances obtained from these raw materials.

Results. When working with the sources of scientific information, the main attention was paid to pharmacologic tests performed during the studies on laboratory animals and proving the presence of neurotropic activity in the studied objects – essential oils and extracts from plant raw materials: aqueous, aqueous alcoholic, and methanol ones. It has been established that the potential of the therapeutic and preventive application of pharmaceutical substances and drugs based on the medicinal plant materials obtained from 30 genera members of the Lamiaceae family, remains unrealized despite the close attention of various researchers.

Conclusion. This review comprised 71 species from 30 genera. Despite the significant level of the previous study presented in the analysis of this publication, an enormous potential of this family’s species remains unexplored. In the future, they can be of both – pharmacognostic and practical interest, in particular, in creation of new medicinal preparations of the neurotropic action based on them.

The anxiolytic-like effect of 6-styryl-2-pyrone in mice involves GABAergic mechanism of action

The present work aims to investigate the anxiolytic activity of 6-styryl-2-pyrone (STY), obtained from Aniba panurensis, in behavioral tests and amino acids dosage on male Swiss mice. The animals were treated with STY (1, 10 or 20 mg), diazepam (DZP 1 or 2 mg/kg) or imipramine (IMI 30 mg/kg). Some groups were administered with flumazenil, 30 min before administration of the STYor DZP. The behavioral tests performed were open field, rota rod, elevated plus maze (EPM), hole-board (HB) and tail suspension test (TST). After behavioral tests, these animals were sacrificed and had their prefrontal cortex (PFC), hippocampus (HC) and striatum (ST) dissected for assaying amino acids (aspartate- ASP, glutamate- GLU, glycine- GLY, taurine- TAU and Gamma-aminobutyric acid- GABA). In EPM test, STY or DZP increased the number of entries and the time of permanence in the open arms, but these effects were reverted by flumazenil. In the HB test, STY increased the number of head dips however this effect was blocked by flumazenil. The effects of the STY on amino acid concentration in PFC showed increased GLU, GABA and TAU concentrations. In hippocampus, STY increased the concentrations of all amino acids studied. In striatum, STY administration at lowest dose reduced GLU concentrations, while the highest dosage caused the opposite effect. GLI, TAU and GABA concentrations increased with STY administration at highest doses. In conclusion, this study showed that STY presents an anxiolytic-like effect in behavioral tests that probably is related to GABAergic mechanism of action.

Safety assessment and behavioral effects of Solanum guaraniticum leaf extract in rats

ABSTRACT Solanum guaraniticum is a medicinal plant traditionally used to treat gastric and liver diseases. However, there is no documented evidence corroborating its safety. The present study evaluated the potential toxicity of S. guaraniticum leaf extract after acute administration in rats. Single doses of the extract (1.250, 2.500, and 5.000 mg/kg) were administered by gavage, and the rats were then monitored for 48 h and/or 14 days. Mortality, acute signs of toxicity, and general activity in the open field test were assessed as well as hematological and biochemical parameters, enzymatic activity (δ-aminolevulinate dehydratase and acetylcholinesterase), and oxidative stress parameters (lipid peroxidation level, non-protein thiol content, tissue catalase activity, and serum ferrous reducing power). Phytochemical analysis was also performed by HPLC. The results showed that extract administration produced no deaths (LD50 > 5,000 mg/kg), and no significant adverse effects regarding food consumption, body weight gain, gross pathology, or other parameters. However, the open field tests showed a decrease in spontaneous activity (crossing and rearing) mainly at 48 h after treatment. The results suggest that S. guaraniticum extract is not acutely toxic, but causes alterations in central nervous system activity.

Anticancer Activity of Chloroform Extract and Sub-fractions of Nepeta deflersiana on Human Breast and Lung Cancer Cells: An In vitro Cytotoxicity Assessment

BACKGROUND

Cancer is one of the major causes of death worldwide. The plant-derived natural products have received considerable attention in recent years due to their diverse pharmacological properties including anticancer effects. Nepeta deflersiana (ND) is used in the folk medicine as antiseptic, carminative, antimicrobial, antioxidant, and for treating rheumatic disorders. However, the anticancer activity of ND chloroform extract has not been explored so far.

OBJECTIVES

The present study was aimed to investigate the anticancer activities of chloroform Nepeta deflersiana extract and various sub-fractions (ND-1-ND-15) of ND against human breast cancer cells (MCF-7) and human lung cancer cells (A-549).

MATERIALS AND METHODS

The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide and neutral red uptake assays, and cellular morphological alterations using phase contrast light microscope were studied. Cells were exposed with 10-1000 μg/ml of sub-fractions of ND for 24 h.

RESULTS

Results showed that selected sub-fractions of the chloroform extract significantly reduced the cell viability of MCF-7 and A-549 cells, and altered the cellular morphology in a concentration-dependent manner. Among the sub-fractions, ND-10 fraction showed relatively higher cytotoxicity compared to other fractions whereas, ND-1 did not cause any cytotoxicity even at higher concentrations. The A-549 cells were found to be more sensitive to growth inhibition by all the extracts as compared to the MCF-7 cells.

CONCLUSION

The present study provides preliminary screening of anticancer activities of chloroform extract and sub-fractions of ND, which can be further used for the development of a potential therapeutic anticancer agent.

SUMMARY

Nepeta deflersiana extract exhibit cytotoxicity and altered the cellular morphology. Sub-fractions of the chloroform extract of Nepeta deflersiana reduced the cell viability of MCF-7 and A-549 cells. Among the sub-fractions, ND-10 fraction showed relatively higher cytotoxicity. The A-549 cells were found to be more sensitive as compared to the MCF-7 cells. Abbreviations used: MTT: 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide; NRU: Neutral red uptake; DMEM: Dulbecco's modified eagle medium; FBS: Fetal bovine serum; PBS: Phosphate buffer saline; DMSO: Dimethyl sulfoxide.

Psychoneuropharmacological activities and chemical composition of essential oil of fresh fruits of Piper guineense (Piperaceae) in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Piper guineense Schum & Thonn (Piperaceae) is a medicinal plant used in the Southern States of Nigeria to treat fever, mental disorders and febrile convulsions.

AIMS OF THE STUDY

This study aims at determining the chemical composition and the central nervous system (CNS) activities of the essential oil obtained from the plant׳s fresh fruits in order to rationalize its folkloric use.

MATERIALS AND METHODS

Essential oil of P. guineense (EOPG) obtained by hydrodistillation was analysed by GC/MS. EOPG (50-200mg/kg, i.p.) was evaluated for behavioural, hypothermic, sedative, muscle relaxant, anti-psychotic and anticonvulsant activities using standard procedures.

RESULTS AND DISCUSSION

Analysis of the oil reveals 44 compounds of which 30 compounds constituting 84.7% were identified. The oil was characterized by sesquiterpenoids (64.4%) while only four monoterpeneoids (21.3%) were found present in the oil. Major compounds identified were β-sesquiphellandrene (20.9%), linalool (6.1%), limonene (5.8%), Z-β-bisabolene (5.4%) and α-pinene (5.3%). The EOPG (50-200mg/kg, i.p.) caused significant (p<0.01) inhibition on rearing {F(4,20)=43}, locomotor {F(4,20)=22} activity and decreased head dips in hole board {F(4,20)=7} indicating CNS depressant effect; decreased rectal temperature {F(4,20)=7-16}, signifying hypothermic activity; decreased ketamine-induced sleep latency {F(4,20)=7.8} and prolonged total sleeping time {F(4,20)=8.8}, indicating sedative effect; reduced muscular tone on the hind-limb grip test {F(4,20)=22}, inclined board {F(4,20)=4-49} and rota rod {F(4,20)=13-106}, implying muscle relaxant activity; induced catalepsy {F(4,20)=47-136}, inhibited apomorphine-induced climbing behaviour {F(4,20)=9} and inhibited apomorphine-induced locomotor {F(4,20)=16}, suggesting anti-psychotic effect; and protected mice against pentylenetetrazole-induced convulsions, indicating anticonvulsant potential.

CONCLUSION

The most abundant component of the fresh fruits essential oil of P. guineense was β-sesquiphellandrene (20.9%); and the oil possesses CNS depressant, hypothermic, sedative, muscle relaxant, antipsychotic and anticonvulsant activities, thus providing scientific basis for its ethnomedicinal applications.

Evaluation of anxiolytic and sedative effect of essential oil and hydroalcoholic extract of Ocimum basilicum L. and chemical composition of its essential oil

Ocimum basilicum belongs to Lamiaceae family and has been used for the treatment of wide range of diseases in traditional medicine in Iranian folk medicine. Due to the progressive need to anti-anxiety medications and because of the similarity between O. basilicum and Salvia officinalis, which has anti-anxiety effects, we decided to investigate the anxiolytic and sedative activity of hydroalcoholic extract and essential oil of O. basilicum in mice by utilizing an elevated plus maze and locomotor activity meter. The chemical composition of the plant essential oil was also determined. The essential oil and hydroalcoholic extract of this plant were administered intraperitoneally to male Syrian mice at various doses (100, 150 and 200 mg/kg of hydroalcoholic extract and 200 mg/kg of essential oil) 30 min before starting the experiment. The amount of hydroalcoholic extract was 18.6% w/w and the essential oil was 0.34% v/w. The major components of the essential oil were methyl chavicol (42.8%), geranial (13.0%), neral (12.2%) and β-caryophyllene (7.2%). HE at 150 and 200 mg/kg and EO at 200 mg/kg significantly increased the time passed in open arms in comparison to control group. This finding was not significant for the dose of 100 mg/kg of the extract. None of the dosages had significant effect on the number of entrance to the open arms. Moreover, both the hydroalcoholic extract and the essential oil decreased the locomotion of mice in comparison to the control group. This study shows the anxiolytic and sedative effect of hydroalcoholic extract and essential oil of O. basilicum. The anti-anxiety and sedative effect of essential oil was higher than the hydroalcoholic extract with the same doses. These effects could be due to the phenol components of O. basilicum.

Investigation of in vivo neuropharmacological effect of Alpinia nigra leaf extract

OBJECTIVE

To analyze in vivo neuro-pharmacological effects of Alpinia nigra as anxiety is a particular form of behavioral inhibition that occurs in response to novel environmental events.

METHODS

In present study, the extract of Alpinia nigra was evaluated for its central nervous system depressant effect using mice behavioral models, such as hole cross, open field and thiopental sodium induced sleeping time tests for its sedative properties and an elevated plus-maze test for its anxiolytic potential, respectively.

RESULTS

In anxiolytic study, the extract displayed increased percentage of entry into open arm at the dose of 400 and 200 mg/kg. The extract produced a significant (P<0.01) increase in sleeping duration and reduction of onset of sleep compared to sodium thiopental at both doses (200 and 400 mg/kg). The extract (200 and 400 mg/kg) also showed a dose-dependent suppression of motor activity and exploratory activity of the mice in both open field and hole cross test.

CONCLUSION

This study demonstrates that the treated extract has significant central nervous system depressant effect. Further studies on active constituent of the extract can provide approaches for therapeutic intervention.

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.

Evaluation of the sedative and anticonvulsant properties of three Cameroonian plants

Millettia thonningii, Ocinum sanctum and Securitaca longepedunculaca are used in traditional medicine in Cameroon to treat epilepsy, insomnia and headaches. Animal models of epilepsy (maximal electroshock (MES), n-methyl-d-aspartate (NMDA), pentylenetetrazol (PTZ), isonicotinic hydrazide acid (INH), picrotoxine (PIC) and strychnine (STR)-induced convulsions or turning behavior were used to evaluate anticonvulsant activity while diazepam-induced sleep test was used to evaluate sedative activity of the plants. Four doses of extracts were used for each plant (100, 200, 500 and 1000 mg/kg). At a dose of 1000 mg/kg, Millettia thonningii protected 60 and 90% of mice against MES and PTZ-induced convulsions, respectively. At the same dose, Millettia thonningii also protected 80% of mice against NMDA-induced turning behavior. At a dose of 1000 mg/kg, Ocinum sanctum provided complete protection against MES, PIC and STR- induced convulsions and 83.3% of protection in PTZ test. Securitaca longepedunculata completely protected (100%) mice in PIC test at a dose of 200 mg/kg, in MES test at a dose of 500 mg/kg and in PTZ test at a dose of 1000 mg/kg. 66.7% of mice were protected against STR-induced convulsions. All the three plants showed also sedative properties for they increased significantly and in a dose dependent manner the total sleep time induced by diazepam. The total sleep time of the control groups was multiplied by a factor of 3 at least by each extract. The presence of sedative and anticonvulsant activity in the three plants could explain their use in traditional medicine in the treatment of epilepsy and insomnia in Cameroon.

Acupuncture Attenuates Anxiety-Like Behavior by Normalizing Amygdaloid Catecholamines during Ethanol Withdrawal in Rats

Previously, we demonstrated acupuncture at acupoint HT7 (Shen-Men) attenuated ethanol withdrawal syndrome by normalizing the dopamine release in nucleus accumbens shell. In the present study, we investigated the effect of acupuncture on anxiety-like behavior in rats and its relevant mechanism by studying neuro-endocrine parameters during ethanol withdrawal. Rats were treated with 3 g kg(-1)day(-1) of ethanol (20%, w/v) or saline by intraperitoneal injections for 28 days. The rats undergoing ethanol withdrawal exhibited anxiety-like behavior 72 h after the last dose of ethanol characterized by the decrease of time spent in the open arms of the elevated plus maze compared with the saline-treated rats (P < .05). Radioimmunoassay exhibited there were notably increased concentrations of plasma corticosterone in ethanol-withdrawn rats compared with saline-treated rats (P < .05). Additionally, high performance liquid chromatography analysis also showed the levels of norepinephrine and 3-methoxy-4-hydroxy-phenylglycol were markedly increased while the levels of dopamine and 3,4-dihydroxyphenylacetic acid were significantly decreased in the central nucleus of the amygdala of ethanol-withdrawn rats compared with saline-treated rats (P < .01). Acupuncture groups were treated with acupuncture at acupoint HT7 or PC6 (Nei-Guan). Acupuncture at HT7 but not PC6 greatly attenuated the anxiety-like behavior during ethanol withdrawal as evidenced by significant increases in the percentage of time spent in open arms (P < .05). In the meantime, acupuncture at HT7 also markedly inhibited the alterations of neuro-endocrine parameters induced by ethanol withdrawal (P < .05). These results suggest that acupuncture may attenuate anxiety-like behavior during ethanol withdrawal through regulation of neuro-endocrine system.

Psychological stress induces temporary masticatory muscle mechanical sensitivity in rats

To explore the relationship between psychological stress and masticatory muscle pain, we created a communication stress animal model to determine whether psychological stress could induce increased mechanical sensitivity in masticatory muscles and to study the changes of mechanical nociceptive thresholds after stress removal. Forty-eight male Sprague-Dawley rats were divided into a control group (CON), a foot-shocked group (FS, including 3 subgroups recorded as FS-1, FS-2, and FS-3), a psychological stress group (PS), and a drug treatment group (DT). PS and DT rats were confined in a communication box for one hour a day to observe the psychological responses of neighboring FS rats.Measurements of the mechanical nociceptive thresholds of the bilateral temporal and masseter muscles showed a stimulus-response relationship between psychological stress and muscle mechanical sensitivity. The DT rats, who received a diazepam injection, showed almost the same mechanical sensitivity of the masticatory muscles to that of the control in response to psychological stress. Fourteen days after the psychological stressor was removed, the mechanical nociceptive thresholds returned to normal. These findings suggest that psychological stress is directly related to masticatory muscle pain. Removal of the stressor could be a useful method for relieving mechanical sensitivity increase induced by psychological stress.

A Valepotriate Fraction of Valeriana glechomifolia Shows Sedative and Anxiolytic Properties and Impairs Recognition But Not Aversive Memory in Mice

Plants of the genus Valeriana (Valerianaceae) are used in traditional medicine as a mild sedative, antispasmodic and tranquilizer in many countries. This study was undertaken to explore the neurobehavioral effects of systemic administration of a valepotriate extract fraction of known quantitative composition of Valeriana glechomifolia (endemic of southern Brazil) in mice. Adult animals were treated with a single intraperitoneal injection of valepotriate fraction (VF) in the concentrations of 1, 3 or 10 mg kg⁻¹, or with vehicle in the pre-training period before each behavioral test. During the exploration of an open field, mice treated with 10 mg kg⁻¹ of VF showed reduced locomotion and exploratory behavior. Although overall habituation sessions for locomotion and exploratory behavior among vehicle control and doses of VF were not affected, comparison between open-field and habituation sessions within each treatment showed that VF administration at 1 and 10 mg kg⁻¹ impaired habituation. In the elevated plus-maze test, mice treated with VF (10 mg kg⁻¹) showed a significant increase in the percentage of time spent in the open arms without significant effects in the number of total arm entries. VF at 3 mg kg⁻¹ produced an impairment of novel-object recognition memory. In contrast, VF did not affect fear-related memory assessed in an inhibitory avoidance task. The results indicate that VF can have sedative effects and affect behavioral parameters related to recognition memory.

Sedative and antiepileptic effects of Anthocephalus cadamba Roxb. in mice and rats

OBJECTIVE

The aim of the present study was to evaluate the sedative and antiepileptic activities of ethanolic extract of Anthocephalus cadamba (ACE) bark in various experimental animal models.

MATERIALS AND METHODS

ACE was tested at three doses viz. 100, 200 and 400 mg/kg p.o. We used ketamine-induced sleeping time model to test the sedative property of the extract where, onset and duration of sleep were observed. A paradigm of anticonvulsant models (pentylenetetrazole, isoniazid and maximal electroshock-induced seizures) were used to evaluate its protective effect against absence and generalized types of seizures. Onset of clonic convulsions, tonic extension and time of death were observed in PTZ and INH-induced seizure models. In MES model, duration of tonic hind leg extension and onset of stupor were observed.

RESULTS

ACE showed significant increase in ketamine induced sleeping time. It also exhibited significant increase (P<0.05, 0.01 and 0.001) in latency to clonic convulsion, tonic extension and time of death in PTZ and INH models at all tested doses, whereas in the MES model, the lower dose was found to be effective when compared with the higher doses (200 and 400 mg/kg, p.o.).

CONCLUSION

The results of the present investigation demonstrated that ACE possesses sedative and antiepileptic activities.

Psychological stress alters ultrastructure and energy metabolism of masticatory muscle in rats

To investigate the effects of psychological stress on the masticatory muscles of rats, a communication box was applied to induce the psychological stress (PS) in rats. The successful establishment of psychological stimulation was confirmed by elevated serum levels of adrenocorticotropic hormone (ACTH) and changed behaviors in the elevated plusmaze apparatus. The energy metabolism of the bilateral masseter muscles was tested via chemocolorimetric analysis, whereas muscle ultrastructure was assessed by electron microscopy. In comparison to the control group, the PS group showed evidence of swollen mitochondria with cristae loss and reduced matrix density in the masticatory muscles after three weeks of stimulation; after five weeks of stimulation, severe vacuolar changes to the mitochondria were observed. Increased vascular permeability of the masticatory muscle capillaries was found in the five-week PS rats. In addition, there was decreased activity of Na⁺-K⁺ATPase and Ca²⁺-ATPase and a simultaneous increase in the activity of lactate dehydrogenase and lactic acid in the masticatory muscles of PS rats. Together, these results indicate that psychological stress induces alterations in the ultrastructure and energy metabolism of masticatory muscles in rats.