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Elevated Plus-maze Test (elevated + plus-maze_test)
Selected AbstractsEarly weaning decreases play-fighting behavior during the postweaning developmental period of wistar ratsDEVELOPMENTAL PSYCHOBIOLOGY, Issue 4 2007Michito Shimozuru Abstract We examined the influence of early weaning on the development of play-fighting behaviors and anxiety status in Wistar rats. Pups were divided into two groups, those weaned at postnatal day (PD) 16 (early-weaned group) and those weaned at PD30 (normally weaned group), and were housed in pairs of the same sex. Playful interactions were measured for each pair once a week from 4 to 7 weeks of age. Thereafter, during early adulthood, all the rats were subjected to the elevated plus-maze test. The frequencies of pinning and playful attack were less in the early-weaned group than in the normally weaned group. In the elevated plus-maze test, rat pups in the early-weaned group had higher anxiety levels. The results showed that deprivation of mother,pup interactions during the preweaning period decreases affiliative interactions between cage mates, including play-fighting behaviors during the postweaning developmental period, and increases anxiety levels during early adulthood. © 2007 Wiley Periodicals, Inc. Dev Psychobiol 49: 343,350, 2007. [source] Effects of central and systemic injections of peripheral benzodiazepine receptor ligands on the anxiolytic actions of ethanol in ratsADDICTION BIOLOGY, Issue 2 2001G. S. Morato The influence of peripheral benzodiazepine receptor ligands Ro5-4864 (0.05 or 1.0 mg/kg, i.p.) or PK11195 (0.05 or 1.0 mg/kg, i.p.) on the anxiolytic effect of ethanol (1.2 g/kg; 14% p/v; i.p.) was investigated in rats tested on the elevated plus-maze. Other animals were injected through intrahippocampal administrations of the ligands (0.5 or 1.0 nmol/0.5 ,l) before ethanol (1.2g/kg; 14% p/v; i.p.) and submitted to the elevated plus-maze test. The results showed that the systemic administration of either ligands 24 hours before the ethanol treatment resulted in a reduced anxiolytic effect of this drug. Only PK11195 reversed the effect of ethanol after intrahippocampal injection. These data suggest that peripheral benzodiazepine receptors play a role in ethanol anxiolysis. [source] The effects of genetic and pharmacological blockade of the CB1 cannabinoid receptor on anxietyEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 7 2002J. Haller Abstract The aim of this study was to compare the effects of the genetic and pharmacological disruption of CB1 cannabinoid receptors on the elevated plus-maze test of anxiety. In the first experiment, the behaviour of CB1-knockout mice and wild-type mice was compared. In the second experiment, the cannabinoid antagonist SR141716A (0, 1, and 3 mg/kg) was administered to both CB1-knockout and wild type mice. Untreated CB1-knockout mice showed a reduced exploration of the open arms of the plus-maze apparatus, thus appearing more anxious than the wild-type animals, however no changes in locomotion were noticed. The vehicle-injected CB1-knockout mice from the second experiment also showed increased anxiety as compared with wild types. Surprisingly, the cannabinoid antagonist SR141716A reduced anxiety in both wild type and CB1 knockout mice. Locomotor behaviour was only marginally affected. Recent evidence suggests the existence of a novel cannabinoid receptor in the brain. It has also been shown that SR141716A binds to both the CB1 and the putative novel receptor. The data presented here supports these findings, as the cannabinoid receptor antagonist affected anxiety in both wild type and CB1-knockout mice. Tentatively, it may be suggested that the discrepancy between the effects of the genetic and pharmacological blockade of the CB1 receptor suggests that the novel receptor plays a role in anxiety. [source] Confirmation of the anxiolytic-like effect of dihydrohonokiol following behavioural and biochemical assessmentsJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 5 2001Yuji Maruyama Previous studies in this laboratory revealed that dihydrohonokiol-B (DHH-B; 3,-(2 propenyl)-5-propyl-(1,1,-biphenyl)-2,4,-diol), a partially reduced derivative of honokiol, was an effective anxiolytic-like agent in mice at an oral dose of 0.04 mg kg,1, and at higher doses, when evaluated by the elevated plus-maze test. The aim of this study was to further confirm the anxiolytic-like effect of DHH-B using an additional behavioural procedure (Vogel's conflict test in mice) and a biochemical assessment (in-vitro determination of muscimol-stimulated 36Cl, uptake into mouse cortical synaptoneurosomes). As in earlier experiments, DHH-B (0.04,1 mg kg,1, p.o.) was shown to prolong the time spent in the open-sided arms of the elevated plus-maze in a dose-dependent manner. Moreover, in the Vogel's conflict test, DHH-B (5 mg kg,1, p.o.) significantly increased punished water intake. In tests with mouse cerebral cortical synaptoneurosomes, 10 and 30 ,m of DHH-B significantly increased 36Cl, influx in the absence of muscimol. In the presence of 25 ,m muscimol, the addition of 1 ,m DHH-B led to significant enhancement of 36Cl, uptake, while 30 ,m DHH-B was required to further stimulate the 36Cl, uptake induced by 250 ,m muscimol. The results of these studies confirm that DHH-B is a potent anxiolytic-like agent and that GABAA receptor-gated Cl, -channel complex is involved in the anxiolytic-like efficacy of DHH-B. [source] The Anxiolytic Effect of Two Oriental Herbal Drugs in Japan Attributed to Honokiol from Magnolia BarkJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 11 2000HISASHI KURIBARA An improved elevated plus-maze test in mice revealed that seven daily treatments with two differnt traditional Chinese medicines, known as Kampo medicines in Japan, Hange-koboku-to (composed of extracts of 5 plants) and Saiboku-to (composed of extracts of 10 plants), produced an anxiolytic effect, and the effect was mainly due to the presence of honokiol derived from magnolia. This study was carried out to evaluate the anxiolytic potential of honokiol, Hange-koboku-to and Saiboku-to, which were prescribed with two different magnolia samples: Kara-koboku (Magnoliae officinalis) (KA) or Wa-koboku (Magnoliae obovata) (WA). The doses of test samples were adjusted to ensure a constant dose of honokiol at 0.2 mg kg,1. Although the doses of magnolol (an isomer of honokiol), as well as those of undetermined chemicals, varied among samples, the seven daily treatments with 9 out of 10 test samples produced an anxiolytic effect almost equivalent to that produced by 0.2 mg kg,1 honokiol. The only exception was the sample containing the lowest amount of honokiol. Magnolia-free preparations of Hange-koboku-to or Saiboku-to did not have any anxiolytic effect. These results confirm that honokiol derived from magnolia is the causal chemical of the anxiolytic effect of Hange-koboku-to and Saiboku-to. [source] Evaluation of anxiolytic activity of spray dried powders of two South Brazilian Passiflora speciesPHYTOTHERAPY RESEARCH, Issue 5 2006Flįvio H. Reginatto Abstract The Passiflora extracts have been used in folk medicine because of its reputed sedative and anxiolytic properties. The present study aimed to compare the potential anxiolytic activity of two Passiflora spray-dried powders obtained from P. alata and P. edulis, known in Brazil as ,maracujį'. Male adult Swiss rats were treated with 200, 400 and 800 mg/kg of spray-dried powders p.o. and anxiolytic activity was evaluated using the elevated plus-maze test. The spray-dried powders showed anxiolytic activity in doses of 400 and 800 mg/kg. Our results support the potential anxiolytic effect of Passiflora spray-dried powders (P. alata and P. edulis). Copyright © 2006 John Wiley & Sons, Ltd. [source] The anxiolytic effect of Sho-ju-sen, a Japanese herbal medicine, assessed by an elevated plus-maze test in micePHYTOTHERAPY RESEARCH, Issue 2 2001Hisashi Kuribara Abstract Sho-ju-sen (SK), a Japanese herbal medicine with a nourishing tonic action, is composed of a water extract of Kumazasa leaves (Sasa kurinensis Makino et Sibata) (SS), and ethanol extracts of Japanese red pine needles (Pinus densiflora Sieb. et Zucc) (PN) and Ginseng roots (Panax ginseng C. A. Meyer) (PX) in the ratio 8:1:1. In this study, an elevated plus-maze test in mice was carried out to assess whether SK had an anxiolytic effect. No significant change was observed in either the plus-maze or activity test following a single administration of SK (10 and 20,mL/kg p.o.). However, mice allowed a free intake of SK (10% solution) for 5 days and longer showed a significant prolongation of the time spent in the open arms (an anxiolytic effect), as long as that caused by the benzodiazepine anxiolytic diazepam (1,mg/kg p.o.). SK (1%, 3% and 30% solutions for 7 days) tended to develop the anxiolytic effect. Of the constituents of SK, SS (8% solution), but not PN (1% solution) or PX (1% solution), resulted in the anxiolytic effect. Except for a slight acceleration in the motor activity by PN (1% solution), no significant change in the motor activity was produced by any treatment with SK, SS or PX. The combined treatment of SK (10% solution) or SS (8% solution) with 1,mg/kg diazepam enhanced the anxiolytic effect. Flumazenil (0.1,mg/kg s.c.), a benzodiazepine receptor antagonist, alone did not change the time spent in the open arms. However, it completely reversed the anxiolytic effect of SK, SS and diazepam. The present results suggest that: (1) long-term treatment with SK develops an anxiolytic effect, (2) SS is the main constituent for the anxiolytic effect of SK, and (3) benzodiazepine receptors are involved in the anxiolytic effect of SK and SS. Copyright © 2001 John Wiley & Sons, Ltd. [source] |