OBJECTIVETo evaluate the effects of theanine on sedative effects induced by pentobarbital sodium.

METHODThe locomotor activities of ICR mice induced by theanine (0.25, 0.5, 1.0, 2.0, 4.0 g x kg(-1)), pentobarbital sodium (5, 10 mg x kg(-1)) or the combination of both were determined with video-tracking system, and a novel index: Peripheral active time Peripheral time (PATP) was established. Hypnosis effect of combination of both was tested with right-reflex disappearance.

RESULTCompared with normal saline (74.52 +/- 20.4)%, theanine alone decreased this PATP in dose-dependent manner from (62.03 +/- 21.11)%, (56.44 +/- 21.69)%, (31.13 +/- 17.2)%, (25.06 +/- 10.03)% to (17.21 +/- 7.43)% (P>0.05, P<0.05, P<0.01, P<0.01 and P<0.01, respectively). Compared with pentobarbital sodium (5 mg x kg(-1)), between 0.25 g x kg(-1) and 1.0 g x kg(-1) theanine combined with that decreased peripheral PATP from (28.30 +/- 17.57)%, (30.64 +/- 17.21)% to (24.28 +/- 9.59)% (all P<0.01), and increased by 2.0 g x kg(-1) reversely (61.95 +/- 19.39)%. Compared with normal saline, pentobarbital sodium (10 mg x kg(-1)) and the combination with theanine decreased significantly PATP (all P<0.01). Compared with pentobarbital sodium (10 mg x kg(-1)), 0.25 g x kg(-1) theanine combined with that increased PATP [(25.37 +/- 13.68)% vs (10.08 +/- 7.98)%, P<0.01)] and 0.5 g x kg(-1), 1.0 g x kg(-1) theanine could depresse that increase [(14.56 +/-10.10)%, (8.24 +/- 4.08)% vs (10.08 +/- 7.98)%]. Total distance and peripheral active time showed the same or similar tendency in theanine alone or combination with pentobarbital sodium . Theanine enchanced hypnosis effect of pentobarbital sodium in dose-dependent manner.

CONCLUSIONTheanine can affect the sedative effect of low dose pentobarbital sodium in bidirectional action style but not change the hypnosis effect.

Animals ; Drug Interactions ; Female ; Glutamates ; pharmacology ; Hypnotics and Sedatives ; pharmacology ; Male ; Mice ; Mice, Inbred ICR ; Motor Activity ; drug effects ; Pentobarbital ; pharmacology

This study is to investigate the sedative and hypnotic effects of a novel compound H1208. The sedative activity of H1208 was investigated by recording the spontaneous locomotor activity of mice. The hypnotic property was evaluated by the latency and duration of sleep (loss of righting reflex) in mice and the effect of hypnotics on sleep pattern of electroencephalogram were studied in conscious, freely moving mice with chronically implanted electrodes. The brain monoamine neurotransmitters levels in mice were measured by high performance liquid chromatography-electrochemical detection. The spontaneous locomotor activity was decreased by 56.7% and 80.2% in H1208 (5 and 25 mg x kg(-1), ip) treated mice, respectively. The loss of righting reflex was directly induced in mice after H1208 (60 mg x kg(-1), ip) administration. The non-rapid eye movement sleep increased significantly by 131% and 259%, respectively, within 3 hours after H1208 (30 and 60 mg x kg(-1), ip) administration. However, the rapid eye movement sleep decreased significantly. The contents of DA in the striatum and cortex and 5-HT in the cortex decreased significantly. These results demonstrated that H1208 has potent sedative and hypnotic effects, which may be closely related to the decreased contents of DA and 5-HT in mouse brain.
Animals ; Brain ; drug effects ; physiology ; Dopamine ; metabolism ; Electroencephalography ; Hypnotics and Sedatives ; pharmacology ; Mice ; Motor Activity ; drug effects ; Serotonin ; metabolism ; Sleep ; drug effects

OBJECTIVEThe present study aimed at investigating the effects of curcumin on the motor coordination and the estimate of the total number of cerebellar Purkinje cells of adolescent Wistar rats exposed to ethanol.

METHODSThe total of 21 male Wistar rats aged 37 d old were divided into three groups, namely ethanol, ethanol-curcumin, and control groups. The ethanol group received 1.5 g/kg ethanol injected intraperitoneally and water given per oral; the ethanol-curcumin group received 1.5 g/kg ethanol injected intraperitoneally and curcumin extract given per oral; the control group received saline injection and oral water. The treatment was carried out daily for one month, after which the motor coordination performance of the rats was examined using revolving drum apparatus at test days 1, 8, and 15. The rats were finally sacrificed and the cerebellum of the rats was further processed for stereological analysis. The estimate of the total number of Purkinje cells was calculated using physical fractionator method.

RESULTSThe ethanol-curcumin group performed better than both ethanol and control groups in the motor coordination ability at day 8 of testing (P< 0.01). No Purkinje cell loss was observed as a result of one month intraperitoneal injection of ethanol.

CONCLUSIONCurcumin may exert beneficial effects on the motor coordination of adolescent rats exposed to ethanol via undetermined hormetic mechanisms.

Animals ; Cell Count ; Cerebellum ; cytology ; drug effects ; Curcumin ; pharmacology ; Ethanol ; toxicity ; Male ; Motor Activity ; drug effects ; Psychomotor Performance ; Purkinje Cells ; cytology ; drug effects ; Rats ; Rats, Wistar

OBJECTIVETo study the effects of prenatal exposure to benzo[a]pyrene (B[a]P) on the physical development, early behavioral development, the adaptability to new environment and the learning and memory ability of rat offspring.

METHODSPregnant rats were randomly divided into five groups: control group, olive oil group, 3 exposure groups (25, 50 and 100 mg/kg B [a]P). The rats were exposed to B [a]P) by intraperitoneal injection on the 17th-19th days during gestation. The offspring were weighed on postnatal days (PND)1, PND 4, PND 7 and PND 28, the indices of physical development, reflective ability and sensory function were detected for offspring, the Morris water maze and Open-field tests were used to measure the ability of learning and memory and the adaptability to new environment of offspring.

RESULTSThe time of ear opening in middle and high-dose groups [(4.1 +/- 0.4),(5.0 +/-0.4) d] was posterior to that in untreated and solvent groups [(3.3 +/- 0.5), (3.4 +/- 0.6) d ](P < 0.01). The attainment rate (6.5%) of the surface righting reflex test in high-dose group on the 4th day was significantly lower than that (36.1%) in untreated group, the attainment rate (50.0%) in high-dose group on PND7 was significantly lower than those (81.3% and 79.3%) in untreated group and solvent group (P < 0.05). Compared to the untreated group, the time of forelimb hanging test in all exposure groups on PND12 and PND14 significantly decreased; compared to the solvent group the time of forelimb hanging test decreased in high-dose group on the 14th day significantly decreased (P < 0.01). The attainment rate (61.9%) of olfactory discrimination in high-dose group on PND12 was significantly lower than that (94.3%) in untreated group (P < 0.05). The results of Morris water maze test showed that the escape latency of different dose groups significantly increased, and the time of spatial probe and the times of traversing flat in high-dose group decreased significantly, as compared to the untreated and solvent groups (P < 0.01). The results of open-field test indicated that the center retention time in middle and high-dose groups significantly prolonged, the times of crossing lattice obviously reduced, and the rearing times decreased in high-dose group, as compared to untreated (P < 0.05).Compared to the solvent group, the times of crossing lattice in all exposure groups reduced significantly (P < 0.01 or P < 0.05).

CONCLUSIONThe prenatal exposure to B[a]P could inhibit the physical development and early behavioral development, and influence the adaptability to new environment and learning and memory ability for offspring.

Animals ; Benzo(a)pyrene ; toxicity ; Female ; Learning ; drug effects ; Maze Learning ; Memory ; drug effects ; Motor Activity ; Neurotoxicity Syndromes ; physiopathology ; Pregnancy ; Prenatal Exposure Delayed Effects ; physiopathology ; Rats ; Rats, Sprague-Dawley

OBJECTIVETo study the effect of aluminum chloride on motor and species-typical behaviors in mice.

METHODSMale ICR mice were administered with drinking double distilled water only containing AlCl(3) (10, 50, 300 mg x kg(-1) x d(-1)), and control group with drinking double distilled water only for 100 days. Spontaneous activity test, grip strength, beam traversal, tightrope task, food hoarding, and nest construction were used to study the effect of chloride aluminum on motor and species-typical behaviors in mice.

RESULTSThe frequencies of spontaneous activity in low dose group, medium dose group and high dose group [(81.53 +/- 8.97), (71.67 +/- 8.37), (66.73 +/- 6.96) times respectively] were lower than that in control [(106.46 +/- 8.21) times] (P < 0.01), and were negatively correlated with doses (r(s) = -0.42, P < 0.01). Grip strength scores in medium dose group (19.19 +/- 1.48) and high dose group (13.36 +/- 1.46) respectively were lower than that in control (24.31 +/- 1.43) (P < 0.05, P < 0.01). Food hoarding was greater in high dose group [96.10 (90.20-99.00) g] than that in control group [84.00 (78.00-90.00) g (P < 0.05)]. The rest of parameters were of no statistical significance.

CONCLUSIONSubchronic exposure to AlCl(3) in mice may diminish motor activity and grip strength, but motor coordination was not impaired; alteration in food hoarding suggests damage to hippocampus cell.

Aluminum Compounds ; toxicity ; Animals ; Behavior, Animal ; drug effects ; Chlorides ; toxicity ; Dose-Response Relationship, Drug ; Male ; Mice ; Mice, Inbred ICR ; Motor Activity ; drug effects

Besides its role in desensitization and internalization of receptors, β-arrestin2 facilitates G protein-independent signaling through its ability to scaffold various signaling molecules. β-arrestin2 is widely distributed in the central nervous system, and mediates signal transduction of brain circuit. The aim of the present study was to investigate the role of β-arrestin2 in reward behaviors induced by cocaine. We assessed the conditioned place preference (CPP) induced by low (10 mg/kg), moderate (20 mg/kg) and high (30 mg/kg) doses of cocaine in Arrb2(-/-) mice and Arrb2(+/+) controls. In the Arrb2(-/-) mice, moderate and high, but not low, dose of cocaine induced pronounced increases of CPP scores, which were higher than those in the Arrb2(+/+) mice. Moreover, cocaine-induced locomotor activity was significantly lower in Arrb2(-/-) mice than that of Arrb2(+/+) littermate controls. Taken together, our results suggest a potential role of β-arrestin2 in the cocaine-induced rewarding behaviors.
Animals ; Arrestins ; physiology ; Behavior, Animal ; drug effects ; Cocaine ; pharmacology ; Mice ; Mice, Knockout ; Motor Activity ; drug effects ; Reward ; beta-Arrestin 2 ; beta-Arrestins

OBJECTIVEStriatum may be involved in depressive disorders according to the neuroimaging analysis and clinical data. However, no animal model at present supported the possible role of striatum in the pathogenesis of depression. In the present study, we have investigated the depressive-like behavior in mice recently intoxicated with 3-nitropropionic acid (3-NP), a widely known toxin that selectively damages the striatum in the brain.

METHODSMouse model was made with subacute systemic 3-NP treatment, and the depressive-like behavior was measured using the duration of immobility during forced swimming test (FST).

RESULTSWhen the mice at day 15 post-intoxication just totally recovered from motor deficits, the duration of immobility in FST was significantly longer than that in controls. The depressive-like behavior was not due to the fatigue or general sickness following 3-NP intoxication and could be reversed by the antidepressant, desipramine hydrochloride. In two successive FST in 24 h interval, the depressive-like behavior could be observed again in subsequent FST (at day 16 post-intoxication), and the mice presented a normal "learned helplessness".

CONCLUSIONA novel depression animal model could be established in mice during the initial period of recovery from 3-NP intoxication. The depression-like behavior might occur independently without involvement of cognitive defects, and the striatal lesions may underlie the depression-like behavior attributable to 3-NP intoxication.

Animals ; Convulsants ; toxicity ; Corpus Striatum ; drug effects ; Depression ; chemically induced ; Disease Models, Animal ; Mice ; Motor Activity ; drug effects ; Nitro Compounds ; toxicity ; Propionates ; toxicity

Animals ; Drugs, Chinese Herbal ; pharmacology ; Female ; Gardenia ; chemistry ; Memory ; drug effects ; Mice ; Mice, Inbred ICR ; Motor Activity ; drug effects ; Plant Oils ; pharmacology ; Seeds ; chemistry ; Ziziphus ; chemistry

OBJECTIVETo explore the effects of embryonic lead exposure on motor function and balance ability in offspring rats and the possible mechanisms.

METHODSAn animal model of embryonic lead exposure was prepared with the use of pregnant Sprague-Dawley rats freely drinking 0.1% (low-dose group, LG) or 0.2% (high-dose group, HG) lead acetate solution. A normal control group (NG) was also set. The male offspring rats of these pregnant rats were included in the study, consisting of 12 rats in the NG group, 10 rats in the LG group, and 9 rats in the HG group. The offspring rats' motor function and balance ability were evaluated using body turning test and coat hanger test. Eight rats were randomly selected from each group, and immunohistochemistry and Timm's staining were employed to measure the expression of c-Fos and mossy fiber sprouting (MFS) in the hippocampus.

RESULTSThe HG group had a significantly longer body turning time than the NG and LG groups (P<0.05), and the LG group had a significantly longer body turning time than the NG group (P<0.05). The HG group had a significantly lower score of balance ability than the NG and LG groups (P<0.05), and the LG group had a significantly lower score of balance ability than the NG group (P<0.05). The area percentage of c-Fos-positive neurons in the hippocampal CA1 region was significantly higher in the HG group than in the other two groups (P<0.05), and it was significantly higher in the LG group than in the NG group (P<0.05). The semi-quantitative scores of MFS in the hippocampal CA3 region and dentate gyrus were significantly higher in the HG group than in the other two groups (P<0.05), and they were significantly higher in the LG group than in the NG group (P<0.05).

CONCLUSIONSEmbryonic lead exposure could impair the offspring rats' motor function and balance ability. These changes may be related to increased c-Fos expression in the hippocampal CA3 region and abnormal MFS in the hippocampal CA3 region and dentate gyrus.

Animals ; Female ; Fetus ; drug effects ; Hippocampus ; chemistry ; drug effects ; Lead ; toxicity ; Male ; Mossy Fibers, Hippocampal ; drug effects ; Motor Activity ; drug effects ; Postural Balance ; drug effects ; Pregnancy ; Proto-Oncogene Proteins c-fos ; analysis ; Rats ; Rats, Sprague-Dawley

OBJECTIVETo explore the effects of low-dose chlorpyrifos (CPF) exposure on dopaminergic (DA) neurons in the midbrain substantia nigra and neural behavioral development in neonatal rats.

METHODSPostnatal 11 day old Sprague-Dawley rats were randomly assigned into CPF, menstruum dimethysulfoxide (DMSO) and normal saline (NS) groups. The rats in the CPF group were injected with low-dose CPF (5 mg/kg?d) on postnatal days 11-14. The two control groups were injected with DMSO or NS respectively. The rats were sacrificed on postnatal days 15, 20, 30, and 60. Body weight gain, outward appearance of brain tissue, the coefficient of brain and the water content of brain tissue were measured. Tyrosine hydroxylase (TH) expression in DA neurons in the midbrain substantial nigra was examined by immunohistochemical straining. Immune electron microscopy was used to examine the subcellular structure of DA neurons. Open field test, grip strength test, slope test and Morris water maze test were used to examine the neurobehavioral changes.

RESULTSThe outward appearance of brain tissue was normal in the three groups. There were no significant differences in the absolute value of body weight gain, the coefficient of brain and the water content of brain tissue among the three groups. CPF exposure decreased the level of TH immunoreactivity (P<0.05) in the substantia nigra of CPF group since postnatal day 30 compared with the DMSO and NS groups. The subcellular structures of some DA neurons in the CPF group were impaired. Decreased motor activity and learning and memory impairments were observed in the CPF group compared with those in the DMSO and NS groups (P<0.05) since postnatal day 30.

CONCLUSIONSCPF exposure during the neonatal period can cause long-term motor activity and learning and memory impairments in accompany with DA neurons damage in the midbrain substantia nigra.

Animals ; Animals, Newborn ; Behavior, Animal ; drug effects ; Chlorpyrifos ; toxicity ; Dopaminergic Neurons ; drug effects ; Female ; Insecticides ; toxicity ; Learning ; drug effects ; Male ; Motor Activity ; drug effects ; Rats ; Rats, Sprague-Dawley ; Substantia Nigra ; drug effects