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The hydroalcoholic extract of Centella asiataica L. leaves was subjected to pharmacological screening using various experimental models. The extract was found to show protective action against increase in current electroshock (ICES) and chemoconvulsions, which includes pentylenetetrazol-induced convulsions, pentylenetetrazol-kindled seizures, and strychnine-induced opisthotonus tonic convulsions. It also showed a reduction in formation of lipid peroxidation products, reduction in spontaneous motor activity, potentiation in diazepam withdrawal-induced hyperactivity, hypothermia, and potentiation of pentobarbitone sleeping time. An extract was administered orally to the animals in all the studies. The extract (200 mg/kg body weight) completely inhibited pentylenetetrazol-induced convulsions. In pentylenetetrazol-kindled seizures and strychnine-induced convulsions, the extract showed protection at a dose of 100 mg/kg body weight. The doses of the extract of selected for remaining studies were based on pilot studies, animal model used, and so forth. These findings suggest that C. asiatica extract possesses potential anticonvulsant, antioxidant, and central nervous system depressant actions. [ABSTRACT FROM AUTHOR]

A reduced ability to thermoregulate and to adapt to low temperatures is a prominent feature in aged animals. We investigated whether the ability to adapt to cold exposure was different between an accelerated senescence prone strain of mice, SAMP1, and an accelerated senescence resistant strain of mice, SAMR1, at a young age. Using a telemetry system, we recorded the core temperature of mice in a cold environment (5±1 °C) and under conventional conditions (23±2 °C). No significant differences were observed between these two strains for core temperature during both daytime and night at room temperature, and for the lowest core temperature during cold exposure. The SAMR1 mice took a significantly shorter time to reach their lowest core temperature than the SAMP1 mice. The SAMP1 mice showed a significant positive correlation between spontaneous motor activity (SMA) counts at room temperature and those under cold exposure. The norepinephrine levels of the SAMP1 mice were significantly higher than the SAMR1 mice at room temperature, but decreased to the same level as the SAMR1 mice after cold exposure for 3 h. These results suggest that the adaptation mechanism to low temperature of SAMP1 mice may be different from that of SAMR1 mice, even at a young age. [Copyright &y& Elsevier]

We examined the diurnal rhythms of food and water intake, spontaneous wheel running (SWR), and spontaneous motor activity (SMA) in the SAMP1 strain, a mouse model of accelerated senescence. Without SWR exercise, food, and water intake in the SAMP1 mice was significantly higher during the light (L)-phase of the light–darkness (LD) cycle than in the control SAMR1 strain. Additionally, SWR and SMA activity rhythms were split in SAMP1 mice, as demonstrated by the appearance of a secondary peak starting from the end of the dark (D)-phase. SWR exercise significantly increased the percentages of nocturnal food and water intake and SMA in the SAMP1 mice, although food and water intake did not reach the level of control SAMR1 mice. Thus, the disordered diurnal rhythms in SAMP1 mice can be normalized, even if only partially, by SWR exercise. [Copyright &y& Elsevier]

The aqueous extract of Crinum giganteum given intraperitoneally at doses of 6.25, 12.5 and 25 mg/kg in rats prolonged the duration of pentobarbital sleeping time and in mice reduced spontaneous motor activity, decreased the exploratory activity and attenuated amphetamine-induced stereotype behavior. The intraperitoneal and oral preliminary LD50 in mice were found to be 627 and 1468 mg/kg, respectively. The data obtained suggest that the aqueous extract of C. giganteum contains some biologically active principles with sedative activity. [Copyright &y& Elsevier]

Patients with pervasive developmental disorders, including autism, and attention-deficit hyperactivity disorder show behavioral hyperactivity during childhood. We investigated the effects of a neonatal 6-hydroxydopamine lesion on multiple gene expression in the rat striatum and midbrain. Spontaneous motor activity was significantly increased at 4–5 weeks of age. The animals were sacrificed, and the striatum and midbrain were subjected to gene expression profiling using a membrane array with 1176 kinds of cDNAs. Alterations were found in several classes of gene expression, depending on the brain region. Enhanced expression of the glutamate transporter gene was found in the striatum. Expression of the dopamine receptor D4 gene and dopamine transporter gene was also increased in the midbrain. These results suggest that 6-hydroxydopamine-treated rats may partly mimic human hyperkinesia not only in behavior but also in gene expression. [Copyright &y& Elsevier]

The aim of this study was to determine if the psychostimulants, khat and amphetamine, exert similar effects in two tests of motor behaviors. Dose–response relationships were obtained for khat extract and d- and l-amphetamine given to mice by the intragastric route. Head twitch responses were significantly increased by khat and amphetamines. The latter were more potent than khat; dose–response curves for amphetamines had inverted U shapes. Khat extract decreased spontaneous motor activity, as measured by a photoactometer. Effects of amphetamines in this test were more variable and subject to dose dependent reversal. Other behaviors produced by higher doses of amphetamines interfered with specific motor responses under evaluation. Pretreatment with methysergide, a serotonin antagonist, significantly blocked head twitch responses but not spontaneous activity. Conversely, pretreatment with haloperidol decanoate, a dopamine receptor antagonist, prevented inhibition of spontaneous motor activity ordinarily evoked by khat and low dose d-amphetamine. We conclude that motor effects of khat and amphetamine resemble one another, but only at certain doses. Unlike khat, amphetamine causes additional behaviors that obscure motor responses of the types examined here. Results with transmitter receptor blockers suggest that motor effects of khat, like those of amphetamine, may be modulated by serotonin and dopamine. [Copyright &y& Elsevier]

This study compared spontaneous motor activity in 6-month-old Chilean infants with or without iron-deficiency anemia (IDA) who were otherwise healthy. Activity was assessed in conjunction with polysomnographic recording during an afternoon nap in 11 infants with IDA and 15 with normal hemoglobin levels. All infants were given oral iron, and activity was reassessed at 12 and 18 months. Using actigraphs placed on the ankle, the frequency of movement units per minute was determined for each waking/sleep state. The total amount of time infants were in an alert–active state before and after the nap was used to calculate the proportion of movements/minute of waking. There were no differences between anemic and nonanemic infants in total recording time, duration of sleep, or motor activity during sleep. However, infants with IDA showed reduced motor activity during waking at all ages. The magnitude of the differences increased at 12 and 18 months. Thus, IDA was associated with reduced motor activity in infants even after iron treatment. It will be important to confirm these results in a larger sample and to determine the 24-h pattern of motor activity, since reduced motor activity may limit infants'' opportunities to explore and learn from the social and physical environment. [Copyright &y& Elsevier]

Neuropharmacological activities of the methanol extract of the whole plant of Shankhapushpi, Convolvulus microphyllus Sieb ex Spreng (Convolvulaceae), were studied in experimental animals. The extract was found to produce alterations in the general behaviour pattern, reduction in spontaneous motor activity, hypothermia, potentiation of pentobarbitone-sleeping time, reduction in exploratory behavioural pattern, and suppression of aggressive behaviour. The extract also showed an inhibitory effect on conditioned avoidance response and antagonism to amphetamine toxicity. These findings explicitly suggest that the whole plant extract of C. microphyllus possesses a potential CNS-depressant activity. [ABSTRACT FROM AUTHOR]

The effects of 3-quinuclidinyl benzilate (QNB) in the rat were evaluated on a fixed-ratio (FR) schedule of water reinforcement and on open field behavior in a novel environment. QNB had a biphasic effect on FR-20 responding: at a low dose (0.01 mg/kg SC) it increased, and at moderate to higher doses (0.05-1.0 mg/kg SC) it decreased bar pressing in a dose-dependent manner. The effect of QNB on the multiple indices of open field activity showed that at the low dose (0.01 mg/kg SC) it depressed spontaneous motor activity (SMA), while at higher doses (0.5 and 1.0 mg/kg SC) it enhanced SMA: rearing and forelimb flicks were unaffected at low doses and increased at higher doses. In general, QNB appears to produce differential effects on operant responding and open field activity. [ABSTRACT FROM AUTHOR]

Parenteral administration of the adenosine deaminase (ADA) inhibitor erythro-9-(2-hydroxy-3-nonyl)-adenine (EHNA) results in a profound decrease in spontaneous motor activity in mice and rats. The inhibition of cortical ADA activity measured ex vivo parallels the decrease in spontaneous motor activity in a time-dependent manner. Nonetheless, a marked reduction in electroencephalographically defined sleep was observed in rats during a period when both spontaneous motor activity and ADA activity were profoundly inhibited. These data suggest that EHNA produces in rats a state of 'quiescent waking', which may be related to the observed inhibition of brain ADA activity. [ABSTRACT FROM AUTHOR]

The spontaneous motor activity (SMA) of rats was recorded after injections of saline, d-amphetamine sulfate (0.8 mg/kg), and ethanol (400, 800, 1200, and 1600 mg/kg). Each drug treatment was given separately, and the amphetamine treatment was also combined with each ethanol dose. Ethanol, when injected without amphetamine, produced a dose-related decrement in SMA. Amphetamine, injected without ethanol, produced an increase in SMA. The combination of ethanol at 400 mg/kg with amphetamine potentiated the amphetamine-stimulant effect, but higher doses of ethanol counteracted amphetamine-produced increment in SMA. In a second experiment, similar combinations of ethanol and amphetamine were administered to rats leverpressing for food pellets under a fixed-interval reinforcement schedule. The effect of amphetamine alone depended on baseline rate and varied among individual rats. Ethanol had a depressant effect on response rates, but combinations of the two drug treatments produced rates that, in most rats, were higher than after any single drug or saline treatment. [ABSTRACT FROM AUTHOR]

We studied the neurotoxicological effects of high-dose toluene exposure by measuring neurotransmitter release from the striatum and spontaneous motor activity in freemoving Tokai High Avoider (THA) male rats. The rats were exposed to 1,000, 2,000, and 4,000ppm toluene for 4 hours. During the 4-hour exposure period and each one hour pre- and post-exposure periods, acetylcholine (ACh), 3, 4-dihydroxyphenylacetic acid (DOPAC), homovanilic acid (HVA) and 5-hydroxyindoleacetic acid (5-HIAA) in the microdialysate from kthe striatum of each rat were measured continuously using microdialysis. Simultaneously, spontaneous motor activity of each rat was monitored using an Aimex device. The amounts of neurotransmitters released and spontaneous motor activity showed similar changes for every concentration of toluene exposure during those periods. Although minimal changes in neurotransmitters and motor activity were observed in the 1,000 ppm group, increases in neurotransmitter release and motor activity were observed in the 2,000 ppm group during the entire exposure period and also in the 4,000 ppm group during the early period of exposure. On the other hand, decreases in neurotransmitter release and motor activity were observed in the 4,000 ppm group during the late period of exposure. These findings indicate that the striatum influences motor activity via changes in the amounts of neurotransmitters released during the period of high-dose toluene exposure. [ABSTRACT FROM AUTHOR]

In experimentally naive rats, nicotine reduced spontaneous locomotor activity in a dose-related manner. After a single pretreatment with nicotine, acute tolerance developed; this was shown by a shift of the dose-response curve, such that the dose of nicotine required to produce a given decrement in activity was multiplied by a factor of about 2.4. In a second experiment, a range of doses of nicotine was found to induce tolerance, but the dose inducing the maximum degree of tolerance was rather critical. The results demonstrated the importance of using a range of pretreatment and challenge doses when assessing tolerance to nicotine. However, frequently repeated doses were not necessary, since tolerance developed when nicotine was administered to rats only once in every 3 days. In terms of tolerance liability in rats, it seems that nicotine is not discriminable from other drugs upon which dependence can be established. [ABSTRACT FROM AUTHOR]

By means of a new automatic apparatus the influence of lysergic acid diethylamide (LSD) on spontaneous motor activity (SMA) was investigated in rats. Both the horizontal and vertical component of SMA were registered simultaneously at various time intervals after i.p. administration of the drug. A biphasic effect of LSD on both parameters was observed-SMA was stimulated in the first phase, while an inhibitory effect appeared with the increasing interval from the drug administration. The horizontal component was found to be more sensitive to the stimulatory effect while inhibition was more marked in the vertical activity. [ABSTRACT FROM AUTHOR]

A series of experiments were conducted to determine whether nicotine facilitates avoidance acquisition by enhancing consolidation or merely by stimulating performance. Sprague-Dawley albino rats were trained for 15 one-hour sessions in a discriminated leverpress avoidance situation with buzzer as a conditioned stimulus. More rats receiving nicotine, 0.4 mg/kg, i.p. immediately before each one-hour daily session (presession) reached a preset learning criterion than did saline controls, and rats receiving 0.1 mg/kg of nicotine performed better than controls but not as well as those receiving the higher nicotine dose. Rats given similar doses of quaternary nicotine bismethiodide in an identical presession experiment did not learn more proficiently than controls. Other groups of rats were given four doses of nicotine in photocell activity cages and the doses of nicotine which facilitated avoidance acquisition actually depressed spontaneous motor activity. Later studies in which rats were given 0.1 and 0.4 mg/kg nicotine or saline i.p. immediately after each session (postsession) showed that the drug also facilitates avoidance acquisition by this method; however, only the lower dose produced significant facilitation in this instance. Finally, rats were again trained with precession nicotine, but saline was substituted for nicotine beginning on session 16. No drug dissociation effect was seen. Thus the results of these studies strongly suggest that small doses of nicotine permanently facilitate the consolidating neural memory trace and do not enhance avoidance acquisition merely by stimulating performance. [ABSTRACT FROM AUTHOR]

The effect of d-amphetamine in combination with pentobarbital sodium, reserpine, chlorpromazine, meprobamate and chlordiazepoxide has been studied on spontaneous motor activity in male mice. d-Amphetamine together with CNS depressants produced a greater effect than amphetamine alone. [ABSTRACT FROM AUTHOR]

Effects of nonspecific opiate receptor antagonist naloxone in doses of 0.1, 0.5, 1.0, 5.0, 10.0 mg/kg on open field behavior and spontaneous motor activity were studied in male BALB/c and С57Bl/6 mice. Differently directed effects of naloxone on behavioral parameters of emotional-stress reaction in BALB/c and С57Bl/6 mice were observed. Naloxone increased motor activity in the open field test in BALB/c mice, but decreased it in С57Bl/6 mice. In the absence of stress, naloxone in the studied dose range did not affect spontaneous motor activity in С57Bl/6 mice, and significantly reduced activity in BALB/c mice in doses 0.5 and 1.0 mg/kg. [ABSTRACT FROM AUTHOR]

Background: Early motor development is characterized by progressive changes in general movements paralleled by a gradual organization of the four limbs' repertoire towards the midline, as shown by computerised movement analysis.Aims: Our aim was to test the performance of quantitative computerised kinematic indexes as predictors of post-term age in an independent cohort of typically developing subjects at fidgety age, tested cross-sectionally.Subjects: We selected twelve low risk term infants, who were video recorded between 9 and 20 weeks (fidgety age) during one spontaneous movements session.Study Design: We correlated post-term age with I)indexes of coordination including interlimb correlation of velocity and position, II)indexes of distance, including interlimb and limb-to- ground, both expressed as linear distance and as probability of midline limbs position III)indexes of global movement quality by calculating Hjorth's activity, mobility and complexity parameters. All indexes were calculated for both upper and lower limbs.Results: Significant positive correlations were found between post-term age and indexes of distance, and probability of occurrence of upper-limb antigravity patterns, and with both indexes of global movement quality. By combining linear and non-linear parameters related to the upper limb kinematics, we determined individual post-term age with a mean error of <1 week (5.2 days). No correlations were found between age and indexes of coordination.Conclusions: Quantitative computerised analysis of upper-limb movements is a promising predictor of post-term age in typically developing subjects at fidgety age. [ABSTRACT FROM AUTHOR]