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Righting Reflex (righting + reflex)
Selected AbstractsDisease progression of human SOD1 (G93A) transgenic ALS model ratsJOURNAL OF NEUROSCIENCE RESEARCH, Issue 1 2006Arifumi Matsumoto Abstract The recent development of a rat model of amyotrophic lateral sclerosis (ALS) in which the rats harbor a mutated human SOD1 (G93A) gene has greatly expanded the range of potential experiments, because the rats' large size permits biochemical analyses and therapeutic trials, such as the intrathecal injection of new drugs and stem cell transplantation. The precise nature of this disease model remains unclear. We described three disease phenotypes: the forelimb-, hindlimb-, and general-types. We also established a simple, non-invasive, and objective evaluation system using the body weight, inclined plane test, cage activity, automated motion analysis system (SCANET), and righting reflex. Moreover, we created a novel scale, the Motor score, which can be used with any phenotype and does not require special apparatuses. With these methods, we uniformly and quantitatively assessed the onset, progression, and disease duration, and clearly presented the variable clinical course of this model; disease progression after the onset was more aggressive in the forelimb-type than in the hindlimb-type. More importantly, the disease stages defined by our evaluation system correlated well with the loss of spinal motor neurons. In particular, the onset of muscle weakness coincided with the loss of approximately 50% of spinal motor neurons. This study should provide a valuable tool for future experiments to test potential ALS therapies. © 2005 Wiley-Liss, Inc. [source] Systemic Administration of Arecoline Reduces Ethanol-Induced Sleeping Through Activation of Central Muscarinic Receptor in MiceALCOHOLISM, Issue 1 2010Yan-Ping Sun Background:, Epidemiological evidence of co-use of alcohol and areca nuts suggests a potential central interaction between arecoline, a major alkaloid of areca and a muscarinic receptor agonist, and ethanol. Moreover, the central cholinergic system plays an important role in the depressant action of ethanol and barbiturates. The purpose of this study was to investigate the effects of arecoline on pentobarbital- and ethanol-induced hypnosis in mice. Methods:, Male ICR mice were tested for locomotor activity following acute systemic administration of ethanol alone, arecoline alone, or ethanol plus arecoline. For the loss of the righting reflex (LORR) induced by pentobarbital and ethanol, sleep latency and sleeping duration were evaluated in mice treated with arecoline alone or the combination of arecoline and scopolamine or methscopolamine. Results:, Ethanol (1.0 to 3.0 g/kg, i.p.) reduced locomotor activity significantly and a declining trend was observed after treatment with arecoline (0.25 to 1.0 mg/kg, i.p.), but there were no synergistic effects of ethanol and arecoline on locomotor activity. The experiments on LORR demonstrated that arecoline (0.125 to 1.0 mg/kg, s.c.) shortened the duration of sleeping induced by ethanol (4.0 g/kg, i.p.), but not pentobarbital (45 mg/kg, i.p.). In addition, alterations of sleep latency were not obvious in both pentobarbital- and ethanol-induced LORR. Statistical analyses revealed that scopolamine (centrally acting), but not methscopolamine (peripherally acting), could antagonize the effect of arecoline on the duration of ethanol-induced LORR in mice. Conclusions:, These results suggest that central muscarinic receptor is a pharmacological target for the action of arecoline to modulate ethanol-induced hypnosis. [source] Different Sensitivity to Ethanol in Alcohol-Preferring sP and -Nonpreferring sNP RatsALCOHOLISM, Issue 11 2000Giancarlo Colombo Background and Objectives Clinical research has proposed that initial sensitivity to ethanol may be negatively correlated with levels of subsequent ethanol intake; consistently, alcohol-preferring P rats were found to be less sensitive to the ataxic and sedative/hypnotic effects of ethanol than -nonpreferring NP rats. The present study investigated the initial sensitivity to the ataxic and sedative/hypnotic effects of ethanol and to the sedative/hypnotic effects of pentobarbital and diazepam in selectively bred Sardinian alcohol-preferring sP and -nonpreferring sNP rats. Methods: In experiment 1, time to lose (onset) and regain (sleep time) the righting reflex after the acute intraperitoneal (ip) administration of 3.0 and 3.5 g/kg ethanol were measured in sP and sNP rats. In experiment 2, sP and sNP rats were required to perform a motor coordination task on a Rota-Rod after the acute intragastric administration of 2.0, 2.5, and 3.0 g/kg ethanol. Experiment 3 assessed onset and sleep time in sP and sNP rats after the acute injection of pentobarbital (40 mg/kg; ip) and diazepam (15 and 20 mg/kg; ip). Results: In experiment 1, sP rats took shorter times to lose the righting reflex and regained this reflex over longer periods of time and at lower blood ethanol levels than sNP rats. In experiment 2, ethanol affected motor coordination to a greater extent in sP than sNP rats. In contrast, results from experiment 3 showed that sP and sNP rats were not differentially sensitive to the sedative/hypnotic effects of pentobarbital and diazepam. Conclusions: The results of experiments 1 and 2 suggest that sP rats possess a genetically determined, greater sensitivity to the motor impairing and sedative/hypnotic effects of ethanol than sNP rats. Although caution should be adopted before hypothesizing any comparison to humans, these results may feature sP rats as an experimental model of those subsets of human alcoholics with initial high sensitivity to ethanol challenges. Finally, the results of experiment 3 suggest a minimal involvement of the benzodiazepine and barbiturate recognition sites in the differential sensitivity to ethanol of sP and sNP rats. [source] RESEARCH: Zopiclone (Cyclopyrrolone): A Novel Hypnosedative; Hypnosedation Caused by Zopiclone Does Not Impair Memory-Learning in Albino MiceCNS: NEUROSCIENCE AND THERAPEUTICS, Issue 5 2010Uma Kadam SUMMARY Objectives: To evaluate hypnosedative action of Zopiclone by using animal models for hypnosis and sedation (anxiolysis); and to further evaluate whether this hypnosedation impairs memory-learning in albino mice like conventional hypnosedatives. Methods: For evaluation of hypnosedation, following experiments were performed in albino mice: (1) righting reflex test, (2) pentobarbitone sleeping time potentiation, (3) open field apparatus behavior, and (4) elevated plus maze performance. For evaluation of effects on impairment of memory-learning, elevated plus maze retention test was performed in albino mice. Results: Zopiclone (7.5 mg/kg p.o.) did not inhibit the righting reflex. Significant (P < 0.001) potentiation of pentobarbitone sleeping time and increase in exploration in open field apparatus was observed. Elevated plus maze performance also showed significant (P < 0.01) increase in number of entries to open arm at the same time significant (P < 0.02) increase in time spent in open arm was observed. Elevated plus maze retention test showed significant (P < 0.01) increase in transfer latency on second day of experiment. Conclusions: Zopiclone (7.5 mg/kg p.o.) has selective hypnosedative activity but not CNS-depressant activity similar to BZDs. Hypnosedative action of Zopiclone does not impair memory-learning in albino mice like conventional hypnosedatives. [source] Minimal aberrant behavioral phenotypes of neuroligin-3 R451C knockin miceAUTISM RESEARCH, Issue 3 2008Kathryn K. Chadman Abstract Neuroligin-3 is a member of the class of cell adhesion proteins that mediate synapse development and have been implicated in autism. Mice with the human R451C mutation (NL3), identical to the point mutation found in two brothers with autism spectrum disorders, were generated and phenotyped in multiple behavioral assays with face validity to the diagnostic symptoms of autism. No differences between NL3 and their wildtype (WT) littermate controls were detected on measures of juvenile reciprocal social interaction, adult social approach, cognitive abilities, and resistance to change in a spatial habit, findings which were replicated in several cohorts of males and females. Physical and procedural abilities were similar across genotypes on measures of general health, sensory abilities, sensorimotor gating, motor functions, and anxiety-related traits. Minor developmental differences were detected between NL3 and WT, including slightly different rates of somatic growth, slower righting reflexes at postnatal days 2,6, faster homing reflexes in females, and less vocalizations on postnatal day 8 in males. Significant differences in NL3 adults included somewhat longer latencies to fall from the rotarod, less vertical activity in the open field, and less acoustic startle to high decibel tones. The humanized R451C mutation in mice did not result in apparent autism-like phenotypes, but produced detectable functional consequences that may be interpreted in terms of physical development and/or reduced sensitivity to stimuli. [source] | |||||||||||||