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Behavioural Tests (behavioural + test)
Selected AbstractsAltered sensorimotor development in a transgenic mouse model of amyotrophic lateral sclerosisEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 10 2004Julien Amendola Abstract Most neurodegenerative diseases become manifest at an adult age but abnormalities or pathological symptoms appear earlier. It is important to identify the initial mechanisms underlying such progressive neurodegenerative disease in both humans and animals. Transgenic mice expressing the familial amyotrophic lateral sclerosis (ALS)-linked mutation (G85R) in the enzyme superoxide dismutase 1 (SOD1) develop motor neuron disease at 8,10 months of age. We address the question of whether the mutation has an early impact on spinal motor networks in postnatal mutant mice. Behavioural tests showed a significant delay in righting and hind-paw grasping responses in mutant SOD1G85R mice during the first postnatal week, suggesting a transient motor deficit compared to wild-type mice. In addition, extracellular recordings from spinal ventral roots in an in vitro brainstem,spinal cord preparation demonstrated different pharmacologically induced motor activities between the two strains. Rhythmic motor activity was difficult to evoke with N -methyl- dl -aspartate and serotonin at the lumbar levels in SOD1G85R mice. In contrast to lumbar segments, rhythmic activity was similar in the sacral roots from the two strains. These results strongly support the fact that the G85R mutation may have altered lumbar spinal motor systems much earlier than previously recognized. [source] Cuticular hydrocarbons in a termite: phenotypes and a neighbour,stranger effectPHYSIOLOGICAL ENTOMOLOGY, Issue 3 2002Manfred Kaib Abstract The composition of cuticular hydrocarbons of different colonies of the fungus-growing termite Macrotermes falciger shows considerable intercolonial variation. Ordination, as well as cluster analyses, separate profiles into three distinct chemical phenotypes. Behavioural tests with major workers reveal no alarm behaviour or mortality in pairings of workers from the same colony but a full range from no alarm to overt aggression, with associated death, when individuals were paired from different colonies. The level of mortality increases with differences in the composition of cuticular hydrocarbons between colonies. However, no mortality occurs in pairings of individuals from neighbouring colonies belonging to different phenotypes. The data thus provide evidence for a ,neighbour,stranger' effect (so-called ,dear-enemy' phenomenon) in termites. [source] Conditional ablation of neurones in transgenic miceDEVELOPMENTAL NEUROBIOLOGY, Issue 3 2001Anthony R. Isles Abstract Conditional targeted ablation of specific cell populations in living transgenic animals is a very powerful strategy to determine cell functions in vivo. This approach would be of particular value to study the functions of distinct neuronal populations; however, the transgene of choice for conditional cell ablation studies in mice, the herpes simplex virus thymidine kinase gene, cannot be used to ablate neurones as its principal mode of action relies on cell proliferation. Here we report that expression of the E.coli nitroreductase gene (Ntr) and metabolism of the prodrug CB1954 (5-aziridin-1-yl-2-4-dinitrobenzamide) to its cytotoxic derivative can be used to conditionally and acutely ablate specific neuronal populations in vivo. As proof of principal, we have ablated olfactory and vomeronasal receptor neurones by expressing Ntr under the control of the olfactory marker protein (OMP) gene promoter. We demonstrate that following CB1954 administration, olfactory and vomeronasal receptor neurones expressing the transgene were selectively eliminated from the olfactory epithelium (OE), and projections to the olfactory bulb (OB) were lost. The functional efficacy of cell ablation was demonstrated using a highly sensitive behavioural test to show that ablated mice had lost the olfactory ability to discriminate distinct odors and were consequently rendered anosmic. Targeted expression of Ntr to specific neuronal populations using conventional transgenes, as described here, or by "knock-in" gene targeting using embryonic stem cells may be of significant value to address the functions of distinct neuronal populations in vivo. © 2001 John Wiley & Sons, Inc. J Neurobiol 47: 183,193, 2001 [source] Effect of N -Acetyl Cysteine against Aluminium-induced Cognitive Dysfunction and Oxidative Damage in RatsBASIC AND CLINICAL PHARMACOLOGY & TOXICOLOGY, Issue 2 2009Atish Prakash Chronic aluminium exposure induces oxidative stress and increases amyloid beta levels in vivo. The role of oxidative stress has been well-suggested in these cognitive problems. Therefore, the present study was designed to explore the possible role of N -acetyl cysteine against aluminium mediating cognitive dysfunction and oxidative stress in rats. Aluminium chloride (100 mg/kg, p.o.) was given to rats daily for 6 weeks. N -acetyl cysteine (per se; 50 and 100 mg/kg, i.p.) pre-treatment was given 30 min. before aluminium daily for 6 weeks. On the third (21st day) and sixth week (42nd day) of the study, various behavioural tests (Morris water maze and elevated plus maze task paradigms) and locomotion (photoactometer) were done to evaluate cognitive tasks. The rats were killed on the 43rd day following the last behavioural test, and various biochemical tests were performed to assess the extent of oxidative damage. Chronic aluminium chloride administration resulted in poor retention of memory in Morris water maze, elevated plus maze task paradigms and caused marked oxidative damage. It also caused a significant increase in the acetylcholinesterase activity. Chronic administration of N -acetyl cysteine significantly improved memory retention in tasks, attenuated oxidative damage and acetylcholinesterase activity in aluminium-treated rats. The study suggests a neuroprotective effect of N -acetyl cysteine against aluminium-induced cognitive dysfunction and oxidative damage. [source] Substance P excites globus pallidus neurons in vivoEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 7 2007Qiao-Ling Cui Abstract Substance P is a member of the neurokinin family. Previous studies have reported the existence of substance P and its high-affinity receptor, neurokinin-1 receptor, in globus pallidus. Employing in vivo extracellular recording combined with behavioural tests, the effects of substance P in globus pallidus of rats were studied. Micropressure ejection of the selective neurokinin-1 receptor agonist [Sar9,Met(O2)11] substance P increased the spontaneous firing rate of pallidal neurons in a concentration-dependent manner, with increases of 27.3% at 0.01, 33.4% at 0.03, 45.5% at 0.1, 38.4% at 0.3 and 36.4% at 1.0 mm. The selective neurokinin-1 receptor antagonist SR140333B prevented the excitatory effects induced by [Sar9,Met(O2)11] substance P. In behaving rats, we observed the postural effects of neurokinin-1 receptor activation in the globus pallidus. Consistent with electrophysiological results, unilateral microinjection of [Sar9,Met(O2)11] substance P (0.1 mm) led to a SR140333B-sensitive contralateral deflection in the presence of systemic haloperidol administration. Combining electrophysiological and behavioural findings, we concluded that substance P produces excitatory effects on globus pallidus neurons via neurokinin-1 receptors. [source] Evidence for RPE65-independent vision in the cone-dominated zebrafish retinaEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 7 2007Helia B. Schonthaler Abstract An enzyme-based cyclic pathway for trans to cis isomerization of the chromophore of visual pigments (11- cis -retinal) is intrinsic to vertebrate cone and rod vision. This process, called the visual cycle, is mostly characterized in rod-dominated retinas and essentially depends on RPE65, an all- trans to 11- cis -retinoid isomerase. Here we analysed the role of RPE65 in zebrafish, a species with a cone-dominated retina. We cloned zebrafish RPE65 and showed that its expression coincided with photoreceptor development. Targeted gene knockdown of RPE65 resulted in morphologically altered rod outer segments and overall reduced 11- cis -retinal levels. Cone vision of RPE65-deficient larvae remained functional as demonstrated by behavioural tests and by metabolite profiling for retinoids. Furthermore, all- trans retinylamine, a potent inhibitor of the rod visual cycle, reduced 11- cis -retinal levels of control larvae to a similar extent but showed no additive effects in RPE65-deficient larvae. Thus, our study of zebrafish provides in vivo evidence for the existence of an RPE65-independent pathway for the regeneration of 11- cis -retinal for cone vision. [source] Neuroanatomical specificity in the expression of the immediate early gene c-fos following expression of appetitive and consummatory male sexual behaviour in Japanese quailEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 7 2006M. Taziaux Abstract We investigated the neural sites related to the occurrence of appetitive (ASB) and consummatory (CSB) aspects of male sexual behaviour in Japanese quail. Castrated males treated with testosterone were exposed for 5 min to one of four experimental conditions: (i) free interaction with a female (CSB group); (ii) expression of rhythmic cloacal sphincter movements in response to the visual presentation of a female (ASB-F group); (iii) or a male (ASB-M group), and (iv) handling as a control manipulation. Brains were collected 90 min after the start of behavioural tests and stained by immunocytochemistry for the FOS protein. An increase in FOS expression was observed throughout the rostro-caudal extent of the medial preoptic nucleus (POM) in CSB males, whereas the view of a female (ASB-F) induced an increased FOS expression in the rostral POM only. In the CSB group, there was also an increase in FOS expression in the bed nucleus striae terminalis, and both the CSB and ASB-F groups exhibited increased FOS expression in aspects of the ventro-lateral thalamus (VLT) related to visual processing. Moreover, both the CSB and ASB-M groups showed increased FOS expression in the lateral septum. These data provide additional support to the idea that there is a partial anatomical dissociation between structures involved in the control of both aspects of male sexual behaviour and independently provide data consistent with a previous lesion study that indicated that the rostral and caudal POM differentially control the expression of ASB and CSB in quail. [source] Neuropathic pain is enhanced in ,-opioid receptor knockout miceEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 3 2006Xavier Nadal Abstract We have evaluated the possible involvement of ,-opioid receptor (DOR) in the development and expression of neuropathic pain. For this purpose, partial ligation of the sciatic nerve was performed in DOR knockout mice and wild-type littermates. The development of mechanical and thermal allodynia, as well as thermal hyperalgesia was evaluated by using the von Frey filament model, the cold-plate test and the plantar test, respectively. In wild-type and DOR knockout mice, sciatic nerve injury led to a neuropathic pain syndrome revealed in these nociceptive behavioural tests. However, the development of mechanical and thermal allodynia, and thermal hyperalgesia was significantly enhanced in DOR knockout mice. These results reveal the involvement of DOR in the control of neuropathic pain and suggest a new potential therapeutic use of DOR agonists. [source] Behavioural Assays to Model Cognitive and Affective Dimensions of Depression and Anxiety in RatsJOURNAL OF NEUROENDOCRINOLOGY, Issue 10 2008M. D. S. Lapiz-Bluhm Animal models have been used extensively to investigate neuropsychiatric disorders, such as depression, and their treatment. However, the aetiology and pathophysiology of many such disorders are largely unknown, which makes validation of animal models particularly challenging. Furthermore, many diagnostic symptoms are difficult to define, operationalise and quantify, especially in experimental animals such as rats. Thus, rather than attempting to model complex human syndromes such as depression in their entirety, it can be more productive to define and model components of the illness that may account for clusters of co-varying symptoms, and that may share common underlying neurobiological mechanisms. In preclinical investigations of the neural regulatory mechanisms linking stress to depression and anxiety disorders, as well as the mechanisms by which chronic treatment with antidepressant drugs may exert their beneficial effects in these conditions, we have employed a number of behavioural tests in rats to model specific cognitive and anxiety-like components of depression and anxiety disorders. In the present study, we review the procedures for conducting four such behavioural assays: the attentional set-shifting test, the elevated-plus maze, the social interaction test and the shock-probe defensive burying test. The purpose is to serve as a guide to the utility and limitations of these tools, and as an aid in optimising their use and productivity. [source] Differential effects of lorazepam on sleep and activity in C57BL/6J and BALB/cJ strain miceJOURNAL OF SLEEP RESEARCH, Issue 3 2009XIANGDONG TANG Summary Compared to C57BL/6 mice, BALB/c mice exhibit greater ,anxiousness' on behavioural tests of anxiety, and can show significantly longer sleep disruptions after exposure to anxiogenic situations. Relative to C57BL/6 mice, BALB/c mice also have reduced benzodiazepine (BZ) receptor densities in the brain and fivefold less BZ receptor density in the amygdala, a region important in anxiety and in the control of arousal. Lorazepam is a BZ receptor full agonist and has been used to treat both anxiety and insomnia. Differences between C57BL/6 and BALB/c mice raise the question of whether BZ agonists would impact sleep and activity differentially in the two strains. We examined the effects of two doses of lorazepam (0.5 and 1.5 mg kg,1) or saline alone (0.2 mL) on sleep and activity in C57BL/6 (n = 8) and BALB/c (n = 7) mice. Compared to saline, both doses of lorazepam significantly increased non-rapid eye movement (NREM) and reduced activity in both strains. In C57BL/6 mice, rapid eye movement (REM) was increased at both doses. In BALB/c mice, the 0.5 mg kg,1 dose had no significant influence on REM, whereas REM was reduced significantly after the 1.5 mg kg,1 dose. The results demonstrate significant differences between C57BL/6 and BALB/c mice in the effects of lorazepam on REM, whereas the effects on NREM and activity were similar. Strain differences in the number of BZ receptors in the amygdala, but not other brain regions, suggests possible site specificity in the effects of lorazepam on REM. These differences in BZ-binding sites in the amygdala could be a significant factor in differences in the sleep response between C57 and BALB/c mice. [source] Effect of N -Acetyl Cysteine against Aluminium-induced Cognitive Dysfunction and Oxidative Damage in RatsBASIC AND CLINICAL PHARMACOLOGY & TOXICOLOGY, Issue 2 2009Atish Prakash Chronic aluminium exposure induces oxidative stress and increases amyloid beta levels in vivo. The role of oxidative stress has been well-suggested in these cognitive problems. Therefore, the present study was designed to explore the possible role of N -acetyl cysteine against aluminium mediating cognitive dysfunction and oxidative stress in rats. Aluminium chloride (100 mg/kg, p.o.) was given to rats daily for 6 weeks. N -acetyl cysteine (per se; 50 and 100 mg/kg, i.p.) pre-treatment was given 30 min. before aluminium daily for 6 weeks. On the third (21st day) and sixth week (42nd day) of the study, various behavioural tests (Morris water maze and elevated plus maze task paradigms) and locomotion (photoactometer) were done to evaluate cognitive tasks. The rats were killed on the 43rd day following the last behavioural test, and various biochemical tests were performed to assess the extent of oxidative damage. Chronic aluminium chloride administration resulted in poor retention of memory in Morris water maze, elevated plus maze task paradigms and caused marked oxidative damage. It also caused a significant increase in the acetylcholinesterase activity. Chronic administration of N -acetyl cysteine significantly improved memory retention in tasks, attenuated oxidative damage and acetylcholinesterase activity in aluminium-treated rats. The study suggests a neuroprotective effect of N -acetyl cysteine against aluminium-induced cognitive dysfunction and oxidative damage. [source] Animal colour vision , behavioural tests and physiological conceptsBIOLOGICAL REVIEWS, Issue 1 2003ALMUT KELBER ABSTRACT Over a century ago workers such as J. Lubbock and K. von Frisch developed behavioural criteria for establishing that non-human animals see colour. Many animals in most phyla have since then been shown to have colour vision. Colour is used for specific behaviours, such as phototaxis and object recognition, while other behaviours such as motion detection are colour blind. Having established the existence of colour vision, research focussed on the question of how many spectral types of photoreceptors are involved. Recently, data on photoreceptor spectral sensitivities have been combined with behavioural experiments and physiological models to study systematically the next logical question: ,what neural interactions underlie colour vision ?,This review gives an overview of the methods used to study animal colour vision, and discusses how quantitative modelling can suggest how photoreceptor signals are combined and compared to allow for the discrimination of biologically relevant stimuli. [source] | |||||||||||||