Search results for "Nmri mice"
showing 10 items of 10 documents
Previous Training in the Water Maze
1999
It has been shown that acquisition rates in the water maze vary across strains of mice, although the differential effects of previous experience in this spatial task have been scarcely evaluated. The aim of the present study was to evaluate the effects of training in the water maze at an early age (2 months) in two strains of mice (NMRI and C57BL) using a longitudinal study. Mice with or without previous training were tested when they were 6 months, and retested when 10 months old. The results showed that trained NMRI mice performed better than all the other groups, both at test and retest, indicating that previous training had more beneficial effects in NMRI than in C57BL mice. These resul…
Effects of acute administration of bupropion on behavior in the elevated plus-maze test by NMRI mice
2004
Bupropion attenuates some symptoms of nicotine abstinence, although its effects on anxiety are unclear. The present study investigates acute effects of bupropion (5, 10, 20 and 40 mg/kg) on anxiety as expressed in the elevated plus-maze test in male NMRI mice. Given the influence of locomotion in this test, effects of bupropion were also evaluated in an actimeter. Spontaneous motor activity remained significantly increased in mice treated with 10, 20 and 40 mg/kg of bupropion during the 60 min recorded. Results from the elevated plus-maze showed that 20 mg/kg increased total arm entries and 40 mg/kg increased total and open arm entries. Although the increase in the number of visits to the o…
Effects of Early Training and Nicotine Treatment on the Performance of Male NMRI Mice in the Water Maze
2004
This research aimed to evaluate the effect of nicotine treatment and prior training on a spatial learning task in differently aged NMRI male mice. In a longitudinal study, mice were randomly assigned to one of 14 experimental groups receiving different combinations of chronically injected nicotine (0.35 mg/kg) administered for 10 days (5 days before and during 5 days acquisition of task) or control treatments and training in the water maze at different ages. The mice displayed shorter escape latencies when evaluated at 6 and 10 months than when tested in this task at 2 months for the first time, demonstrating that early training preserves performance in the water maze up to 8 months after t…
Effects of housing and nicotine on shuttle-box avoidance in male NMRI mice
2005
The present study aimed to evaluate whether housing condition could interact with nicotine administration in influencing the acquisition of a two-way active avoidance task. Male NMRI mice were either group- or individually housed for 30 days and, after this period, evaluated both in the actimeter and, 24h later, in the elevated plus-maze. On the basis of the percentage of time spent in the open arms of the plus-maze, both group- and individually housed mice were sub-classified into three groups with high, moderate or low anxiety baseline levels. Effects of nicotine on the acquisition of the two-way active avoidance task was assessed in each of these groups of mice using an automated shuttle…
Behavioral effects of combined environmental enrichment and chronic nicotine administration in male NMRI mice
2013
Abstract Environmental enrichment (EE) is an experimental paradigm which provides sensory, social, physical and cognitive stimulation for rodents. Experimental evidence indicates that this type of housing induces different neurobiological and behavioral changes. However, few studies have evaluated the consequences of combined exposure to an enriched environment and nicotine administration during a critical period of development such as adolescence. Taking into account previous studies, it can be hypothesized that a chronic treatment with nicotine would modulate the effects of rearing animals in enriched environments. In the current study, our main aim was to evaluate the effects of EE and c…
Behavioral impact of experience based on environmental enrichment: Influence of age and duration of exposure in male NMRI mice
2020
Prior studies have suggested that short periods of exposure to environmental enrichment (EE) in rodents induce physiological and behavioral effects. In the present study, our aim was to evaluate if the impact of experiences based on EE could be modulated by the age of onset and the developmental period of exposure. NMRI male mice (n = 64) were exposed to EE or standard environment (SE) and behavioral changes (anxiety, exploration, memory and social interaction) were evaluated. Groups compared were: (a) SE: exposure to SE on post-natal day (PND) 28 and lasting 6 months; (b) EE-6: exposure to EE on PND 28 and lasting 6 months; (c) EE-4: exposure to EE on PND 91 and lasting 4 months; (d) EE-2:…
Radiolabeled DNase, a potential indicator for noninvasive detection of tissue damage
1983
Pancreatic DNase I was labeled with 131I or fluorescamine and injected IV into NMRI mice bearing a sarcoma 180. Of the injected tracer, 1.5%-2% was found to accumulate per g tumor. In sections of tumor tissue DNase was localized in damaged cells in solid and necrotic tumor regions. This binding is most probably due to specific interaction of DNase with actin, an ubiquitous cytoskeletal protein. Two-component blood clearance with a rapid first component (two-thirds of applied radioactivity) was observed. The labeled tumor could easily be visualized by gamma camera imaging. The findings suggest DNase to be a potent radiopharmaceutical for imaging damaged tissue, occurring in malignant tumors …
Effect of polybrominated biphenyls on bromobenzene lethality in mice.
1977
Polybrominated biphenyls (PBBs) are inducers of hepatic microsomal cytochrome P450 and P1 450 in rats and mice. The purpose of this study was to determine, in mice, the effect of PBBs on the lethality of the hepatotoxin bromobenzene. Female NMRI mice were administered a single ip injection of 150 mg/kg PBBs and other mice received phenobarbital (PB), 100 mg/kg daily for 3 days, or 3‐methylcholanthrene (MC), 20 mg/kg daily for 3 days. At 24 hr after PB or MC and 24, 48, and 96 hr after PBBs animals received 3,150 mg/kg bromobenzene ip (LD85) and the time to death was recorded. Both PB and MC enhanced bromobenzene lethality and decreased the median time to death (LT50) from 23 hr in controls …
Motor activity in group-housed and isolated mice with short and long attack latencies: Effects of scopolamine
2002
Isolation-induced behavioral changes are well described in mice, although few studies have investigated the involvement of the cholinergic system in these effects. It has also been suggested that mice that display short or long attack latencies show differences in their reactions to a novel environment. The purpose of the present study was, first, to investigate locomotor activity in grouped and isolated mice that displayed short or long attack latencies and, second, to evaluate locomotor activity to determine whether it was affected interactively by differential housing and scopolamine treatment. Two experiments were performed in which NMRI mice, either isolated or group housed, were used …
Effects of nicotine on motor activity, passive avoidance and plus-maze behavior in aged NMRI and C57BL mice
2002
The aim of the present study is to evaluate the effects of nicotine (0.35 and 0.175 mg/kg) on locomotor activity, passive avoidance and plus maze behavior in aged mice of two strains (C57BL and NMRI). In a first experiment, aged mice of these strains were injected with nicotine or saline and immediately afterwards were put on the actimeter. Results showed that nicotine significantly decreased locomotor activity in C57 mice. In a second experiment, nicotine was administered before training and retention sessions of a passive avoidance task. Results indicated that 0.175 mg/kg nicotine significantly increased entry latency in aged NMRI mice but had no effects on C57 mice. In the last experimen…