Related Experiment Video
Updated: Jul 11, 2026
A Behavioral Test Battery for the Repeated Assessment of Motor Skills, Mood, and Cognition in Mice
Published on: March 2, 2019
Behavioral effects of subchronic inorganic manganese exposure in rats
1Department of Public Health, University of Szeged Faculty of Medicine, Dóm toŕ 10, Szeged, Hungary. vezer@puhe.szote.u-szeged.hu
Background:
Manganese, an essential micronutrient, is a potential neurotoxicant in prolonged overexposure. Parkinson-like syndrome, motor deficit, disturbed psychomotor development are typical signs of neuropathological alterations due to Mn in humans.
Methods:
Young adult rats, in three groups of 16 each, received 15 and 59 mg/kg b.w. MnCl(2), (control: distilled water) via gavage for 10 weeks, and were kept for further 12 weeks. Correlation of MnCl(2) exposure to body and organ weights, neurobehavioral effects (spatial memory, exploratory activity, psychomotor performance, pre-pulse inhibition), and histopathological changes (gliosis) was sought.
Results:
By the end of treatment, Mn accumulated in blood, cortex, hippocampus, and parenchymal tissues. Body and organ weights were reduced in high dose rats. All treated rats showed hypoactivity, decreased memory performance, and diminished sensorimotor reaction. In the dentate gyrus of these, GFAP immunoreactivity increased. During the post-treatment period, body weight of the high dose group remained decreased, locomotor activity returned to control, but the lasting effect of MnCl(2) could be revealed by amphetamine.
Conclusion:
Using complex methodology, new data were obtained regarding the relationship between the long-term effects of MnCl(2) at neuronal and behavioral level.
Insights
Manganese (Mn) overexposure in rats caused neurotoxicity, affecting behavior and memory. Long-term effects were observed even after exposure ceased, indicating persistent neurological changes.
Area of Science:
- Neuroscience
- Toxicology
- Environmental Health
Background:
- Manganese (Mn) is an essential micronutrient but a potential neurotoxicant with prolonged overexposure.
- Human exposure to Mn can lead to Parkinson-like symptoms, motor deficits, and psychomotor disturbances.
Purpose of the Study:
- To investigate the long-term neurobehavioral and histopathological effects of manganese chloride (MnCl2) exposure in young adult rats.
- To establish the relationship between MnCl2 exposure levels and observed neurological alterations.
Main Methods:
- Rats were exposed to two doses of MnCl2 (15 and 59 mg/kg b.w.) or distilled water (control) via gavage for 10 weeks.
- Neurobehavioral tests assessed spatial memory, exploratory activity, psychomotor performance, and pre-pulse inhibition.
- Histopathological analysis focused on glial fibrillary acidic protein (GFAP) immunoreactivity in the dentate gyrus to detect gliosis.
Main Results:
- Manganese accumulated in blood, cortex, hippocampus, and parenchymal tissues.
- High-dose MnCl2 exposure reduced body and organ weights, induced hypoactivity, impaired memory, and diminished sensorimotor responses.
- Increased GFAP immunoreactivity in the dentate gyrus indicated gliosis; some effects persisted post-exposure, detectable with amphetamine challenge.
Conclusions:
- This study provides new data on the dose-dependent, long-term neurotoxic effects of manganese chloride at both neuronal and behavioral levels.
- The findings highlight the potential for lasting neurological damage following chronic manganese overexposure.
