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7823783 
Journal Article 
EFFECTS OF VARIOUS DURATIONS OF RESTRAINT STRESS ON THE TRACE-ELEMENT METABOLISM IN RAT-BRAIN REGIONS 
Saito, T; Fujimura, M; Itoh, T; Saito, K 
1995 
1 
Trace Elements and Electrolytes
ISSN: 0946-2104 
12 
2 
89-94 
English 
WOS:A1995QU97800007 
Changes in copper (Cu), zinc (Zn), manganese (Mn) and molybdenum (Mo) concentrations in 7 regions of the rat brain were determined just after 15, 30 or 60 min of restraint stress and 2 h after release from 60-min restraint stress to elucidate the effects of variations in the durations of restraint stress and release from stress on the metabolism of essential trace elements in the central nervous system. Cu and Zn concentrations were decreased significantly in the striatum, hippocampus, and cerebral cortex by short periods of restraint stress. Significant decreases of Mn and Mo concentrations depending on the duration of the reatraint stress were observed in the cerebellum, midbrain and thalamus, hippocampus, and cerebral cortex. Of the 4 regions in which decreases in Mn and Mo concentrations caused by restraint stress were observed, Mn and Mo levels in the midbrain and thalamus, and hippocampus, and Mo levels in the cerebral cortex returned to the control levels 2 h after release from 60-min stress while both metals in the cerebellum and Mn in the cerebral cortex were elevated significantly as compared to the control level. On the other hand, Cu and Zn levels in the striatum and hippocampus did not return to basal levels even 2 h after release from 60-min stress. Furthermore, additional stress-induced changes of those metal levels were observed in the regions where no changes were observed just after restraint stress. The plasma corticosterone concentration, determined as a criterion of stressful conditions, was elevated significantly just after 15 min of restraint stress, subsequently continued to increase and reached a level about 4-fold that of the control in the 60-min stress group. However, it returned to the basal level 2 h after release from the 60 min of restraint stress. These results suggest that changes in these trace elements in the brain regions may be closely related to the processes of neural activations induced by mild physiological stimuli and that the metabolisms of these metals are differently regulated according to each functional role in the central nervous system. 
TRACE ELEMENT METABOLISM; RESTRAINT STRESS; BRAIN; PLASMA CORTICOSTERONE