Back to Search
Start Over
In vivo measurement of presynaptic Zn2+ release during forebrain ischemia in rats.
- Source :
-
Biological & pharmaceutical bulletin [Biol Pharm Bull] 2006 Apr; Vol. 29 (4), pp. 821-3. - Publication Year :
- 2006
-
Abstract
- Previous studies have suggested that during forebrain ischemia, considerable Zn2+ is released from synaptic vesicles of gultamatergic neuronal terminals and accumulates in hippocampal CA1 pyramidal neurons, leading to delayed neuronal death. However, since a time lag exists between the accumulation of Zn2+ and the occurrence of ischemia and there are conflicting reports about the amount of Zn2+ released, the level of released Zn2+ during ischemia in vivo is still unclear. In this study, we investigated the temporal change of extracellular Zn2+ in the hippocampal CA1 area using microdialysis and the accumulation of Zn2+ in hippocampal CA1 neurons with TSQ staining in rats with a transient forebrain ischemia. The level of extracellular Zn2+ in the CA1 area increased transiently reaching a peak 15 min after occlusion, then decreased with time, returning to the basal level 15 min after reperfusion. In addition, at this peak, the level of extracellular Zn2+ was about twice the basal level. Assessment of the intracellular Zn2+ in hippocampal neurons with TSQ revealed that Zn2+ accumulate at 24 h, but not 0 and 6 h after ischemia. These results suggest that, although the synaptic vesicular Zn2+ is released into the synaptic cleft during ischemia in vivo, the amount of released Zn2+ might not be so excessive, and it does not accumulate in hippocampal CA1 pyramidal neurons immediately after ischemia.
- Subjects :
- Animals
Fluorescent Dyes
Glutamic Acid metabolism
Hippocampus cytology
Hippocampus drug effects
Hippocampus metabolism
Male
Microdialysis
Pyramidal Cells drug effects
Pyramidal Cells metabolism
Rats
Rats, Wistar
Receptors, Presynaptic drug effects
Brain Ischemia metabolism
Prosencephalon blood supply
Receptors, Presynaptic metabolism
Zinc metabolism
Subjects
Details
- Language :
- English
- ISSN :
- 0918-6158
- Volume :
- 29
- Issue :
- 4
- Database :
- MEDLINE
- Journal :
- Biological & pharmaceutical bulletin
- Publication Type :
- Academic Journal
- Accession number :
- 16595927
- Full Text :
- https://doi.org/10.1248/bpb.29.821