Mrc. Schetinger et al., Pre-conditioning to global cerebral ischemia changes hippocampal acetylcholinesterase in the rat, BIOC MOL B, 47(3), 1999, pp. 473-478
This study shows the effect of transient global cerebral ischemia (ISC) on
hippocampal acetylcholinesterase (AChE) activity. Naive adult Wistar rats r
eceived either a brief (2 min) or a long (10 min) ischemic episode by the f
our-vessel occlusion method. Pre-conditioned rats received double ischemia:
a 10 min episode inflicted 24 h after a 2 min event, a condition known to
confer cytoprotection to CA(1) pyramidal cells of hippocampus. 2 min of isc
hemia caused an increase in acetylcholinesterase activity both immediately
and 30 min after the episode, however enzyme activity was significantly dec
reased after 24 h of reperfusion. 10 min of ischemia caused an increase in
activity both 60 min and 24 h after ischemia. Conversely, pre-conditioned r
ats displayed lower activity both immediately and 60 min after ischemia. Ou
r results suggest that: a) neuronal death, that follows 10 min of ischemia,
is associated to a late increase in acetylcholinesterase activity; b) pre-
conditioning is related to diminished acetylcholinesterase activity. This i
s in agreement with previous evidence that acetylcholinesterase inhibition
and maintenance of acetylcholine levels are beneficial for cell surviving a
fter cerebral ischemia.