Histopathological Assessments of Animal Models of Cerebral Ischemia - Animal Models of Acute Neurological Injuries: Injury and Mechanistic Assessments - page 10

ischemia damages more than 90% of CA1 neurons, the dorsolateral
striatal neurons, and about 10% of neocortical neurons, whereas
20 min of ischemia leads to delayed neuronal death in more than
30% of neocortical neurons and also extends delayed neuronal
death to neurons in the CA3 and DG regions.
Figure 4 illustrates typical histopathological changes in the
hippocampal regions after transient cerebral ischemia in the 2
vessel-occlusion (with hypotension) forebrain ischemia (2VO)
model in rat. Male Wistar rats were subjected to either sham-surgery
without ischemia, or 10 min of ischemia followed by 7 days of rep-
erfusion, respectively. Paraffi n-embedded coronal sections (10 mm)
were photographed by light microscopy. Selective neuronal death
is evident in more than 80% of pyramidal neurons in the CA1
region of the hippocampus after 10 min of cerebral ischemia in the
2VO model.

5. Potential
Technical
Diffi culties
and Pitfalls

Even though histology is routinely used by various laboratories, it
is relatively long procedure. Every step in the procedure is important.
High temperature during tissue processing or longer time in cleansing
agents can make tissue brittle and damage tissue integrity.

References

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4. Bancroft JD, Stevens A (1996) Theory and prac-
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5. Smith ML et al (1984) Models for studying
long-term recovery following forebrain ischemia
in the rat. 2. A 2-vessel occlusion model. Acta
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