Morphological changes in cortical neurons and glia of rats in the context of global cerebral ischemia – reperfusion injury and its treatment with p-tyrosol

Aim. To investigate morphological alterations in neurons and glial cells in the cerebral cortex using a rat model of total transient global cerebral ischemia (GCI) and to evaluate the neuroprotective effects of p-tyrosol.
Materials and methods. Experiments were performed on Wistar rats (n = 30), randomly divided into three groups: sham-operated, GCI control, and GCI with p-tyrosol treatment. The glioneuronal elements of the cerebral cortex were analyzed by light and transmission electron microscopy combined with a quantitative morphometric assessment.
Results. In the GCI group, a significant reduction in neuron density was observed. Surviving neurons showed a marked decrease in the relative volume of membrane-bound organelles, accompanied by an increase in lipofuscin, lysosomes, and vacuoles. Administration of p-tyrosol after GCI enhanced neuronal survival.
Conclusion. For the first time in this rat model of GCI, structural and ultrastructural changes of cortical neurons and glial cells in rats were characterized, confirming the validity of the model. Neuroprotective effects of p-tyrosol in the context of GCI were demonstrated at both the light-microscopic and ultrastructural levels.

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