A researcher conducts a study to evaluate the morphological changes of various cerebral pathologies using live animal models. In an experiment, histopathological examination of the brain after an inciting event shows neurons with intensely eosinophilic cytoplasm and condensed basophilic nuclei. Serial biopsies are obtained to evaluate progressive changes. Which of the following is most likely to be seen in the affected brain area in the subsequent weeks?

Question

A researcher conducts a study to evaluate the morphological changes of various cerebral pathologies using live animal models.  In an experiment, histopathological examination of the brain after an inciting event shows neurons with intensely eosinophilic cytoplasm and condensed basophilic nuclei.  Serial biopsies are obtained to evaluate progressive changes.  Which of the following is most likely to be seen in the affected brain area in the subsequent weeks?

Quizplus · Accepted Answer

11ec160b_39cb_ee7a_9249_9ddcbea06003_MD0001_00 The histopathological findings of neurons with shrunken, basophilic nuclei and intensely eosinophilic cytoplasm (red neurons) are indicative of irreversible neuronal damage. In response to irreversible injury and neuronal death, astrocytes proliferate at the site of injury to restore tissue integrity (a role analogous to fibroblasts outside the CNS). This process is called astrocytosis (or gliosis) and is a universal response of the CNS to severe damage. As astrocytes proliferate, they replace lost neurons, compensate for their volume, and over time form a closely connected, firm meshwork called a gliotic scar. (Choices A and E) Although both vascular hyalinization and amyloid deposition can lead to neural injury, both would show accumulations of extracellular eosinophilic material on histopathological examination. (Choice B) Fibroblast migration to a site of injury occurs in most of the peripheral tissues of the body, but not the CNS, where tissue repair is a function of astrocytes. (Choice D) Irreversibly injured neurons do not hypertrophy; they undergo cellular necrosis. Microglia are responsible for phagocytizing the resulting dead cells and debris. Educational objective: CNS injury is associated with astrocyte hypertrophy and proliferation (gliosis). This process leads to the formation of a glial scar, which compensates for the volume loss that occurs after neuronal death.

A Researcher Conducts a Study to Evaluate the Morphological Changes