The effect of prenatal X‐irradiation on the developing cerebral cortex of rats. II: A quantitative assessment of glial cells in the somatosensory cortex

Abstract

The developing central nervous system is known to be highly vulnerable to X-irradiation. Although glial cells are involved in various brain functions, knowledge on the effects of X-irradiation on glial cells is limited. Therefore, the purpose of the present study was to evaluate the effects of prenatal X-irradiation on glial cells. Pregnant Wistar rats were exposed to X-irradiation at a dose of 1.0 Gy on day 15 of gestation. Their offspring were examined at 7 weeks of age. The forebrain weight of X-irradiated rats was significantly lower than that of the age-matched controls. Histological quantification with stereology of the somatosensory cortex (SC) revealed no significant difference in the numerical density of glial cells between the X-irradiated and control rats. However, the glial cells in the X-irradiated animals had significantly larger nuclear size. We had previously reported that a similar X-irradiation paradigm resulted in no significant change in the numerical density of neurons in the SC. According to the results of the present study, there were no significant differences in the glial cell-to-neuron ratios between the X-irradiated and control animals. Taken together, it is speculated that prenatal X-irradiation has an equal effects on the numerical densities of glial cells and neurons.

Spatial Frequency-Based Analysis of Mean Red Blood Cell Speed in Single Microvessels: Investigation of Microvascular Perfusion in Rat Cerebral Cortex

“…In this vein, an improvement or enhancement of endothelial cell growth potentially improves CNS cell development and neural connections, which may be a possible therapeutic target to prevent development defects in the prenatal exposed subjects. On the other hand, it has been shown that a density of cortical neurons and astroglia was preserved in the postnatal rats following X-ray irradiation (1.0 Gy) despite a decrease in cortical thickness [45], [46]. These findings suggest that the local energy demand per unit volume was similar to that of non-exposed subjects.…”

BDNF overexpression in mouse hippocampal astrocytes promotes local neurogenesis and elicits anxiolytic-like activities

“…To confirm the possibility that BDNF overexpression in hippocampal astrocytes produced anxiolytic-/antidepressant-like effects through neurogenesis-dependent and neurogenesis-independent mechanisms, we examined whether the ablation of neurogenesis through X-irradiation, which does not affect glial cells density or hippocampal morphology, 1, 26 blocked or attenuated the behavioral responses observed in lenti-BDNF mice in a new batch of animals (Figure 4; Supplementary Figure S5). …”

Deciphering glial scar after spinal cord injury

“…X-Ray irradiation can affect neurons and glial cells, although neurons are less sensitive to X-rays than are glial cells. A single-dose of X-ray irradiation with a D0 for X rays of 1.45 Gy does not damage nerve cells, especially oligodendrocytes, thereby promoting axon regeneration [ 94 , 95 ]. Kalderon and Fuks [ 96 ] found that X-rays can inhibit the death and degeneration of neurons and at least partially improve the recovery of motor function after spinal cord transection in rats.…”