title: Comparison of the radiosensitivities of neurons and glial cells derived from the same rat brain.
abstract: Non-proliferating cells, such as mature neurons, are generally believed to be more resistant to X-rays than proliferating cells, such as glial and vascular endothelial cells. Therefore, the late adverse effects of radiotherapy on the brain have been attributed to the radiation-induced damage of glial and vascular endothelial cells. However, little is known about the radiosensitivities of neurons and glial cells due to difficulties in culturing these cells, particularly neurons, independently. In the present study, primary dissociated neurons and glial cultures were prepared separately from the hippocampi and cerebrum, respectively, which had been obtained from the same fetal rat on embryonic day 18. X-irradiations of 50 Gy were performed on the cultured neurons and glial cells at 7 and 21 daysin vitro(DIV). The cells were fixed at 24 h after irradiation. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling was then performed to measure the apoptotic indices (AIs). The AIs of non-irradiated and irradiated neurons at 7 DIV were 23.7±6.7 and 64.9±4.8%, and those at 21 DIV were 52.1±17.4 and 44.6±12.5%, respectively. The AIs of non-irradiated and irradiated glial cells at 7 DIV were 5.8±1.5 and 78.4±3.3% and those at 21 DIV were 9.6±2.6 and 86.3±4.9%, respectively. Glial cells and neurons were radiosensitive at 7 DIV. However, while glial cells were radiosensitive at 21 DIV, neurons were not.
authors.affiliation: Department of Radiation Oncology, Gunma University Graduate School of Medicine, Maebashi, Gunma 371-8511, Japan.
authors.forename: Shigehiro
authors.initials: S
authors.lastname: Kudo
authors.affiliation: Department of Radiation Oncology, Gunma University Graduate School of Medicine, Maebashi, Gunma 371-8511, Japan.
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Suzuki
authors.affiliation: Department of Radiation Oncology, Gunma University Graduate School of Medicine, Maebashi, Gunma 371-8511, Japan.
authors.forename: Shin-Ei
authors.initials: SE
authors.lastname: Noda
authors.affiliation: Department of Neurobiology and Behavior, Gunma University Graduate School of Medicine, Maebashi, Gunma 371-8511, Japan.
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Mizui
authors.affiliation: Department of Radiation Oncology, Gunma University Graduate School of Medicine, Maebashi, Gunma 371-8511, Japan.
authors.forename: Katsuyuki
authors.initials: K
authors.lastname: Shirai
authors.affiliation: Department of Radiation Oncology, Gunma University Graduate School of Medicine, Maebashi, Gunma 371-8511, Japan.
authors.forename: Masahiko
authors.initials: M
authors.lastname: Okamoto
authors.affiliation: Department of Radiation Oncology, Gunma University Graduate School of Medicine, Maebashi, Gunma 371-8511, Japan.
authors.forename: Takuya
authors.initials: T
authors.lastname: Kaminuma
authors.affiliation: Gunma University Heavy Ion Medical Center, Maebashi, Gunma 371-8511, Japan.
authors.forename: Yukari
authors.initials: Y
authors.lastname: Yoshida
authors.affiliation: Department of Neurobiology and Behavior, Gunma University Graduate School of Medicine, Maebashi, Gunma 371-8511, Japan.
authors.forename: Tomoaki
authors.initials: T
authors.lastname: Shirao
authors.affiliation: Department of Radiation Oncology, Gunma University Graduate School of Medicine, Maebashi, Gunma 371-8511, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Nakano
keywords: apoptosis; glia; neuron; radiation