Growth Cone Collapse and Neurite Retractions

• Published in: Journal of radiation research Vol. 49; no. 5; p. 481
• Main Authors: S. AL-JAHDARI, Wael, SUZUKI, Yoshiyuki, YOSHIDA, Yukari, NODA, Shin-ei, SHIRAI, Katsuyuki, SAITO, Shigeru, GOTO, Fumio, NAKANO, Takashi
• Format: Journal Article
• Language: English
• Published: Oxford Oxford University Press 01.09.2008
• ISSN: 0449-3060; 1349-9157

The growth cone is a structure at the terminal of a neurite that plays an important role in the growth of the neurite. The growth cone collapse assay is considered to be a useful method to quantify the effects of various factors on nerve tissue. Here, we investigated the effect of x-irradiation on growth cones and neurites and also the comparative radiosensitivity of different neurons. Dorsal root ganglia and sympathetic chain ganglion were isolated from day-8 and -16 chick embryos and cultured for 20 h. Neurons were then exposed to x-irradiation and morphological changes were quantitatively evaluated by growth cone collapse assay. Cell viability was examined using TUNEL and WST-1 assays. The results showed that radiation induced growth cone collapse and neurite retraction in a time- and exposure-responsive manner. Growth cone collapse, apoptosis and WST-1 assays showed that no significant difference between the neurons throughout the study period (p ≥ 0.5) after irradiation. Both types of day-8 neurons were more radio-sensitive than day-16 neurons (p ≤ 0.05). The time course of the growth cone collapse was significantly correlated with the apoptotic and cell viability responses at different irradiation doses. Growth cone collapse may represent a useful marker for assaying the effect of x-irradiation on normal cell neurons.