THE EFFECT OF X-RADIATION ON CEREBELLAR GRANULE CELLS GROWN IN CULTURE. GANGLIOSIDE GM1 NEUROPROTECTIVE ACTIVITY.

GUELMAN, L. R; ZIEHER, L. M.; FISZMAN, M. L.

NEUROCHEMISTRY INTERNATIONAL

Elsevier

Año: 1996 vol. 29 p. 521 - 527

0197-0186

In this paper we describe the effects of X-radiation on the viability of cerebellar granule cells grown in culture. Cell cultures were exposed to X-rays 2 h after plating and then grown for 1-7 days. Two days after X-ray exposure with a dose-range of 0.1-2 Gy (acute effect), a significant decrease in neuronalnumber was observed. The magnitude of the lethal effect was directly correlated to the dose of X-ray applied. When the interval between plating and irradiation was increased, the acute lethal effect of X-rays decreased. 3H-thymidine incorporation was maximal during the first 24 h in vitro and decreased to nearlyblank levels, after 72 h. In some experiments, cells present in each culture dish were counted at day 2 and at day 7. We observed that the number of cells present in sham-irradiated cultures decreased from day 2 to day 7, reflecting cell death after several days in vitro. The cell loss observed in X-irradiated cultures was significantly greater as compared with sham-irradiated cultures, confirming the deleterious effect of X-ray on cell survival. This effect was completely prevented by GM 1 (6.5, 10 and 30 #M) added 48 h after X-rayexposure, but not 1 h after plating. We conclude that X-rays induce two different effects: an acute effect related to impaired DNA synthesis which is very active during the first 24 h in vitro, and a long-term effect owing to a sublethal damage in the surviving neuronal population.