Effect of lanthanum chloride on apoptosis and cell cycle in primary cultured astrocytes of rat

Objective To study the effect of lanthanum chloride(LaCl3) on apoptosis and cell cycle in the primary cultured astrocytes of rat for exploring its mechanism of neurotoxicity.Methods The primary cultured astrocytes from neonate rat were separated and cultured,then exposed to 0,0.25,0.5 or 1.0 mmol/L of LaCl3 for 24h after purification and identification.The cell viability was determined by MTT assay,and the apoptosis and cell cycle were determined by flow cytometry.Results The cell viability in the astrocytes exposed to LaCl3 decreased significantly from 100%(as controls) to 53.31%(P0.01) with the increase of exposure dose of LaCl3,the rate of apoptosis increased significantly from 0.72% to 11.6%(P0.05),meanwhile,there were some abnormalities in cellular appearance.On the other hand,the percentage of cells in G1 phase was elevated significantly from 78.35% to 92.11%(P0.05),that in S phase reduced significantly from 6.19% to 1.53%(P0.05),and that in G2 phase decreased significantly from 15% to 7.09%(P0.05),which all were dose dependent.Conclusions The results suggested that LaCl3 exposure may induce apoptosis and abnormal cell cycle in cultured astrocytes,which might be the possible mechanism of neurotoxicity by LaCl3.