Inhibitory effect of lithium chloride on mouse thymocyte apoptosis

This study investigates the effect of lithium chloride (LiCI) on mouse thymocyte apoptosis. A primary culture of mouse thymocytes was preincubated with LiCI (from 5 to 500μmol/L) before exposure to dexamethasone (DEX), the apoptosis inducer. With 100 μmol/L of LiCI, apoptotic cell death induced by DEX was almost completely prevented as determined by flow cytometric analysis, termnal deoxynucleotidy Itransferase (TdT)-mediated dUTP nick end labeling (TUNEL) assay and DNA laddering assay. The results show that the DEX-induced increment of caspase-3 activity in thymocytes is completely eliminated by LiCI preincubati on. The resul ts suggest that LiCI may protect Balb/c mouse thymocytes from apoptosis induced by glucocorticoid in a dose-dependent matter.