Albumin protects cultured cerebellar granule neurons against zinc neurotoxicity

In this study, we have investigated the role of albumin in zinc-induced neurotoxicity of cultured rat cerebellar granule neurons. ZnCl2 induces cerebellar granule cell death in a time- and concentration-dependent manner and albumin in serum affords a significant protection against zinc-induced neurotoxicity. We further measured intracellular zinc concentrations in the presence or absence of albumin. The results showed that exogenously added ZnCl2 induced an increase in intracellular zinc concentrations in a concentration-dependent fashion in albumin-free buffer. However, in the presence of albumin, it dramatically decreased ZnCl2-induced elevation of intracellular zinc concentrations. These results indicate that albumin protects against zinc-induced neurotoxicity by blocking extracellular zinc uptake by neurons.