In mesial temporal lobe epilepsy (mTLE), the predominant form of epilepsy in adults, and in animal models of the disease, there is a conspicuous loss of the intracellular Ca(2+)-binding protein calbindin-D(28k) (CB) from granule cells (GCs) of the dentate gyrus. The role of this protein in nerve cell function is controversial, but here we provide evidence for its role in controlling Ca(2+) infl...