Figure 1.

A decrease in external Na⁺ or an increase in internal Na⁺ elevates intracellular Ca²⁺ in Bergmann glia, potentially implicating the sodium-calcium Ca²⁺ exchanger (NCX) mechanism. (A) Fluorescence intensity image (left, fura-2 AM, λ_x = 380 nm) of the cerebellar slice. White circle, region of interest (Bergmann glia cell body); PN, Purkinje cell. (B, C) Intracellular Ca²⁺ concentration reversibly increases in response to application of an Na⁺-free bath solution (B) or to intracellular whole-cell loading of bulk-loaded cells with a high Na⁺ solution (C). Modified from Kirischuk and others (1997).