Carnosine chelates [Zn²⁺]_i rises mobilized from intracellular sites.

<p>(A) Time course of DTDP-mediated [Zn²⁺]_i rises in cortical glial cells. Newport Green loaded astrocytes (white circle) were imaged upon a 20 min incubation in a physiological buffer, HCSS, and during a 20 min exposure to DTDP (100 µM), a compound that mobilizes Zn²⁺ from intracellular Zn²⁺-binding proteins. In parallel experiments, Newport Green loaded glial cultures (black circles) were incubated in HCSS plus carnosine (20 mM) for 20 min and subsequently exposed to DTDP plus carnosine for other 20 min. The graph shows the time course of DTDP-induced Newport Green fluorescence changes (expressed as ratio of F_X/F₀) in carnosine treated and untreated glial cultures. Traces show mean (± SEM) fluorescence changes deriving from 3 different experiments for each condition. (B) Bar graph depicts the overall cytosolic [Zn²⁺]_i rise expressed as area under the curve after the DTDP exposure. (*) indicates differences between control and carnosine treated astrocytes (<i>p</i><0.001).