Figure 3.

No effects of huntingtin proteins and PRE084 on mitochondrial calcium responses. Mitochondrial Ca²⁺ concentrations were measured in PRE084-treated and in huntingtin protein-overexpressing cells as described in the Materials and Methods. (a and b) Representative traces of mitochondrial Ca²⁺ concentrations ([Ca²⁺]_mito) in PC6.3 cells expressing FL huntingtin constructs having 17 (17QFL) and 75 polyglutamine (75QFL) repeats and employing stimulations with 100 nM bradykinin. C, control plasmid pcDNA-expressing cells. Panel a is without pretreatment and panel b is pretreatment for 20 h with 0.3 μM PRE084. There were no significant changes in [Ca²⁺]_mito. between controls and PRE084-pretreated cells or after expressing of the mutant huntingtin proteins. (c and d) Summary histograms. Values are means±S.D., n=4. There was a tendency to higher [Ca²⁺]_mito following PRE084 treatment but these were not statistically significant from controls