Table 3 Inhibition of Ca2+-uptake activity. The purified CV-fraction P0E and the purified ER-fraction P1E were tested for sensitivity of Ca2+-uptake to Tg (22 μM), BHQ (200 μM), CMA (40 μM) and Sr2+ (30–60 μM) as indicated. nd: not determined. Data are means ± SD. The number of independent experiments is given in brackets.