Table 3 Hydrolytic activities of mink erythrocyte membrane fraction, (Na++K+)-activated ATPase activity in the absence and the presence of ouabain, pNPPase activity in the presence of K+ or Na+, Ca+-activated ATPase activity in the presence of Ca+ or EDTA ± calmodulin and pNPPase activity in the presence of Ca+ ± ATP. Number of determinations in brackets.
1998 | 1999 | |
|---|---|---|
nmol·(mg protein)-1·min-1 ± SEM | ||
(Na++K+)-ATPase | 18.4 ± 0.9 (9) | 15.6 ± 2.3* (7) |
(Na++K+)-ATPase + ouabain | 14.5 ± 2.1 (7) | 9.6 ± 1.4* (7) |
K+-pNPPase | 12.7 ± 0.8 (4) | 11.3 ± 1.4 (3) |
Na+-pNPPase | 11.6 ± 2.1 (3) | 10.2 ± 0.2 (3) |
Ca2+-ATPase | ||
Activity in the presence of Ca2+ | 22.5 ± 1.2 (7) | n.d. |
Activity in the presence of Ca2++calmodulin | 19.8 ± 1.8 (7) | 37.8 ± 12.8 (4) |
Activity in the presence of EDTA | 17.3 ± 1.6 (5) | n.d. |
Activity in the presence of EDTA+calmodulin | 24.6 ± 1.9 (5) | 23.4 ± 4.7 (4) |
Ca2+-pNPPase (- ATP) | 7.4 ± 0.1 (3) | n.d. |
Ca2+-pNPPase (+ ATP) | 6.4 ± 0.1 (3) | n.d. |