TABLE 3.
Inhibition of Epo-stimulated increase in [Ca2+]i through TRPC3-F4
HEK 293T cells were transfected with BFP-TRPC3, BFP-TRPC3-F4 (Y226F/Y555F/Y648F/Y674F), BFP-TRPC3-Y674F, BFP-TRPC3-Y555F/Y648F, or BFP-TRPC3-Y226F and Epo-R. Fura Red-loaded cells were treated with 40 units/ml Epo. [Ca2+]i (mean ± S.E. in nm) was measured at base line and by monitoring over 20 min after Epo stimulation. Percentage increase (% Inc) above base line (mean ± S.E.) = peak [Ca2+]i/base-line [Ca2+]i × 100%, minus 100% (base line). n, number of individual cells studied.
|
Transfection
|
Stimulation
|
[Ca2+]i
|
% Inc
|
n
|
||
|---|---|---|---|---|---|---|
| Base line | Peak | |||||
| nm | % | |||||
| TRPC3 + Epo-R | PBS | 33 ± 2 | 47 ± 2 | 43 ± 5a | 16 | |
| Epo | 34 ± 1 | 113 ± 4a | 243 ± 15 | 23 | ||
| TRPC3-F4 + Epo-R | PBS | 36 ± 2 | 52 ± 2 | 44 ± 5a | 16 | |
| Epo | 36 ± 1 | 75 ± 3 | 108 ± 6a | 27 | ||
| TRPC3-Y674F + Epo-R | PBS | 30 ± 1 | 43 ± 1 | 43 ± 6a | 6 | |
| Epo | 31 ± 1 | 105 ± 2 | 238 ± 10 | 9 | ||
| TRPC3-Y555F Y648F + Epo-R | PBS | 30 ± 1 | 41 ± 2 | 37 ± 3a | 6 | |
| Epo | 32 ± 1 | 102 ± 3 | 215 ± 10 | 8 | ||
| TRPC3-Y226F + Epo-R | PBS | 32 ± 1 | 45 ± 3 | 41 ± 6a | 6 | |
| Epo | 34 ± 2 | 62 ± 2 | 86 ± 7a | 9 | ||
a
A significant difference from Epo-stimulated cells expressing wild type TRPC3 (p < 0.0001).