Summary for P2X responses in C8-B4 cells
| Experimental observation | C8-B4 cell condition | Analysis of changes | |||
| Resting (−LPS) | Activated (+ LPS) | Activated plus amitriptyline | Fold change (resting vs. activated) | Fold change (activated vs. activated plus amitriptyline) | |
| P2X4 mRNA levelsab | 0.21 ± 0.02 | 0.35 ± 0.02 | 0.17 ± 0.005 | 1.6 | 0.6 |
| Total P2X4 protein levelsc | 0.5 ± 0.2 | 0.5 ± 0.1 | 0.5 ± 0.2 | 1 | 1 |
| IATP (−pA/pF)d | 0 | 3.6 ± 0.5 | 1.5 ± 0.2 | ND | 0.4 |
| Surface P2X4 protein levelse | 1 | 3.5 ± 1 | 1.7 ± 0.2 | 3.5 | 0.5 |
| P2X4/LAMP1 colocalizationf | 0.7 ± 0.06 | 0.4 ± 0.02 | 0.8 ± 0.09 | 0.6 | 2.0 |
| Experimental observation | C8-B4 cell condition | Analysis of changes | |||
| Resting (−LPS) | Activated (+ LPS) | Activated plus amitriptyline | Fold change (resting vs. activated) | Fold change (activated vs. activated plus amitriptyline) | |
| P2X4 mRNA levelsab | 0.21 ± 0.02 | 0.35 ± 0.02 | 0.17 ± 0.005 | 1.6 | 0.6 |
| Total P2X4 protein levelsc | 0.5 ± 0.2 | 0.5 ± 0.1 | 0.5 ± 0.2 | 1 | 1 |
| IATP (−pA/pF)d | 0 | 3.6 ± 0.5 | 1.5 ± 0.2 | ND | 0.4 |
| Surface P2X4 protein levelse | 1 | 3.5 ± 1 | 1.7 ± 0.2 | 3.5 | 0.5 |
| P2X4/LAMP1 colocalizationf | 0.7 ± 0.06 | 0.4 ± 0.02 | 0.8 ± 0.09 | 0.6 | 2.0 |
The n numbers for each experimental group are provided in the text and figures. ND, not determinable (point 3 above).
Expressed relative to HPRT mRNA levels as measured by qPCR (the mean ± SEM data are presented in Fig. 3).
These data are for this direct comparison (n = 8). Another eight experiments where P2X4 was compared to other P2X subunit transcripts are shown in Fig. 3.
Expressed relative to β actin band intensities from Western blot analysis (Fig. 4).
Currents evoked by 100 µM ATP measured at −60 mV (Fig. 2). In the −LPS condition, most cells did not respond to ATP, and the remainder showed negligible ATP-evoked currents. When averaged across all −LPS C8-B4 cells, the ATP-evoked current was essentially 0, precluding the calculation of a fold-change in IATP.
As measured by surface biotinylation and expressed as normalized to the −LPS condition (Fig. 9).
Colocalization was assessed using the Pearson’s correlation coefficient (see Data analysis in Materials and methods and Fig. 9). Values between 0.5 and 1.0 are considered to represent meaningful colocalization.