| N-pathway (CI-linked pathway) |
Respiration induced by the addition of NADH-generating substrates. Electrons are transferred from CI to CIII and then to CIV. |
| S-pathway (CII-linked pathway) |
Respiration induced by the addition of succinate and Rot. CI is inhibited by Rot while electrons can only be generated by CII, transferred to CIII and then to CIV. |
| NS-pathway (CI- and CII-linked pathways) |
Respiration induced by the addition of NADH-generating substrates and succinate without Rot. Combination of both pathways (usual pathway) whereby electrons move from both CI and CII, to CIII and then to CIV. |
| ROUTINE, R
|
ROUTINE respiration controlled by intrinsic energy demand. This represents energy demand under steady-state conditions. |
| LEAK, L
|
LEAK respiration caused by proton leak, proton slip, cation cycling, and electron leak. L is measured in the presence of reducing substrate(s) but absence of ADP or after enzymatic inhibition of the phosphorylation system by Omy. |
| OXPHOS, P
|
Respiration in the ADP-stimulated state of oxidative phosphorylation; OXPHOS capacity. |
| ET, E
|
Oxygen consumption in the non-coupled state at optimum uncoupler concentration, ET capacity. |
| ROX, Rox
|
Residual oxygen consumption, measured after inhibition of the ETS. |
| (E − P)/E
|
Relative E − P excess capacity, defines the limitation of OXPHOS capacity exerted by the phosphorylation system. |
| (P − L)/P
|
OXPHOS coupling efficiency, combining the effects of coupling and limitation by the phosphorylation system. |
