Intensive Care Unit (ICU) Biospecimen and Data Repository

Spare Respiratory Capacity (SRC)

时间窗: through study completion, an average of 2 months

This measurement indicates the capability of the cell to respond to an energetic demand as well as how closely the cell is to respiring to its theoretical maximum. The cell's ability to respond to demand can be an indicator of cell fitness or flexibility

ATP production-coupled Respiration

时间窗: upon admission

The decrease in oxygen consumption rate upon injection of the ATP synthase inhibitor oligomycin represents the portion of basal respiration that was being used to drive ATP production. Shows ATP produced by the mitochondria that contributes to meeting the energetic needs of the cell.

Maximal Respiration

时间窗: upon admission

The maximal oxygen consumption rate attained by adding the uncoupler FCCP. FCCP mimics a physiological "energy demand" by stimulating the respiratory chain to operate at maximum capacity, which causes rapid oxidation of substrates (sugars, fats, and amino acids) to meet this metabolic challenge. Shows the maximum rate of respiration that the cell can achieve.

Non-Mitochondrial Respiration

时间窗: through study completion, an average of 2 months

Oxygen consumption that persists due to a subset of cellular enzymes that continue to consume oxygen after the addition of rotenone and antimycin A. This is important to get an accurate measure of mitochondrial respiration.

Basal Respiration

时间窗: through study completion, an average of 2 months

Oxygen consumption used to meet cellular ATP demand resulting from mitochondrial proton leak. Shows energetic demand of the cell under baseline conditions.