Chapter 6 - Ischemia-reperfusion

Question 1

Injury during tissue ischemia

Answer 1

FIGURE 6.1

Question 2

Significance of MPTP during ischemia-reperfusion

Answer 2

Mitochondrial membrane permeability transition pore - low pH prevents MPTP opening - high ROS opens MPTP –> necrotic cell death

Question 3

Role of TNF alpha in cell apoptosis

Answer 3

Activated macrophages release TNF alpha –> NF kappa B pathway –> apoptosis

Question 4

Injury during reperfusion

Answer 4

FIGURE 6.2

Question 5

Reactive oxygen species in normal and in ischemia

Answer 5

normal: O- cleared by superoxide dismutase and then by catalase Ischemia: ROS generation high and overwhelms compensation –> positive feedback for more ROS then MPTP opening

Question 6

Higher risk for ischemia reperfusion in the limbs

Answer 6

Muscle - 4 hours bone - 4 days

Question 7

Cut off for intervening in compartment syndrome pressure

Answer 7

30 mmHg

Question 8

Biomarkers for compartment syndrome

Answer 8

MMP 1, 2, 3, 9 Neutrophil gelatinase associated lipocalin (NGAL)

Question 9

GI ischemia-reperfusion secondary hit

Answer 9

Bacterial translocation

Question 10

Systemic effects of AKI

Answer 10

FIGURE 6.3

Question 11

Ischemic preconditioning benefit

Answer 11

unclear shows promise only in benchtop research