lecture 5 - gluconeogenesis & response to trauma

Question 1

Which organs are capable of undergoing gluconeogenesis?

Answer 1

Liver (mainly), kidneys

Question 2

What are the 3 key precursors for gluconeogenesis?

Answer 2

1. Lactate from muscle glycolysis/anaerobic metabolism
2. glycerol from TAG lipolysis in adipose
3. alanine from muscle proteins

Question 3

Why does insulin resistance cause increased gluconeogenesis?

Answer 3

The effects of insulin are unopposed, so glucagon dependent processes such as gluconeogenesis are upregulated

Question 4

Why does alcoholism impair gluconeogenesis?

Answer 4

Alcohol metabolism consumes significant amounts of NAD, which is also needed to process lactate into pyruvate for gluconeogenesis. Thus, alcoholics may have low pyruvate and develop hypoglycaemia.

Question 5

What hormones drive the metabolic response to trauma?

Answer 5

Adrenaline, glucagon, cortisol, cytokines

Question 6

What are the 3 key phases of the metabolic response to injury?

Answer 6

Shock phase, catabolic phase, anabolic phase

Question 7

What are the features of the catobolic phase following trauma?

Answer 7

Increased metabolic rate, weight loss, muscle wasting

Question 8

Why is there increased metabolic requirements following trauma?

Answer 8

Energy is required for tissue repair and the immune response - a catabolic state allows stored fuels to be utilised