McArdle

[sonofababinski]

I was just wondering if someone could explain a hallmark finding for McArdle disease: A flat venous lactate curve with normal rise in ammonia levels during exercise?

Thank you in advance!!

---

Members don't see this ad.

 

[bsizzle44]

The deficient enzyme is glycogen phosphorylase in the muscle, thus you will not be able to break down glycogen and use glucose for ATP production. Since there is no glucose, it will not be possible to create pyruvate from glycolysis, and subsequently lactate from pyruvate. So, in this case, we will see no increase in lactic acid as we would expect when we exercise.

 

[sonofababinski]

The deficient enzyme is glycogen phosphorylase in the muscle, thus you will not be able to break down glycogen and use glucose for ATP production. Since there is no glucose, it will not be possible to create pyruvate from glycolysis, and subsequently lactate from pyruvate. So, in this case, we will see no increase in lactic acid as we would expect when we exercise.

thank you soo much!! and if possible, could you also explain the ammonia rise?