NEET PG Medical – 2019 – Question – 37
Hyperammonaemia inhibit TCA cycle by depleting?
a) succinate
b) a keto glutarate
c) malate
d) fumarate
Show Answer
Correct Answer – B
Answer: B. a keto glutarate
The urea cycle and the citric acid cycle are independent cycles but are linked.
To detoxify ammonia in hyperammonemia, more glutamate is required. This glutamate is formed from c-ketoglutarate.
a-ketoglutarate ?Transamination ?glutamate + NH4+? glutamine.
Thus excessive a–ketoglutarate is consumed leading to decrease availability of a–ketoglutarate for TCA cycle.
