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Old 08-22-2012
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Help Question in biochem

Does anybody know the reason why deficiency of glucose-6-phosphatase leads to lactate acidosis?

Thanks a lot!
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Old 08-22-2012
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I'm guessing...
It's a defect in the final step of gluconeogeneis (von Girke's disease)... so I'm assuming things get backed up to the point where there is excess pyruvate available for lactate dehydrogenase to convert into lactate effectively causing lactic acidosis... and not to mention all that ketone production due to lack of glucose available for the body to use.
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Old 08-22-2012
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Quote:
Originally Posted by belindalimm View Post
Does anybody know the reason why deficiency of glucose-6-phosphatase leads to lactate acidosis?

Thanks a lot!
glucose 6 phosaphatase is the last enzyme in glycogenolysis (and also in gluconeogenesis)

so in deficiency of enzyme ....
1) in liver....again glycogen synthesis takes place and more glycogen deposits in liver.... hypoglycemia
as glucose 6 phosphatase is only present in liver......glycogen cannot be a source for glucose production in other organs...
2) in muscle-----severe fasting hypoglycemia and excess glycogen lead to phosphorylation of glycogen( as there is glycogen phosphorylase in muscle and no glucose 6 phosphatase) till glucose 6 phosphate..and there after gllycolysis takes place leading to excess lactate( as glycogenolysis takes place in fasting conditions mainly...so anaerobic metabolism)...and also excess lactate can revert back to glucose by gluconeogenesis but as glucose 6 phosphatase deficient it cannot further proceed and leading to lactic acidosis......and also hyperuricemia too
hope it understands...
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