Page 184 - BIOCHEMISTRY II
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• If blood glucose levels exceeds certain limits (average 180 mg/dl),
glucose will increase in glomerular filterate and exceeds the
capacity of tubular enzymes to reabsorb it. Thus glucose appears
in urine (glycosuria).
• This limit is called renal threshold for glucose re-absorption: It is
the blood glucose level above which glucose appears in urine
(average 180 mg/dl).
• Low renal threshold: where glucose appears in urine even when
blood glucose levels are low (may be just 100 mg/dl). This occurs
in:
– Normally in some people due to defective tubular enzymes for
glucose reabsorption.
– In 20% of pregnant women.
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