Analysis of concurrent glucose consumption by the hexose monophosphate shunt, glycolysis, and the polyol pathway in the crystalline lens.
A method based on 13C-NMR spectroscopy is described, in which the metabolism of [13C2]glucose was assessed in intact rat lenses. By analysing the ratio of 13C3/(13C2 + 13C3) lactate, a quantitative measurement of the hexose monophosphate shunt (HMPS) activity could be derived. Similarly, measurements of the time-dependent increase of lactate and sorbitol permitted the determination of the activity of the Embden-Meyerhof pathway and the polyol pathway, respectively. This method offers significant advantages over other biochemical and spectroscopic methods and allows for the first time a direct correlation between the activities of the polyol pathway and the HMPS.
Howe Laboratory of Ophthalmology, Harvard Medical School, Boston, MA.
H M
HM
Cheng
J
J
Xiong
G
G
Tanaka
C
C
Chang
A A
AA
Asterlin
J B
JB
Aguayo
D000818:Animals; D005947:Glucose / Q000378:metabolism*; D006019:Glycolysis; D066298:In Vitro Techniques; D007773:Lactates / Q000378:metabolism; D007908:Lens, Crystalline / Q000378:metabolism*; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D010427:Pentose Phosphate Pathway; D051381:Rats; D011919:Rats, Inbred Strains; D013012:Sorbitol / Q000378:metabolism
D007773:Lactates; D013012:Sorbitol; D005947:Glucose