Abstract
Quantification of myocardial glucose uptake by positron emission tomography with [18F]fluorodeoxyglucose (FDG) requires the 'lumped constant' (LC), which corrects the difference of affinity between glucose and FDG to glucose transporters and phosphorylating system. Since LC was introduced, it has been considered to be constant. However, this has recently been questioned. To elucidate the constancy of LC by other than radioisotope techniques, the accumulation rate of sugar phosphates (d[SP]/dt) was measured in isolated, perfused rat hearts by 31P NMR spectroscopy with 2- deoxyglucose (DG). We postulate α as the affinity of DG to transporters and the phosphorylating system relative to that of glucose. Theoretically, α is equivalent to LC. We determined α by measuring d[SP]/dt at DG concentration ([DG]) = 10, 7, 5, and 3 mmol/l, keeping the total of glucose concentration ([glucose]) and [DG] to 10 mmol/l. When the glucose uptake was enhanced by insulin (10 mU/ml) or stunning, calculated, was reduced (insulin stimulated, 0.15; stunning, 0.19) compared with the control (0.59). These results indicate that LC can be evaluated by methods without radiolabeled tracers and is smaller when glucose uptake is augmented.
| Original language | English (US) |
|---|---|
| Journal | American Journal of Physiology - Heart and Circulatory Physiology |
| Volume | 276 |
| Issue number | 1 45-1 |
| State | Published - Jan 1999 |
| Externally published | Yes |
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Keywords
- Insulin
- Myocardial stunning
- Nuclear magnetic resonance spectroscopy
ASJC Scopus subject areas
- Physiology
- Physiology (medical)
Cite this
Lumped constant for deoxyglucose is decreased when myocardial glucose uptake is enhanced. / Hashimoto, Katsuji; Nishimura, Tsunehiko; Imahashi, Ken Ichi; Yamaguchi, Hitoshi; Hori, Masatsugu; Kusuoka, Hideo.
In: American Journal of Physiology - Heart and Circulatory Physiology, Vol. 276, No. 1 45-1, 01.1999.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Lumped constant for deoxyglucose is decreased when myocardial glucose uptake is enhanced
AU - Hashimoto, Katsuji
AU - Nishimura, Tsunehiko
AU - Imahashi, Ken Ichi
AU - Yamaguchi, Hitoshi
AU - Hori, Masatsugu
AU - Kusuoka, Hideo
PY - 1999/1
Y1 - 1999/1
N2 - Quantification of myocardial glucose uptake by positron emission tomography with [18F]fluorodeoxyglucose (FDG) requires the 'lumped constant' (LC), which corrects the difference of affinity between glucose and FDG to glucose transporters and phosphorylating system. Since LC was introduced, it has been considered to be constant. However, this has recently been questioned. To elucidate the constancy of LC by other than radioisotope techniques, the accumulation rate of sugar phosphates (d[SP]/dt) was measured in isolated, perfused rat hearts by 31P NMR spectroscopy with 2- deoxyglucose (DG). We postulate α as the affinity of DG to transporters and the phosphorylating system relative to that of glucose. Theoretically, α is equivalent to LC. We determined α by measuring d[SP]/dt at DG concentration ([DG]) = 10, 7, 5, and 3 mmol/l, keeping the total of glucose concentration ([glucose]) and [DG] to 10 mmol/l. When the glucose uptake was enhanced by insulin (10 mU/ml) or stunning, calculated, was reduced (insulin stimulated, 0.15; stunning, 0.19) compared with the control (0.59). These results indicate that LC can be evaluated by methods without radiolabeled tracers and is smaller when glucose uptake is augmented.
AB - Quantification of myocardial glucose uptake by positron emission tomography with [18F]fluorodeoxyglucose (FDG) requires the 'lumped constant' (LC), which corrects the difference of affinity between glucose and FDG to glucose transporters and phosphorylating system. Since LC was introduced, it has been considered to be constant. However, this has recently been questioned. To elucidate the constancy of LC by other than radioisotope techniques, the accumulation rate of sugar phosphates (d[SP]/dt) was measured in isolated, perfused rat hearts by 31P NMR spectroscopy with 2- deoxyglucose (DG). We postulate α as the affinity of DG to transporters and the phosphorylating system relative to that of glucose. Theoretically, α is equivalent to LC. We determined α by measuring d[SP]/dt at DG concentration ([DG]) = 10, 7, 5, and 3 mmol/l, keeping the total of glucose concentration ([glucose]) and [DG] to 10 mmol/l. When the glucose uptake was enhanced by insulin (10 mU/ml) or stunning, calculated, was reduced (insulin stimulated, 0.15; stunning, 0.19) compared with the control (0.59). These results indicate that LC can be evaluated by methods without radiolabeled tracers and is smaller when glucose uptake is augmented.
KW - Insulin
KW - Myocardial stunning
KW - Nuclear magnetic resonance spectroscopy
UR - http://www.scopus.com/inward/record.url?scp=0032898376&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0032898376&partnerID=8YFLogxK
M3 - Article
C2 - 9887025
AN - SCOPUS:0032898376
VL - 276
JO - American Journal of Physiology
JF - American Journal of Physiology
SN - 0363-6135
IS - 1 45-1
ER -