Effects of Insulin on Blood Glucose Entry and Removal Rates in Man

Ga, Reichard; Ag, Jacobs; Kimbel, Philip; Nj, Hochella; Weinhouse, Sidney

doi:10.2337/diab.9.6.447

Cited by 12 publications

(4 citation statements)

References 3 publications

(3 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This recycled label is indistinguishable from the original by the GC/C/IRMS technique. Although estimates of the contribution of recycled material to plasma glucose concentration have been made,15–17 these have been in the fasted state, and it is not expected that these estimates are valid under the conditions of the IVGTT. The evidence from this study is that, for the purposes of comparing the two tracers used, recycling mechanisms are not important.…”

Section: Resultsmentioning

confidence: 99%

Measurement of insulin sensitivity indices using ¹³C‐glucose and gas chromatography/combustion/isotope ratio mass spectrometry

Clapperton

Coward

Bluck

2002

Rapid Comm Mass Spectrometry

View full text Add to dashboard Cite

Important aspects of glucose metabolism can be quantified by using the minimal model of glucose kinetics to interpret the results of intravenous glucose tolerance tests. The power of this methodology can be greatly increased by the addition of stable isotopically labelled tracer to the glucose bolus dose. This allows the separation of glucose disposal from endogenous glucose production and also increases the precision of the estimates of the physiological parameters measured. Until now the tracer of choice has been deuteriated glucose and the analytical technique has been gas chromatography/mass spectrometry (GC/MS). The consequence of this choice is that nearly 2 g of labelled material are needed and this makes the test expensive. We have investigated the use of (13)C-labelled glucose as the tracer in combination with gas chromatography/combustion/isotope ratio mass spectrometry (GC/C/IRMS) as the analytical technique. This methodology offers superior analytical precision when compared with the conventional method and so the amount of tracer used, and hence the cost, can be reduced considerably. Healthy non-obese male volunteers were recruited for a standard intravenous glucose tolerance test (IVGTT) protocol but 6,6-(2)H-glucose and 1-(13)C-glucose were administered simultaneously. Tracer/tracee ratios were derived from isotope ratio measurements of plasma glucose using both GC/MS and GC/C/IRMS. The results of these determinations indicated that the two tracers behaved identically under the test protocol. The combination of these results with plasma glucose and insulin concentration data allowed determination of the minimal model parameters S*g and S*i. The parameter relating to insulin-assisted glucose disposal, S*i, was found to be the same in the two techniques, but this was not the case for the non-insulin-dependent parameter S*g.

show abstract

Section: Resultsmentioning

confidence: 99%

Measurement of insulin sensitivity indices using ¹³C‐glucose and gas chromatography/combustion/isotope ratio mass spectrometry

Clapperton

Coward

Bluck

2002

Rapid Comm Mass Spectrometry

View full text Add to dashboard Cite

show abstract

“…Lactate is probably the most important product of glucose catabolism that is not exclusively intracellular, and its importance as a source for recycling glucose carbon in monogastric animals has been demonstrated (Reichard et al 1963;Waterhouse and Keilson 1969;Forbath and Hetenyi 1970). In fed sheep, lactate carbon enters the oxaloacetate pool in the liver along with substantial quantities of carbon from propionate and amino acids (Bergman, Roe, and Kon 1966;Leng, Steel, and Luick 1967;Judson and Leng 1968;Reilly and Ford 1971).…”

Section: Discussionmentioning

confidence: 99%

Estimation of the Total Entry Rate and Resynthesis of Glucose in Sheep Using Glucoses Uniformly Labelled With 14C and Variously Labelled With 3H

Judson¹,

Leng²

1972

Aust. Jnl. Of Bio. Sci.

View full text Add to dashboard Cite

Comparisons have been made of [6_ 3H]-, [3-3H]-, and [2-3H]glucose with [U-14C]glucose for measuring parameters of glucose metabolism in sheep given their daily ration in 24 equal amounts at hourly intervals. The specific radioactivity (R) of plasma glucose was measured at frequent intervals from 0 to 10 hr and 0 to 32 hr after the start of a constant infusion. or single injection, of mixtures of these isotopes respectively.Estimates of glucose pool size by consideration of either the initial rectilinear slope (monoexponential analysis) or the multiexponential components of the log R-time curve after single injections of [3H} and [14C]glucose were similar.The mean irreversible loss of plasma glucose estimated by using [3-3H}, and [2-3H]glucose was approximately 79, 70, and 103 respectively. Further release of tritium to body water apparently occurred between 7 and 32 hr following injections of [6-3H} and [3-3H]glucose.Resynthesis of glucose from blood bicarbonate was equivalent to approximately 2% of the irreversible loss of glucose carbon, whereas resynthesis of carbonbound hydrogen of plasma glucose from body water was negligible, although about 91 % of this hydrogen was apparently derived from body water.It was suggested that 20-30% of the intermediates of glucose metabolism were utilized in synthetic reactions and that [2-3H]glucose with [U-14C]glucose was the most useful mixture of labelled glucoses for studies of glucose metabolism, particularly for estimating the extent of glucose resynthesis.

show abstract

“…EGP under basal conditions has been estimated by tracer techniques and by transhepatic catheterization studies (4,5,(8)(9)(10)(11)(12)(13)(39)(40)(41). Studies on the effect of insulin on glucose production have been complicated (a) by hypoglycemia and release of counterregulatory hormones when exogenous insulin has been administered or (b) by hyperglycemia when glucose has been administered as a stimulus to endogenous insulin release.…”

Section: Discussionmentioning

confidence: 99%

Insulin Control of Glucose Metabolism in Man

Insel¹,

Liljenquist²,

Tobin³

et al. 1975

J. Clin. Invest.

231

107

View full text Add to dashboard Cite

A B S T R A C T Analyses of the control of glucose metabolism by insulin have been hampered by changes in blood glucose concentration induced by insulin administration with resultant activation of hypoglycemic counterregulatory mechanisms. To eliminate such mechanisms, we have employed the glucose clamp technique which allows maintenance of fasting blood glucose concentration during and after the administration of insulin. Analyses of six studies performed in young healthy men in the postabsorptive state utilizing the concurrent administration of [1'C] During the glucose clamp experiments plasma insulin levels reached a plateau of 95±8 /U/ml. Over the entire range of insulin levels studied, glucose losses were best correlated with levels of insulin in a slowly equilibrating insulin compartment of a three-compartment insulin model. A proportional control by this compartment on glucose utilization was adequate to satisfy the observed data. Insulin also rapidly decreased the endogenous glucose production to 33% of its basal level (0.58 mg/ kg per min), this suppression being maintained for at least 40 min after exogenous insulin infusion was terminated and after plasma insulin concentrations had returned to basal levels.The change in glucose utilization per unit change in insulin in the slowly equilibrating insulin compartment is proposed as a new measure for insulin sensitivity. This defines insulin effects more precisely than previously used measures, such as plasma glucose/plasma insulin concentration ratios.Glucose clamp studies and the modeling of the coupled kinetics of glucose and insulin offers a new and potentially valuable tool to the study of altered states of carbohydrate metabolism.

show abstract

Effects of Insulin on Blood Glucose Entry and Removal Rates in Man

Cited by 12 publications

References 3 publications

Measurement of insulin sensitivity indices using ¹³C‐glucose and gas chromatography/combustion/isotope ratio mass spectrometry

Measurement of insulin sensitivity indices using ¹³C‐glucose and gas chromatography/combustion/isotope ratio mass spectrometry

Estimation of the Total Entry Rate and Resynthesis of Glucose in Sheep Using Glucoses Uniformly Labelled With 14C and Variously Labelled With 3H

Insulin Control of Glucose Metabolism in Man

Contact Info

Product

Resources

About

Effects of Insulin on Blood Glucose Entry and Removal Rates in Man

Cited by 12 publications

References 3 publications

Measurement of insulin sensitivity indices using 13C‐glucose and gas chromatography/combustion/isotope ratio mass spectrometry

Measurement of insulin sensitivity indices using 13C‐glucose and gas chromatography/combustion/isotope ratio mass spectrometry

Estimation of the Total Entry Rate and Resynthesis of Glucose in Sheep Using Glucoses Uniformly Labelled With 14C and Variously Labelled With 3H

Insulin Control of Glucose Metabolism in Man

Contact Info

Product

Resources

About

Measurement of insulin sensitivity indices using ¹³C‐glucose and gas chromatography/combustion/isotope ratio mass spectrometry

Measurement of insulin sensitivity indices using ¹³C‐glucose and gas chromatography/combustion/isotope ratio mass spectrometry