Effect of isotope infusion and sampling sites on glucose kinetics during a euglycemic clamp

Abstract

The importance of the location of isotope infusion and blood sampling on calculating glucose kinetics was studied in five mongrel dogs in the basal state and when glucose turnover was increased during a hyperinsulinemic euglycemic clamp. [U-14C]glucose was infused into the pulmonary artery, unlabeled glucose was infused into a femoral vein to maintain euglycemia, and blood was sampled from the right atrium (AV mode) and the femoral artery (VA mode). In the basal state there was no difference between the AV or VA mode in plateau specific activity; hence, the calculated rate of appearance of glucose was the same with either mode. During the euglycemic clamp procedure, plateau specific activity of the AV mode was significantly lower than that of the VA mode (P less than 0.05). The rate of appearance of glucose calculated from the VA mode was almost identical to the rate of infusion of unlabeled glucose (13.0 +/- 1.4 vs. 12.6 +/- 1.4 mg.kg-1.min-1, respectively), but the rate of appearance of glucose calculated from the AV mode was 12% greater. This study demonstrates that the calculation of glucose kinetics is sensitive to differences in sampling site when the turnover rate is high relative to the mass flow rate (cardiac output times substrate concentration).

Effectiveness of milk whey protein‐based ready‐to‐use therapeutic food in treatment of severe acute malnutrition in Malawian under‐5 children: a randomised, double‐blind, controlled non‐inferiority clinical trial

“…Both RUTFs provided daily amount of cysteine and methionine higher than the 391.2 and 496.5 μmol kg −1 day −1 associated with rapid restoration of glutathione homeostasis (Jahoor et al . ; Solak & Akin ). However, children taking P‐RUTF had a cysteine intake of 385 μmol kg −1 day −1 lower than that of those taking WPC34 which was 825 μmol kg −1 day −1 .…”

“…Our study was not designed to assess the effect of incidence of morbidity, time to resolution of oedema or lean mass deposition, but theoretically, the extra intake of cysteine taken by children of the WPC34 arm did probably lead to an improvement of these outcomes especially in children admitted with oedematous malnutrition as they have a very high cysteine requirement (Jahoor et al . ; Marshall ; Badaloo et al . ).…”

Contributions of white and brown adipose tissues and skeletal muscles to acute cold‐induced metabolic responses in healthy men

“…The practice of venous stable isotope infusion and arterialized venous blood sampling has been identified as the accepted infusion and sampling method when measuring glucose or NEFA kinetics (Jahoor et al . ; Wolfe & Chinkes, ). However, cold‐induced vasoconstriction of the hand and forearm preclude the possibility of applying such a method in the current study.…”

“…It is important to note that blood sampling and infusion sites may have effects on the measurement of glucose and fatty acid kinetics (Jensen, 1991;Wolfe & Chinkes, 2005). The practice of venous stable isotope infusion and arterialized venous blood sampling has been identified as the accepted infusion and sampling method when measuring glucose or NEFA kinetics (Jahoor et al 1988;Wolfe & Chinkes, 2005). However, cold-induced vasoconstriction of the hand and forearm preclude the possibility of applying such a method in the current study.…”