TY - JOUR
T1 - Effects of the rate of insulin infusion during isoglycemic, hyperinsulinemic clamp procedures on measures of insulin action in healthy, mature thoroughbred mares
AU - Urschel, K. L.
AU - Escobar, J.
AU - McCutcheon, L. J.
AU - Geor, R. J.
N1 - Copyright:
Copyright 2014 Elsevier B.V., All rights reserved.
PY - 2014/4
Y1 - 2014/4
N2 - The objective of this study was to determine whether the rate of insulin infusion during isoglycemic hyperinsulinemic clamp procedures affected measures of insulin action, including glucose disposal and plasma non-esterified fatty acid, endothelin-1, and nitric oxide concentrations, in mature, healthy horses. Eight thoroughbred mares were studied during a 2-h hyperinsulinemic clamp procedure, conducted at each of 4 rates of insulin infusion: 0 (CON), 1.2 (LOWINS), 3 (MEDINS), and 6 (HIGHINS) mU·kg-1·min-1. The infusion rate of a dextrose solution was adjusted throughout the clamp procedures to maintain blood glucose levels within 10% of baseline glucose concentrations. Plasma insulin concentrations were measured throughout the clamp procedures, and used with the rate of glucose infusion to calculate the plasma insulin concentration-to-rate of glucose infusion ratio, a measure of insulin action on glucose disposal. The rate of glucose infusion increased with rate of insulin infusion (P < 0.05). The plasma insulin concentration-to-rate of glucose infusion ratio was highest for the LOWINS treatment (P < 0.05) and decreased by 62% (P < 0.05) and 84% (P < 0.05) for the MEDINS and HIGHINS treatments, respectively. Although plasma non-esterified fatty acid concentrations were lower than baseline by t = 30 min of the clamp procedures in the LOWINS, MEDINS, and HIGHINS treatments (P < 0.05), the decline was similar for all 3 rates of insulin infusion. Jugular vein plasma nitric oxide and endothelin-1 concentrations were not affected by insulin infusion rate (P > 0.05). The data indicate that it is important to standardize insulin infusion rate if data are to be compared between hyperinsulinemic clamp studies.
AB - The objective of this study was to determine whether the rate of insulin infusion during isoglycemic hyperinsulinemic clamp procedures affected measures of insulin action, including glucose disposal and plasma non-esterified fatty acid, endothelin-1, and nitric oxide concentrations, in mature, healthy horses. Eight thoroughbred mares were studied during a 2-h hyperinsulinemic clamp procedure, conducted at each of 4 rates of insulin infusion: 0 (CON), 1.2 (LOWINS), 3 (MEDINS), and 6 (HIGHINS) mU·kg-1·min-1. The infusion rate of a dextrose solution was adjusted throughout the clamp procedures to maintain blood glucose levels within 10% of baseline glucose concentrations. Plasma insulin concentrations were measured throughout the clamp procedures, and used with the rate of glucose infusion to calculate the plasma insulin concentration-to-rate of glucose infusion ratio, a measure of insulin action on glucose disposal. The rate of glucose infusion increased with rate of insulin infusion (P < 0.05). The plasma insulin concentration-to-rate of glucose infusion ratio was highest for the LOWINS treatment (P < 0.05) and decreased by 62% (P < 0.05) and 84% (P < 0.05) for the MEDINS and HIGHINS treatments, respectively. Although plasma non-esterified fatty acid concentrations were lower than baseline by t = 30 min of the clamp procedures in the LOWINS, MEDINS, and HIGHINS treatments (P < 0.05), the decline was similar for all 3 rates of insulin infusion. Jugular vein plasma nitric oxide and endothelin-1 concentrations were not affected by insulin infusion rate (P > 0.05). The data indicate that it is important to standardize insulin infusion rate if data are to be compared between hyperinsulinemic clamp studies.
KW - Equine
KW - Hyperinsulinemia
KW - Hyperinsulinemic clamp
KW - Insulin resistance
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U2 - 10.1016/j.domaniend.2013.11.003
DO - 10.1016/j.domaniend.2013.11.003
M3 - Article
C2 - 24315754
AN - SCOPUS:84897590284
SN - 0739-7240
VL - 47
SP - 83
EP - 91
JO - Domestic Animal Endocrinology
JF - Domestic Animal Endocrinology
IS - 1
ER -