TY - JOUR
T1 - Dynamics of glucagon secretion in mice and rats revealed using a validated sandwich ELISA for small sample volumes.
AU - Albrechtsen, Nicolai Jacob Wewer
AU - Kuhre, Rune Ehrenreich
AU - Windeløv, Johanne Agerlin
AU - Ørgaard, Anne
AU - Deacon, Carolyn F.
AU - Kissow, Hannelouise
AU - Hartmann, Bolette
AU - Holst, Jens Juul
PY - 2016/8/1
Y1 - 2016/8/1
N2 - Glucagon is a metabolically important hormone, but many aspects of its physiology remain obscure, because glucagon secretion is difficult to measure in mice and rats due to methodological inadequacies. Here, we introduce and validate a low-volume, enzyme-linked immunosorbent glucagon assay according to current analytical guidelines, including tests of sensitivity, specificity, and accuracy, and compare it, using the Bland- Altman algorithm and size-exclusion chromatography, with three other widely cited assays. After demonstrating adequate performance of the assay, we measured glucagon secretion in response to intravenous glucose and arginine in anesthetized mice (isoflurane) and rats (Hypnorm/midazolam). Glucose caused a long-lasting suppression to very low values (1–2 pmol/l) within 2 min in both species. Arginine stimulated secretion 8- to 10-fold in both species, peaking at 1–2 min and returning to basal levels at 6 min (mice) and 12 min (rats). D-Mannitol (osmotic control) was without effect. Ketamine/xylazine anesthesia in mice strongly attenuated (P < 0.01) α-cell responses. Chromatography of pooled plasma samples confirmed the accuracy of the assay. In conclusion, dynamic analysis of glucagon secretion in rats and mice with the novel accurate sandwich enzyme-linked immunosorbent assay revealed extremely rapid and short-lived responses to arginine and rapid and profound suppression by glucose.
AB - Glucagon is a metabolically important hormone, but many aspects of its physiology remain obscure, because glucagon secretion is difficult to measure in mice and rats due to methodological inadequacies. Here, we introduce and validate a low-volume, enzyme-linked immunosorbent glucagon assay according to current analytical guidelines, including tests of sensitivity, specificity, and accuracy, and compare it, using the Bland- Altman algorithm and size-exclusion chromatography, with three other widely cited assays. After demonstrating adequate performance of the assay, we measured glucagon secretion in response to intravenous glucose and arginine in anesthetized mice (isoflurane) and rats (Hypnorm/midazolam). Glucose caused a long-lasting suppression to very low values (1–2 pmol/l) within 2 min in both species. Arginine stimulated secretion 8- to 10-fold in both species, peaking at 1–2 min and returning to basal levels at 6 min (mice) and 12 min (rats). D-Mannitol (osmotic control) was without effect. Ketamine/xylazine anesthesia in mice strongly attenuated (P < 0.01) α-cell responses. Chromatography of pooled plasma samples confirmed the accuracy of the assay. In conclusion, dynamic analysis of glucagon secretion in rats and mice with the novel accurate sandwich enzyme-linked immunosorbent assay revealed extremely rapid and short-lived responses to arginine and rapid and profound suppression by glucose.
U2 - 10.1152/ajpendo.00119.2016
DO - 10.1152/ajpendo.00119.2016
M3 - Journal article
C2 - 27245336
SN - 0193-1849
VL - 311
SP - E302-E309
JO - American Journal of Physiology: Endocrinology and Metabolism
JF - American Journal of Physiology: Endocrinology and Metabolism
IS - 2
ER -