Acetaminophen glucuronidation accurately reflects gluconeogenesis
in fasted dogs.
Schwenk, W. Frederick, Jane C. Kahl.
Department of Pediatrics and Endocrine Research Unit, Mayo Clinic,
Rochester, Minnesota 55905
APStracts 3:0094E, 1996.
To assess whether acetaminophen glucuronide accurately reflects uridyl
diphosphate-glucose (UDP-glucose) derived from gluconeogenesis during
fasting, three mongrel dogs received infusions of [U-14C]lactate, [1
-13C]galactose and [6-3H]glucose (after fasting overnight or for 2 1/2
days). Three hours after initiation of the isotopes, acetaminophen
was given and the urinary acetaminophen glucuronide isolated. The
mean plasma [14C]glucose specific activity (SA) was similar to the
mean urinary acetaminophen glucuronide SA both after fasting
overnight (299 +/- 19 vs 296 +/- 14 dpm/_mol, respectively) and after
2 1/2 days of fasting (511 +/- 8 vs 562 +/- 32 dpm/_mol,
respectively). Mean plasma glucose flux calculated using [6
-3H]glucose decreased (p < 0.05) with two additional days of fasting
(18.7 +/- 1.2 vs 13.6 +/- 0.6 _mol/_kg-1_min-1), as did intrahepatic
(p < 0.05) UDP-glucose flux measured using [1-13C]galactose (8.6 +/-
0.7 vs 5.5 +/- 0.3 _mol_kg-1_min-1). We conclude that in fasted dogs,
plasma glucose and UDP-glucose as sampled by acetaminophen equally
reflect gluconeogenesis and appear to come from the same pool of
glucose-6-phosphate. In addition, cycling of glucose moieties through
UDP-glucose and glycogen decreases with an increased period of
fasting.
Received 17 November 1995; accepted in final form 23 April 1996.
APS Manuscript Number E547-5.
Article publication pending Am. J. Physiol. (Endocrinol. Metab.).
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 8 May 96