Impaired adaptation of first phase insulin secretion in postmeno
pausal women with glucose intolerance.
Ahr[acute]en, Bo, and Giovanni Pacini.
Department of Medicine, Lund University, Malm[diaeresis]o, Sweden,
and Institute of Systems Science and Biomedical Engineering (LADSEB
-CNR), Padua, Italy
APStracts 4:0129E, 1997.
This study examined whether insulin secretion, insulin sensitivity,
glucose effectiveness and hepatic extraction of insulin are altered
in subjects with impaired glucose tolerance (IGT). The frequently
sampled intravenous glucose tolerance test was performed in
postmenopausal women (age 63 years, body mass index range 21.6-28.9
kg/m2) with IGT (n=10) or normal glucose tolerance (NGT; n=10).
Insulin sensitivity, SI, was significantly lower in IGT than in NGT
(p=0.030). In contrast, insulin secretion was not significantly
different between the two groups as determined by area under the
curve for insulin and C-peptide, acute insulin response to glucose
(AIRG), and glucose sensitivity of first phase, [stod]o1, or of
second phase, [stod]o2, insulin secretion. In NGT (r=-0.68, p=0.029)
but not in IGT (r=-0.05, n.s.), SI correlated negatively with
[stod]o1. The B cell "adaptation index" (SI times [stod]o1)
was lower in IGT than in NGT (83+/-25 vs 171+/-29 min-2/(mmol/l),
p=0.042). Also the B cell "disposition index" (SI times AIRG)
was lower in IGT (83+/-25 10-4 min-1) than in NGT (196+/-30 10-4 min
-1; p=0.011). In contrast, glucose effectiveness, SG, or hepatic
extraction of insulin was not different between IGT and NGT. We
conclude that postmenopausal women with IGT fail to adequately adapt
to lowered insulin sensitivity by increasing first phase insulin
secretion.
Received 13 March 1997; accepted in final form 6 June 1997.
APS Manuscript Number E111-7.
Article publication pending Am. J. Physiol. (Endocrinol. Metab.).
ISSN 1080-4757 Copyright 1997 The American Physiological Society.
Published in APStracts on 1 July 1997