Abstract
Background Sleeve gastrectomy (SG) procedure has been proved to improve insulin sensitivity
and sustain anti-diabetic effects. Our aim is to co-use several methods to measure
insulin sensitivity and investigate the effect of SG on hepatic and peripheral insulin
sensitivity at early and long-term stages of postoperation.
Methods Thirty 11-week-old male Goto-Kakizaki rats were divided into SG, sham-operated SG
(SOSG), and control groups. They were observed before operation and for 36 weeks of
postoperation. Insulin tolerance test (ITT) and homeostasis model of assessment for
insulin resistance index(HOMA-IR)were used to measure insulin resistance before operations
and at 2 and 36 weeks of postoperation; Pyruvate challenge test (PCT) was administrated
to assess the gluconeogenesis capability in order to reflect hepatic insulin sensitivity
before operation and at 2 and 36 weeks of postoperation; Hyperinsulinemic euglycemic
clamps (HIEC) was conducted before operation and at 2 and 36 weeks of postoperation
to calculate the endogenous hepatic glucose production (HGP) at the basal and steady-state
for evaluation of hepatic insulin sensitivity, and calculate the exogenous glucose
infusion rate (GIR) at the steady-state for evaluation of peripheral insulin sensitivity.
Results The data showed that compared with rats in the sham and control groups, rats in
SG group had 1) significantly lower AUCITT, HOMA-IR and AUC PCT values at 2 and 36 weeks of postoperation, 2) lower basal state HGP, but not steady-state
GIR at 2 weeks of postoperation, and 3) significantly different basal and steady-state
HGP and steady-state GIR at 36 weeks of postoperation. In addition, the basal and
steady-state HGP and the steady-state GIR were significantly different between rats
in SG group at 2 and 36 weeks of postoperation.
Conclusions This study explored insulin sensitivity of rats after SG by jointly using a variety
of techniques. The results showed that SG time-dependently improved the hepatic and
peripheral insulin sensitivity.
Key words
Sleeve gastrectomy - Insulin sensitivity - Goto-Kakizaki rats
