| Objective To investigate the changes of glucose metabolism, plasmaresistin and adiponectin levels in the insulin-resistant rats induced byhigh-fat diet. Methods Male SD rats were randomly divided into normal-chowdiet (NC) group and high-fat diet (HF) group and fed with correspondingfood for 8 weeks. Insulin sensitivity and glucose metabolism wereevaluated by extended hyperinsulinemic-euglycemic clamp technique. Andplasma resistin and adiponectin levels in basal and steady state were alsodetected. Results (1)In basal state, the plasma levels of free fatty acids (FFA)were significantly increased in HF group (P<0.05). There was no differencein plasma insulin (INS) levels between the two groups, even with a mildincrement in HF group. (2)In steady state, plasma INS levels in HF groupwere significantly higher than that in NC group (P<0.01),even with thesame INS infusion rate in both groups. And plasma FFA levels were bothsignificantly suppressed, but they were still higher in HF group comparedwith NC group (P<0.01). (3)The GIR in HF group was reduced by ～37%compared with NC group (P<0.01), and insulin-stimulated glucose disposal(GRd ) was also blunted. Insulin-mediated suppression of HGP wasimpaired in HF group. (4)The plasma resistin and adiponectin levels inboth groups were similar in basal state. But at the end of the clamp, theplasma resistin levels in HF group were not decreased as that in NC group.And plasma adiponectin levels were both decreased finally. Conclusion High-fat diet induced the insulin resistance in rats andaccompanied with reduced GRd,as well as impaired Insulin-mediatedsuppression of HGP and lipolysis. The IR in HF group might be associatedwith the elevated plasma FFA levels and higher steady-state plasma resistinlevels. Plasma adiponectin unlikely played an important role in thedevelopment of IR in this model. And insulin could downregulate theplasma resistin and adiponectin levels.
|
PDF Full Text Request