Use of the hyperinsulinemic euglycemic clamp to assess insulin sensitivity in guinea pigs: dose response, partitioned glucose metabolism, and species comparisons

作者:Horton Dane M; Saint David A; Owens Julie A; Gatford Kathryn L; Kind Karen L
来源:American Journal of Physiology - Regulatory, Integrative and Comparative Physiology, 2017, 313(1): R19-R28.
DOI:10.1152/ajpregu.00028.2017

摘要

The guinea pig is an alternate small animal model for the study of metabolism, including insulin sensitivity. However, only one study to date has reported the use of the hyperinsulinemic euglycemic clamp in anesthetized animals in this species, and the dose response has not been reported. We therefore characterized the doseresponse curve for whole body glucose uptake using recombinant human insulin in the adult guinea pig. Interspecies comparisons with published data showed species differences in maximal whole body responses (guinea pig approximate to human < rat < mouse) and the insulin concentrations at which half-maximal insulin responses occurred (guinea pig > human approximate to rat > mouse). In subsequent studies, we used concomitant D-[3-H-3] glucose infusion to characterize insulin sensitivities of whole body glucose uptake, utilization, production, storage, and glycolysis in young adult guinea pigs at human insulin doses that produced approximately half-maximal (7.5 mU center dot min(-1) center dot kg(-1)) and near-maximal whole body responses (30 mU center dot min(-1) center dot kg(-1)). Although human insulin infusion increased rates of glucose utilization (up to 68%) and storage and, at high concentrations, increased rates of glycolysis in females, glucose production was only partially suppressed (similar to 23%), even at high insulin doses. Fasting glucose, metabolic clearance of insulin, and rates of glucose utilization, storage, and production during insulin stimulation were higher in female than in male guinea pigs (P < 0.05), but insulin sensitivity of these and whole body glucose uptake did not differ between sexes. This study establishes a method for measuring partitioned glucose metabolism in chronically catheterized conscious guinea pigs, allowing studies of regulation of insulin sensitivity in this species.

  • 出版日期2017-7