Syrian Golden hamster - A model forExamining Metabolic Effects of Volitional Training.

Abstract

1747 The Syrian Golden hamster is commonly used as a model of dietary induced insulin resistance. Fat metabolism in hamsters closely resembles that in humans and this animal is known to exercise voluntarily. PURPOSE: To explore the metabolic effects of volitional training on young, healthy Syrian hamsters. METHODS: Male, 24- day old, hamsters with initial weight of 46.6 ± 0.83g (mean ± SEM), were randomly divided into sedentary (n = 8) and trained (n = 8) groups. The training group had 24-hour access to running wheels over 4 weeks of study. Food consumption, body weight and running distance were recorded daily and blood glucose was measured once per week. Non-fasted animals were euthanized by decapitation under CO2 anaesthesia and blood and tissues were collected for analysis. Plasma leptin, insulin, GLP-1, glucagon and amylin concentrations were measured in 10ul of serum using a Rat/Mouse Endocrine Panel (Linco Research, Inc.). RESULTS: The distance ran increased during the training period from 12.8 ± 1.11km/day at week 1 to 20.3 ± 0.82km/day at week 4. By the second week, food consumption was significantly higher (p<0.01) in trained (9.6 ± 0.2g/day) than in sedentary (6.48 ± 0.13g/day) animals. Although both groups gained weight, there was no difference in body mass between groups at any time point. Right visceral fat pad was larger (p<0.001) in sedentary (0.72 ± 0.04g) than in trained (0.24 ± 0.02g) animals. There was no difference in the blood glucose over the duration of the study between the trained and sedentary controls (4.6 ± 0.08mM/L vs 4.8 ± 0.1mM/L respectively). Leptin levels in sedentary hamsters were higher (p<0.05) than in trained hamsters (92.2 ± 15.7pM vs 35.5 ± 6.17pM, respectively). No significant difference was seen between the trained and sedentary animals in plasma insulin (284 ± 50.6pM vs 291.6 ± 49.7pM) nor GLP-1 (14.57 ± 3.9pM vs 10.93 ± 1.4pM) levels. Plasma glucagon and amylin were not detectible in sufficient animals to allow for comparison between groups. CONCLUSION: Our observations reveal that the extremely high volume of exercise exhibited by the animals, as well as their metabolic profile, may make this animal model particularly useful for the study of physiological effects of heavy endurance type training on metabolism.