Controversy exists concerning glucose utilization, insulin and the role of ATP in glucose uptake during hemorrhagic shock. To study this, Holtzman rats were bled while awake to a mean arterial pressure of 40 mm Hg for 2 hrs and sacrificed. Soleus muscles were quickly removed and incubated at 37° in Krebs HCO3 buffer containing 10 mM glucose ± insulin (0.1 U/ml). After 1 hr, muscles were homogenized in a TCA HCl mixture and analyzed enzymatically for ATP. Glucose uptake was measured by glucose disappearance from the medium. Values are means of 4 experiments ± S.E. in μmoles glucose/g/hr and μmoles ATP/g. There was no difference in basal glucose uptake in controls and animals in shock, even though ATP was lower with shock. Insulin stimulated glucose uptake in control muscle but had no effect on shock muscle. Thus, during shock there was no relationship between glucose uptake and ATP levels and muscles from rats in shock were not responsive to insulin. This lack of effect of insulin could be due to conformational changes in the muscle membrane.