Effects of diabetes and of injury on muscle protein in the mouse, and their interaction.

The effects of a 20% dorsal scald injury and of different severities of streptozotocin diabetes on hindquarter muscle protein have been studied in the mouse. Ten days after scald injury muscle protein contents were generally unaffected, whereas moderate diabetes (200 mg streptozotocin/kg body weight; plasma glucose concentrations 17--46 mmol/1; normal 11 mmol/l) led to net loss of muscle protein. Production of scald injury in the moderately diabetic mouse caused significant additional loss of muscle protein, especially from the extensor digitorum longus Milder diabetes (maximum plasma glucose concentration 15 mmol/l) did not lead to loss of muscle protein. However, scald injury in the mildly diabetic mouse caused significant loss of protein from all muscles studied. The effects of diabetes and of injury on loss of muscle protein were at least additive and in some muscles probably synergistic.