Muscle enzyme activity and insulin sensitivity in type 1 (insulin-dependent) XXXX mellitus.

@entity1 @entity4051 @entity6 @entity413 @entity2388
The mechanisms of insulin insensitivity in @entity6 are poorly understood. We have therefore assessed the relationship between @entity413 disposal during a euglycaemic clamp, muscle glycogen formation, and the activities of insulin regulated enzymes within skeletal muscle in five Type 1 (insulin-dependent) @entity6 @entity1 , both on conventional injection therapy ( @entity4051 11.0 +/- 1.0 (SD) %) and after 6 weeks continuous subcutaneous insulin infusion ( @entity4051 7.6 +/- 1.4%, p less than 0.01). On both regimens, overnight euglycaemia before the clamp was maintained with an intravenous insulin infusion. The increase in clamp @entity413 requirements (insulin 0.1 U X kg-1 X h-1) between injection therapy and continuous subcutaneous insulin infusion was significant (6.2 +/- 0.9 (SE) to 7.0 +/- 0.9 mg X kg-1 X min-1, p less than 0.05), but small compared to differences between subjects. @entity413 requirement remained lower than in control subjects (10.4 +/- 0.7 mg X kg-1 X min-1, p less than 0.05). The increase in muscle glycogen with the clamp was slightly higher on continuous subcutaneous insulin infusion (9.5 +/- 2.5 mg/g protein) than on injection therapy (8.5 +/- 2.4 mg/g, p less than 0.05), but less than in control subjects (17.9 +/- 2.1 mg/g, p less than 0.05). The expressed activity of glycogen synthase and @entity2388 dehydrogenase increased significantly between fasting and the end of the clamps in the @entity1 (p less than 0.001 and less than 0.005), but was not significantly different between the two treatment regimens. Expressed glycogen synthase activity at the end of the clamp was lower on both treatments than in control subjects (p less than 0.05). Both enzyme activities were, however, highly correlated with @entity413 requirement between @entity1 , (r = 0.89-0.94, p less than 0.05-0.02), and glycogen synthase was similarly correlated in the control subjects (r = 0.84, p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)
