Muscle blood flow in diabetes mellitus: Evidence of abnormality after exercise

OBJECTIVE - To determine whether muscle blood flow before and after exercise is abnormal in patients with diabetes mellitus. RESEARCH DESIGN AND METHODS - Muscle blood flow (MBF) was measured with the ¹³³Xe clearance technique in 15 nondiabetic subjects, 10 patients with insulin-dependent diabetes mellitus (IDDM), and 11 patients with non-insulin-dependent diabetes (NIDDM) at rest and after exercise. None of the patients had neuropathy. RESULTS - The median resting MBF was similar in all three groups. The median postexercise MBF was significantly greater in nondiabetic subjects (40.1 ml · min^-1 · 100 g^-1 of tissue) than in patients with IDDM (25.7 ml · min^-1 · 100 g^-1 of tissue; P < 0.01) or NIDDM (14 ml · min^-1 · 100 g^-1 of tissue; P < 0.01). The difference between IDDM and NIDDM was not significant. CONCLUSIONS - Diabetic patients have abnormalities of MBF in response to exercise. This abnormality occurs in the absence of clinical diabetic neuropathy.