Figure 4.

Comparison of percentage capillary area among respiratory-deficient and more normal fibres within skeletal muscle of individual patients with mitochondrial myopathy. (A) In each patient, respiratory-deficient (cytochrome oxidase-negative or ragged-red) fibres contain significantly higher (P < 0.001) levels of capillaries compared with more normal fibres. (B) Percentage capillary area increases in direct proportion to the percentage of cytochrome oxidase-negative fibres in the seven patients whose mutation affects cytochrome oxidase activity (r² = 0.90; P < 0.01). COX = cytochrome oxidase. ▴ = Patient 1; • = Patient 2; ☆ = Patient 3; ♦ = Patient 4; △ = Patient 5; ▪ = Patient 6; ▽ = Patient 7; □ = Patient 8; and ◊ = Patient 9.