MUSCLE UBIQUINONE IN MALE EFFORT ANGINA PATIENTS

Seven (7) males with effort angina and listed for coronary by-pass sur gery had muscle biopsies taken from their vastus lateralis muscle for determination of muscle fiber types (%ST), ubiquinone (vitamin Q, UQ), oxidative and fermentative enzyme activities. Graded cycle ergometer exercise to determine intensities corresponding to onset of blood lact ate accumulation set to 2.0 mmol x l(-1) (W-OBLA) and symptom limited exercise ('maximal', W-SL) were also undertaken. W-OBLA was positively related to %ST (r = 0.92, p < 0.001). %ST was on the other hand inver sely related to UQ (r = -0.82, p < 0.05), the heart specific LD subuni t LD-H (r = -0.96, p < 0.001), the isozyme LD(3) as the fraction of LD (%LD(3)) (r = -0.93, p < 0.01), and the CK isozyme CKMB as the fracti on of CK (%CKMB) (r = -0.88, p < 0.05). It was suggested that muscle U Q depletion in the patients was related to molecular oxygen and free o xygen radical formation. The lack of antioxidants then caused a radica l trauma specifically to the ST fiber and their mitochondria. This cou ld be a cause and-effect explanation for the selective ST fiber down-r egulation in effort angina and heart failure in general.