Heart muscle ubiquinone and plasma antioxidants following cardiac transplantation.

Nine patients who underwent heart transplantation (one female; average age 48 +/- 11, range 19-58 years) were followed in respect to contents of right-sided heart septum, blood and plasma ubiquinone (UQ), plasma alpha-tocopherol (alpha T), and plasma free cholesterol (FC). In contrast to healthy persons, substantial inter- and intraindividual variations were observed; individually low values were seen with rejection. Heart muscle UQ in well-treated patients averaged 0.33 +/- 0.08, range 0.06-0.58 micrograms mg-1 (0.38 +/- 0.09 mumol g-1 dry weight) and was not different from healthy individuals. Plasma UQ, alpha T; and FC averaged 0.63 +/- 0.33 micrograms ml-1 (P < 0.05 versus sedentary controls), 8.1 +/- 4.0 micrograms ml-1 (P < 0.01), and 0.52 +/- 0.23 mg ml-1 (P < 0.05). Corresponding molar values were 0.73 +/- 0.37 (UQ), 2.0 +/- 1.1 mumol l-1 (alpha T), and 1.42 +/- 0.54 mmol l-1 (FC). Blood and plasma UQ values were identical. A saturation like relationship was found between heart and blood UQ:blood contents below 0.7 micrograms ml-1 (0.8 mumol l-1) corresponded to markedly lowered heart contents. In four patients in whom blood samples were taken close to a fatal complication it averaged 0.42 micrograms ml-1 (0.49 mumol l-1, P < 0.01). When low heart muscle and blood ubiquinone were present, other variables such as left ventricle cardiac output or cycle ergometer performance was markedly impaired. Plasma UQ and alpha T covaried with a marker of the lipoidal deposit volume, plasma FC.(ABSTRACT TRUNCATED AT 250 WORDS)