ubiquinone-8 + NADH + H(+) <=> ubiquinol-8 + NAD(+)
ubiquinone-8 + nadh + h(+) <=> ubiquinol-8 + nad(+)
ubiquinone-8 + NADH + H(+) <=> ubiquinol-8 + NAD(+)
ubiquinone-8 + nadh + h(+) <=> ubiquinol-8 + nad(+)