To determine the efficacy of coenzyme Q10 (CoQ10) and alpha-lipoic acid (⍺-LA), either alone or in combination, to protect the contractile responses of the rabbit urinary bladder from damage caused by repetitive stimulation in the presence or absence of in vitro ischemia.

Four groups of New Zealand white rabbits (4 per group) were treated with vehicle (group 1), CoQ10 (group 2), ⍺-LA (group 3), or CoQ10 plus ⍺-LA (group 4) for 2 weeks. At the end of the treatment period, eight longitudinal strips from each rabbit bladder body were placed in oxygenated Tyrode's solution with glucose (normal physiologic medium). The strips were stimulated by field stimulation, carbachol, and KCl, and the responses were recorded. One half of the strips were switched for 1 hour to Tyrode's solution with no glucose equilibrated with nitrogen (ischemia medium). Simultaneously, all strips were subjected to 1 h of repetitive field stimulation followed by 1 hour of recovery in normal physiologic medium, and the responses to all stimuli were recorded again.

CoQ10 showed no protective effect. ⍺-LA resulted in increased contractile responses of the control bladder and showed a moderate protective effect for all forms of stimulation. The combination, however, showed a significantly greater increase in the contraction of the control bladder and a greater protective effect than ⍺-LA alone.

The combination of ⍺-LA and CoQ10 treatment enhanced the contractile response in normal medium and diminished the contractile dysfunction induced by repetitive field stimulation and ischemia.