Dichloroacetate lessens the effects of static exercise on sympathetic nerve responses.
S. Ettinger, K. Gray, S. Whisler, and L. Sinoway are only a few of the authors.
Division of Cardiology, Milton S. Hershey Medical Center, Pennsylvania State University, Hershey, 17033.
It is believed that lactic acid stimulates muscular metaboreceptors. The purpose of the current investigation was to ascertain if muscle sympathetic nerve activity (MSNA) during static forearm exercise would be reduced if lactic acid generation was inhibited by dichloroacetate (DCA). Pyruvate dehydrogenase levels are raised by DCA. Thus, less lactic acid is created for a given amount of pyruvate produced. Seven participants engaged in a static forearm exercise at 20% of their maximum voluntary contraction until they became fatigued, at which point they experienced posthandgrip circulatory arrest (PHG-CA) (trial.1). After receiving DCA (35 mg/kg), subjects repeated the workout regimen (trial 2). Forearm venous lactate and MSNA showed a reduced increase. In comparison to trial 1, the MSNA value during PHG-CA in trial 2 was 51 +/- 11% lower (P less than 0.01). Seven control volunteers had two sessions of static forearm exercise with a saline infusion in between. Exercise-induced changes in lactate or MSNA were unaffected by this intervention. We come to the conclusion that DCA reduces the lactate responses to static exercise, which is connected to a reduced MSNA response.