Exercise activates vagal induction of dopamine and attenuates systemic inflammation.

•A single session of swimming attenuates systemic inflammation without affecting glycemia in endotoxemia.•A single session of moderate swimming attenuates kidney dysfunction in endotoxemia.•Moderate aerobic exercise attenuated serum TNF levels by inhibiting its production in the spleen through subdiaphragmatic vagus nerve.•Training exercise for 7 days can improve mice survival in experimental endotoxemia.•Serum from mice with exercise attenuated TNF production in primary culture of splenocytes from naïve mice without exercise.•Dopamine and dopaminergic agonist type-1, fenoldopam, inhibited TNF production in splenocytes.•Dopaminergic antagonist type-1, butaclamol, attenuated exercise control of serum TNF levels in endotoxemia.