Exercise benefits cardiovascular health in hyperlipidemia rats correlating with changes of the cardiac vagus nerve.

The role of exercise training on hemodynamic parameters, blood lipid profiles, inflammatory cytokines, cholinesterase-positive nerves and muscarinic cholinergic (M(2)) receptors expression in the heart was investigated in Sprague-Dawley male rats with hyperlipidemia (HL). The rats were subjected to a high-fat diet and exercise training for 8 weeks, and then the hemodynamic parameters, the profiles of blood lipid and inflammatory cytokines, and the expression of cholinesterase-positive nerves and M(2) receptors were measured. HL rats displayed cardiac dysfunction, dysregulation of inflammatory cytokines, and decreased cholinesterase-positive nerves and M(2) receptors expression. The combination of hyperlipidemia with exercise training (AT) restored the profiles of blood lipids and the levels of inflammatory cytokines. In addition, AT and HL + AT improved cardiac function with increasing cholinesterase-positive nerves and M(2) receptors expression. Overall, these data show that the increased expression of cholinesterase-positive nerves and M(2) receptors in the heart is partially responsible for the benefits of exercise training on cardiac function in hyperlipidemia rats.