The water extract of Jagamchotang protects the ischemia/reperfusion-induced cytotoxicity of rat neonatal myocardial cells via generation of nitric oxide.

Jagamchotang has been used for treatment of ischemic myocardial diseases in Chinese traditional medicine. However, little is known about the mechanism by which Jagamchotang rescues myocardial cells from ischemic damages. To elucidate the protective mechanisms, the effects of Jagamchotang on ischemia/reperfusion-induced cytotoxicity and generation of nitric oxide (NO) are investigated in primary neonatal myocardial cells. Ischemia/reperfusion itself induces severe myocardial cell death in vitro. However, treatment of the cells with Jagamchotang significantly reduces both ischemia/reperfusion-induced myocardial cell death and LDH release. In addition, pretreatment of Jagamchotang before reperfusion recovers the lose of beating rates after ischemia/reperfusion. For a while, the water extract of Jagamchotang stimulates myocardial cells in ischemic condition to produce nitric oxide (NO) in a dose dependent manner and it protects the damage of myocardial cells. Furthermore, the protective effects of the water extract of Jagamchotang is mimicked by treatment of sodium nitroprusside, an exogenous NO donor. NG-monomethyi-L-argine (NGMMA), a specific inhibitor of nitric oxide synthase (NOS), significantly blocks the protective effects of Jagamchotang on the cells after ischemia/reperfusion. Taken together, we suggest that the protective effects of Jagamchotang against ischemia/reperfusion-induced myocardial damages may be mediated by NO production during ischemic condition.