The role of nitric oxide in endotoxin-induced cardiodepression.

Objective: To determine the participation of inducible nitric oxide synthase (iNOS) in cardiodepressive phenomena during late preconditioning caused by subtoxic doses of lipopolysaccharide (LPS).

Methods: Spontaneously beating hearts isolated from male Wistar rats (350 g to 400 g), intact or preconditioned with LPS (0.25 mg/kg given intraperitoneally 18 h before heart excision), were used to measure contractile performance during 30 min of ischemia and 40 min of reperfusion in the Langendorff mode.