TLR4 and myocardial infarction: A recent study exposed animals to either LPS challenge (septic shock model) or to coronary artery ligation (myocardial ischemia (MI) model) and found that TLR4-deficient mice challenged with LPS or MI displayed reduced cardiac function, increased myocardial levels of IL-1β and TNF-α, and the upregulation of mRNA encoding TLR4 prior to myocardial leukocyte infiltration [21].