Which substance increases oxygen radical-induced myocardial reperfusion injury?

The correct choice is sugars, as they play a significant role in the context of reperfusion injury, particularly in the production of free radicals. During myocardial reperfusion—which is the restoration of blood flow to heart tissue that has been ischemic—oxygens radicals can be generated. This oxidative stress can contribute to cellular damage and exacerbate myocardial injury.

Sugars, especially when in high concentrations, can influence metabolic states and lead to an increased production of free radicals. This is particularly relevant in the context of hyperglycemia or when elevated blood glucose levels are present during the reperfusion phase. The metabolic pathways involved in sugar metabolism can overload the heart tissue with free radicals, thereby increasing myocardial injury.

In contrast, heparin primarily serves as an anticoagulant, and while it may influence blood flow dynamics, it does not directly contribute to increased oxidative stress related to reperfusion injury. Platelets are involved in clotting and can play a role in thrombotic events, but their primary function does not increase oxygen radical production. Aprotinin is a serine protease inhibitor that has been used to reduce inflammation and minimize reperfusion injury but does not promote radical formation. Thus, sugars are uniquely implicated in enhancing oxidative stress during myocardial reperfusion injury