Thrombospondin-4 knockout in hypertension protects small artery endothelial function but induces aortic aneurysms.
Thrombospondin-4 (TSP-4) is a multidomain calcium-binding protein that has both intracellular and extracellular functions. As an extracellular matrix protein it is involved in remodeling processes. Previous work showed that in the cardiovascular system, TSP-4 expression is induced in the heart in response to experimental pressure overload and infarction injury. Intracellularly, it mediates the end