Time course of capillary regression and an expression balance between vascular endothelial growth factor-A and thrombospondin-1 in the soleus muscle of hindlimb unloaded rats.

Depending on the HU period, VEGF-A and TSP-1 showed different expression patterns. In the early HU phase, TSP-1 may play an important role in capillary regression. However, when HU extends for a longer period, decreased VEGF-A, and/or increased oxidative stress may be more involved in capillary regression.