Abstract 284: Testosterone Replacement Attenuates Hyperplasia Development in an Androgen Deficient Model of Vascular Injury Independent of Matrix Metalloproteinase Regulation

Objectives: Clinical and epidemiological studies have shown low testosterone (TST) is associated with increased risk of vascular disease, yet the molecular mechanisms remain unclear. Matrix metalloproteinases (MMPs) are implicated in dysfunctional remodeling. Our group has previously demonstrated an inverse relationship between TST levels and MMP activity in vitro. We have also demonstrated androgen deficiency (AD)-modulated inflammatory signaling does not influence systemic MMPs in vivo. Here we investigated the role of AD and TST replacement in MMP-modulated remodeling in response to injury. Methods: Sub-physiological and physiological TST replacement was administered via implanted pellets in aged orchiectomized rats (0.5-5mg, Table 1). Serum TST was determined by ELISA. At 14d TST replacement rats underwent balloon angioplasty of the left common carotid. Young intact (YI), aged intact (AI), and orchiectomized placebo (Plac) animals served as controls. Carotids were collected 14d post-injury for intima:...