This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. A Twelve-Week Randomized, Double-Blind, Placebo-controlled Pilot Study to assess the Effect of Monthly (q4wk) High-Dose Oral Cholecalciferol (100,000 IU Vitamin D3) on Vascular Function and Cardiovascular Risk Factors in Overweight, Hypertensive African-Americans with Hypovitaminosis D. Multicenters of RCMI Translational Research Network (RTRN) are involved. MSM is one of sites to enroll the participants.