First Author | Zhang Y | Year | 2005 |
Journal | J Clin Invest | Volume | 115 |
Issue | 10 | Pages | 2870-4 |
PubMed ID | 16200214 | Mgi Jnum | J:101524 |
Mgi Id | MGI:3604227 | Doi | 10.1172/JCI25327 |
Citation | Zhang Y, et al. (2005) Hepatic expression of scavenger receptor class B type I (SR-BI) is a positive regulator of macrophage reverse cholesterol transport in vivo. J Clin Invest 115(10):2870-4 |
abstractText | Hepatic expression of the scavenger receptor class B type I (SR-BI) promotes selective uptake of HDL cholesterol by the liver and is believed to play a role in the process of reverse cholesterol transport (RCT). We hypothesized that hepatic SR-BI expression is a regulator of the rate of integrated macrophage-to-feces RCT and used an in vivo model to test this hypothesis. Cholesterol-loaded and [3H]cholesterol-labeled J774 macrophages were injected intraperitoneally into mice, after which the appearance of the [3H]cholesterol in the plasma, liver, and feces over 48 hours was quantitated. Mice overexpressing SR-BI in the liver had significantly reduced [3H]cholesterol in the plasma but markedly increased [3H] tracer excretion in the feces over 48 hours. Conversely, mice deficient in SR-BI had significantly increased [3H]cholesterol in the plasma but markedly reduced [3H] tracer excretion in the feces over 48 hours. These studies demonstrate that hepatic SR-BI expression, despite its inverse effects on steady-state plasma HDL cholesterol concentrations, is an important positive regulator of the rate of macrophage RCT. |