PERITONEAL-MACROPHAGES FROM STROKE-PRONE SPONTANEOUSLY HYPERTENSIVE RATS ACCUMULATE MORE CHOLESTERYL ESTER THAN DO MACROPHAGES FROM WISTAR-KYOTO RATS

The intracellular cholesterol metabolism of peritoneal macrophages from stroke-prone spontaneously hypertensive rats (SHRSP) was compared to that of normotensive Wistar-Kyoto rats (WKY) in order to examine the role of macrophages in the development of arterial fat deposits in the SHRSP. Scavenger receptor activity and intracellular acyl CoA:cholesterol acyltransferase (ACAT) activity were significantly higher in macrophages from SHRSP compared to findings in WKY, in the presence of modified low-density lipoprotein (LDL), acetylated-LDL (Ac-LDL). Moreover, macrophages from the SHRSP accumulated more cholesteryl ester than seen in WKY in response to Ac-LDL. ACAT activity and cholesteryl ester accumulation were inhibited by specific ACAT inhibitor, HL-004, to a similar extent, in macrophages from WKY and SHRSP. These findings suggest the susceptibility of SHRSP to arterial fat deposits. (C) 1995 Academic Press, Inc.