Macrophage stimulation reduces the cholesterol levels of stressed and unstressed rats

Male, Sprague-Dawley rats were either treated with zymosan, a nonspecific macrophage stimulator, or saline vehicle. Half of each group were then subjected to a stress procedure, the other half remained in their home cage. Results indicate that zymosan-treated animals had lower levels of total, low-density/very-low-density, and high-density lipoprotein than vehicle controls. Stressed animals had higher levels of the cholesterol parameters than did home cage controls. Manipulation of macrophage levels may be a prophylactic manipulation to combat stress-induced increases in cholesterol.