EFFECT OF INTRALIPID INFUSION ON SERUM HIGH-DENSITY AND LOW-DENSITY-LIPOPROTEIN CHOLESTEROL, LECITHIN CHOLESTEROL ACYLTRANSFERASE, AND LIPOPROTEIN-LIPASE IN TUMOR-BEARING RATS

We compared the effects of 0.45% normal saline (NS), 5% Intralipid(R) (IL), and 16.7% glucose (Glu) infusions on total serum triglycerides a nd cholesterol, serum high-(HDL-c) and low-density lipoprotein cholest erol (LDL-c), and activity of serum lecithin: cholesterol acyltransfer ase (LCAT), and serum lipoprotein lipase (LPL) in rats implanted with a fibrosarcoma. In tumor-bearing rats given NS, a two-fold increase in total serum cholesterol, a four-fold increase in LDL-c, and a five-fo ld decrease in the HDL-c/LDL-c ratio were observed compared to tumor-f ree rats. In tumor-bearing rats administered IL, a two-fold increase i n total serum triglyceride and cholesterol, a three-fold increase in H DL-c and HDL-c/LDL-c ratio, and a two-fold increase in LPL activity we re observed compared to tumor-bearing rats administered NS. In tumor-b earing rats administered Glu, a two-fold decrease in total serum chole sterol, a two-fold decrease in HDL-c, and a three-fold decrease in LDL -c were observed compared to tumor-bearing rats administered NS. Tumor weights and LCAT activity did not differ significantly between treatm ent groups. Previous results have demonstrated that lipophilic compoun ds that interact with plasma lipoproteins have altered pharmacological effects when administered with IL. Therefore, this study suggests tha t IL infusions alter the HDL-c/LDL-c ratio and could affect the pharma cological behavior of anticancer compounds that predominantly distribu te into the LDL fraction upon entrance into the bloodstream.