The relationship between plasma high density lipoprotein cholesterol levels and cholesteryl ester transfer protein activity in six species of healthy experimental animals

Plasma high-density lipoprotein cholesterol (HDL-C) concentrations are regulated by plasma cholesteryl ester transfer protein (CETP) in humans, The aim of this study was to ascertain the relationship between plasma HDL-C and plasma CETP activities in mouse, rat, dog, hamster, rabbit and monkey. In this study the plasma HDL-C levels were highest in dogs and lowest in rabbits among the sir; species. Plasma CETP activities were higher in hamsters, rabbits and monkeys compared to mice, rats and dogs. The present study shows that there are species differences in HDL-C and CETP activity in sis species of healthy experimental animals, with the sis species being separated into two types, The first type showed a high HDL-C/TC ratio with low or absent CETP activity; and included mouse, rat and dog, whereas the second type showed a low HDL-C/TC ratio and high CETP activity, and included hamster, rabbit and monkey. The present study also shows that there is a strong relationship between plasma HDL-C levels and CETP activity in high CETP activity animals and that the relationship between the HDL-C/TC ratio and CETP activity is an important factor in all animals, regardless of CETP activity level.