Relationship between lipoproteins including HDL subfractions and the intravenous fat tolerance test.

There is a positive relationship between the HDL cholesterol concentration and the fractional removal rate k2 of intravenously administered Intralipid, the intravenous fat tolerance test (IVFTT). This relationship was analysed in 22 female and 20 male healthy normolipoproteinaemic volunteers with regard to HDL subfractions. A positive correlation between the IVFTT k2 value and HDL cholesterol (r = 0.40, P less than 0.05) was confirmed. The k2-HDL2 cholesterol relationship was strong and positive (r = 0.56, P less than 0.001), whereas the correlation between HDL3 cholesterol and k2 was negative (r = -0.37, P less than 0.05). These findings extend other observations indicating that HDL2 seems to be the HDL fraction, directly associated with removal of TG-rich particles from the circulation.