Apoproteins of high density lipoproteins in the urine of normal subjects.

Apoproteins of high density lipoproteins were detected in the urine of normal subjects after the urinary proteins were highly concentrated. By immunoelectrophoresis, all of the urinary apoproteins gave precipitin lines with similar electrophoretic mobility. This suggests that the various apoproteins are present in the same particle. The apoproteins were present only in the ultracentrifugal fraction of density greater than 1.24 g/ml. Neither apoprotein B nor apoprotein E were detected in the urine, suggesting that very low density and low density lipoproteins are not excreted in the urine of normal subjects.