Electrophoretic Profiles of Serum Lipoproteins in Hyperlipidemias

With the development of a practical method of polyacrylamide gel (PAG) electrophoresis of serum lipoproteins, sophisticated studies on serum lipid or lipoprotein disorders in atherosclerotic cardiovascular patients became possible. Qualitative and quantitative disorders of serum lipoproteins are estimated adequately even in modest to moderate hyperlipidemias which are quite prevalent among atherosclerotic cardiovascular patients. The objective of this presentation is to relate electrophoretic profiles of serum lipoproteins worked out with PAG disc method on an approximately 1815 clinical subjects.Serum lipoprotein PAG disc electrophoretic profiles could be classified as six basic lipoprotein patterns. Four of six basic patterns seemed being consistent with the patterns of four of the established cases with familia hyperlipoproteinemia of WHO and other classifications, though none of our subjects had any clinical evidence of familial disorders. Presence of the midband lipoproteins and chylomicrons were major sources of a considerable number of the variations of the six basic patterns.Occurrence of dense and wide midband was relatively rare in hyperpre-bata lipoproteinemia. In this abnormality, fluctuation of serum triglyceride concentration is evidently ascribable to chylomicrons which is clearly separated from pre-beta or beta lipoproteins with PAG method. The mixed hyperlipoproteinemia (referred to as the sixth phenotype by some) is detectable and identifiable with the method. Lipid chemistry of this abnormality was frequently indif f erentiable from those of other hyperlipoproteinemias. Dense and wide midband was detected frequently among hyperbeta lipoproteinemia with or without. moderately detectable pre-beta lipoprotein, though occurrence of the midband per se was not differred from the others. The midband showed considerable variations in electrophoretic characters. Hypercholesterolemia was common in these subjects, but triglyceride level was variable. Among the variations of normal lipoprotein pattern, the most interesting was those with dense and wide midband in addition to normal beta lipoprotein band. Some of them showed hypercholesterolemia and some others showed hypertriglyceridemia. Following drug therapy for hyperlipidemia, quantitative and qualitative changes of serum lipoprotein profiles were observable frequently.These observations suggest that serum lipid abnormalities may appear as variable forms of abnormal spectra of lipoprotein species, although there is a rough interrelationship between serum lipoprotein abnromalities and lipid abnormalities.