Plasma lecithin:cholesterol acyltransferase -- reference values and effects of xenobiotics.

Plasma lecithin:cholesterol acyltransferase (LCAT) has been measured by an enzymatic method. We did not observe any significant sex variations, but age variations were found. In females, LCAT activities are stable up to 40 years (60 mumol . 1.1 . h-1 at the 50th centile). Also, from 50 years the median increased progressively to 76 mumol . 1-1 . h-1. In males, the activity increased from 52 to 71 mumol . 1-1 . h-1 at the 50th centile in two age groups (15-20 years and 50 years). The effect of some xenobiotics on LCAT activity was studied. We observed an increase in activity of 33% in males when the daily alcoholic beverage consumption ranged from 0 to more than 0.5 litre of wine or beer. LCAT activity increased in children who were treated with hypolipidemic drugs (fenofibrate, Lipanthyl). In boys, the mean enzyme activity increased to 35% (p less than 0.05). The increase was greater in girls (75%, p less than 0.01). Treatment with anticonvulsant drugs gave a decrease in LCAT activity of 32-46%.