Decreases in apolipoprotein(a) after renal transplantation: implications for lipoprotein(a) metabolism.
Serum concentrations of apolipoprotein(a) [apo(a)], the unique glycoprotein of lipoprotein(a), are increased in patients with end-stage renal failure. We prospectively studied serum apo(a) and other lipoproteins in 20 consecutive patients, ages 46 +/- 11 years, before and for six months after successful renal transplantation. All patients received cyclosporine, and no patient was treated for hyperlipidemia. The mean creatinine clearance increased from 7.5 mL/min before transplant surgery to 40.9 mL/min six months afterwards (P less than 0.001). Apo(a) decreased from a median of 403 units/L before transplantation to 184 units/L at one week (P less than 0.001) and was 170 units/L (P less than 0.001) at six months. For the assay used, 1 unit of apo(a) is equivalent to 1 mg of lipoprotein(a). In contrast, from baseline to six months, increases were found for low-density lipoprotein (LDL) cholesterol (P = 0.03), high-density lipoprotein cholesterol (P = 0.06), apo B (P = 0.07), and apo A-I (P = 0.01). The decrease in apo(a) in individual patients was significantly correlated with the increase in creatinine clearance (r = -0.48, P less than 0.001). The single patient who developed nephrotic syndrome after renal transplantation had marked increases in apo(a) (693-1595 units/L), apo B, and LDL cholesterol, which paralleled the degree of proteinuria. These findings suggest that abnormal renal function affects the regulation of lipoprotein(a) metabolism.
Black
I W
IW
Department of Cardiovascular Medicine, Prince Henry Hospital, University of New South Wales, Sydney, Australia.
Wilcken
D E
DE
D000328:Adult; D016632:Apolipoprotein A-I / Q000378:metabolism; D001054:Apolipoproteins A / Q000378:metabolism*; D001055:Apolipoproteins B / Q000097:blood; D008076:Cholesterol, HDL / Q000097:blood; D008078:Cholesterol, LDL / Q000097:blood; D005260:Female; D006801:Humans; D007676:Kidney Failure, Chronic / Q000097:blood*; D016030:Kidney Transplantation; D008297:Male; D008875:Middle Aged; D009404:Nephrotic Syndrome / Q000097:blood; D011446:Prospective Studies; D014280:Triglycerides / Q000097:blood
D016632:Apolipoprotein A-I; D001054:Apolipoproteins A; D001055:Apolipoproteins B; D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D014280:Triglycerides