抄録
Eel hepatocytes actively syntesize and secrete a lipoprotein. It consists of about 60% triacylglyceroi and 10% protein, and main apolipoproteins are apoB and apoA. Its average particle size is 750 nm. These characteristics show it is a chylomicron llike lipoprotein. Thyroxin (T 4) at 10-8M activates the lipid synthesis in the hepatocytes and increases hepatocellular lipid. The synthesis of the chyloimicron Ilike lipoprotein is also stimulated by T 4, but T 4 does not affect the synthesis of other secreted proteins. T 4 specifically stimulates the synthesis of the lipoprotein. Though docosahexaenoic acid (DHA) stimulates lipid synthesis in the hepatocytes, DHA inhibits the synthesis and secretion of the lipoprotein. However, DHA does not in hibit the synthesis of other secreted proteins. DHA specifically in hibits the synthesis and secretion of the lipoprotein, but eicosapentaenoic acid does not in hibit HDL specifically binds HDL -binding protein (HBP) of the plasma membrane. The binding of HDL to the hepatocytes is saturated at concentrations over 100 μg HDL/ml and Kd value is 20 μg HDL/ml. HDL and apoAl are ligands of HBP. We suppose that HDL and free apoAl in eel serum take part in lipid transport through the mediation of the HBP.
