Hepatic lipase (HL) is a lipolytic enzyme synthesized in liver parenchymal cells. It is present on the
surface of the liver sinusoidal endothelial cells and the surface of the hepatocyte microvilli in the
sinusoidal space, and can hydrolyze various lipoproteins. The triglycerides (TG) and phospholipids (PL) in
the medium change the size and density of various lipoprotein particles. When the HL and its activity in
the plasma increasing, it can lead to low density lipoprotein (LDL) levels in the plasma, increase and
accelerate the occurrence and development of atherosclerosis.
HL hydrolyzes α-naphthyl acetate to produce α-naphthol, which can form a purple-red azo compound with
fast blue B salt. It has a characteristic absorption peak at 595 nm, and its color depth is positively
correlated with liver esterase activity within a certain range.
Reagents and Equipment Required but Not Provided:
Spectrophotometer, water bath, balance, centrifuge, adjustable transferpettor, 1 mL glass cuvette,
mortar/homogenizer, ultrasonic crusher, ice and distilled water.