Hepatic lipase often found bound to HSPG, heparan sulfate proteoglycans (HSPG), keeping HL inactive and unable to bind to HDL (high density lipoprotein) or IDL (intermediate density lipoprotein). When it is free in the bloodstream, however, it is found associated with HDL to maintain it inactive. This is because the triacylglycerides in HDL serve as a substrate, but the lipoprotein contains proteins around the triacylglycerides that can prevent the triacylglycerides from being broken down by HL. One of the principal functions of hepatic lipase is to convert intermediate-density lipoprotein (IDL) to low-density lipoprotein (LDL). Hepatic lipase thus plays an important role in
Proper adjective Proper adjective In English orthography, the term proper adjective is sometimes applied to adjectives that take initial capital letters, and the term common adjective to those that do not. For example, a person from Boston is Bostonian. "Bostonian" is a proper adjective. These terms are used informally only; they are not used by grammarians or linguists. The term "proper noun" denotes a noun that, grammatically speaking, identifies a specific unique entity; for example, "England" is a proper noun, because it is a name for a specific country, whereas "dog" is not a proper noun; it is, rather, a "common noun"