Macromolecules, endogenous

Toxic reactions occur by several mechanisms activation of metabolism, production of reactive intermediates and subsequent reactions with cell macromolecules, changing receptor responses, or through abnormal defence reactions. Several compounds cause toxicity by mimicking the organism s own hormones or neurotransmitters, or activating the body s endogenous receptors in some non-physiological way. ... 

Receptor. A macromolecule with which a drug or endogenous substance interacts to produce its effect. 

Lipoproteins. A lipoprotein is an endogenous macromolecule consisting of an inner apolar core of cholesteryl esters and triglycerides surrounded by a monolayer of phospholipid embedded with cholesterol and apoproteins. The functions of lipoproteins are to transport lipids and to mediate lipid metabolism. There are four main types of lipoproteins (classified based on their flotation rates in salt solutions) chylomicrons, very-low-density lipoprotein (VLDL), low-density lipoprotein (LDL), and high-density lipoprotein (HDL). These differ in size, molecular weight, and density and have different lipid, protein, and apoprotein compositions (Table 11). The apoproteins are important determinants in the metabolism of lipoproteins—they serve as ligands for lipoprotein receptors and as mediators in lipoproteins interconversion by enzymes. 

At the cellular level, plant secondary metabolites have five major effects on herbivores (a) alteration of DNA replication, RNA transcription, and protein synthesis (b) alteration of membrane transport processes (c) enzyme inhibition and activation (d) blocking of receptor sites for endogenous chemical transmitters and (e) affecting the conformation of other macromolecules (Robinson, 1979). 

Know how to manipulate the body s endogenous macromolecules (chapters 7 and 8). 

Nonmessenger targets drugs that target endogenous macromolecules (chapter 8)... 

Endogenous macromolecules as nonmessenger targets (e.g., carbonic anhydrase inhibitors or other agents as diuretics, chapter 8)... 

These seven groups of endogenous nonmessenger macromolecules offer a plethora of leads as both drugs and druggable targets (see figure 8.5). In a somewhat arbitrary but... 

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