EDTA
Ethylenediaminetetraacetic acid.
ELISA
Enzyme-linked immunosorbent assay. A microtiter-based, immunochemical technique to detect and quantitate levels of a protein with an antibody against that protein (
Antigen).
EM
Extensive metabolizer. A term used to distinguish individuals who express an enzyme from those who, for genetic reasons, do not. The latter individuals are known as PM, for poor metabolizers.
endobiotic
An endogenous substance, as opposed to a xenobiotic (a foreign substance). The same hepatic enzymes that biotransform xenobiotics (such as drugs) also biotransform certain endobiotics (such as steroid hormones).
endoplasmic reticulum
Intracellular membranes that contain cytochrome P450 and other drug-metabolizing enzymes. During tissue homogenization, the endoplasmic reticulum vesiculates and forms microsomes.
enterocyte
A type of intestinal epithelial cell. The majority of metabolic enzymes within the intestine are contained in the mature enterocytes found at the apices of the intestinal villi.
enzyme mapping
See
Reaction Phenotyping.
enzymes
Biological catalysts (proteins) that speed up chemical reactions.
ex vivo
A combination of
in vivo and
in vitro techniques whereby animals are treated
in vivo, followed by an
in vitro analysis of the effects of the treatment.
Organs and tissues other than the liver. Non-hepatic drug metabolism is often called extrahepatic metabolism.