Glossary

Electrocardiogram (EKG or ECG)
A graphic record of the heart's action produced by an electrocardiograph and used for diagnostic purposes.
Electrocardiograph
Device that records the electrical activity of the heart over time.
Endocrine
Cell signaling performed by the secretion of chemicals which are carried by the blood and tissue fluids to target cells.
Endocrine gland
Glands that regulate physiological functions in your body with the hormones they produce.
Endocrine system
System of glands which release hormones directly into the circulatory system to help to control metabolic activity. The endocrine system controls slow, long‑lasting responses to internal stimuli.
Endocrinology
The science of hormone function.
Endogenous
Produced or synthesized within the organism or system.
Enzyme
A protein (or protein‑based molecule) that speeds up a chemical reaction in a living organism.
Epidemic
Sudden outbreak of infectious disease or other health related event that occurs in numbers exceeding normal expectancy.
Epidemiological
Relating to the study of the causes, distribution, and control of disease in populations.
Ergocalciferol
Vitamin D2. A vitamin D‑like, patented drug that is not naturally present in the human body. It is derived from fungal and plant sources by activating ergosterol with ultraviolet light. It is only half as potent as cholecalciferol (real vitamin D) and may even block some of cholecalciferol's beneficial effects. It is more toxic and is the cause of most of the reported cases of vitamin D toxicity.
Ergometer
A device which measures the amount of energy or work performed.
Ergosterol
Precursor to ergocalciferol (Vitamin D2). A component of fungal cell membranes which serves the same function in plants that cholesterol does in animals.
Estrogen
Steroid hormone present in both men and women, usually at higher levels in women of reproductive age.
Experimental autoimmune encephalomyelitis (EAE)
An experimental model of brain inflammation that mimics, to some degree, the inflammation that occurs in multiple sclerosis (MS).