Abel, John Jacob (1857–1938)
American biochemist, best known for his first identification (1898) of a
hormone, adrenaline (epinephrine). Abel
was professor of pharmacology (1893–1932) at Johns Hopkins University.
He made his key discovery after many years of studying the chemical composition
of body tissues, finally isolating the hormone from the suprarenal glands
of sheep. Later, Abel isolated amino acids from blood by the process of dialysis,
and discovered insulin in crystalline form.