John Jacob Abel to successfully isolate the neutral base of epinephrine by adding ammonium to highly concentrated extract, a method Abel himself tried but failed due to the use of low concentration of extract. After Takamine's success, Abel himself remarked, with great candor, "The efforts of years on my part in this once mysterious field of suprarenal, medullary biochemistry, marred by blunders as they were, eventuated, then, in the isolation of the hormone not in the form of the free base but in that of its monobenzoyl derivative." Together with L.G. Rowntree and B.B. Turner, Abel devised what they called a "vividiffusion" apparatus,
Local hormone regulate activity of G-protein coupled receptors. Most often found in the pancreas and the intestines. Secretin was discovered in 1902 by E. H. Starling. It was later linked to chemical regulation and was the first substance to be deemed a hormone. 3. Mark H. Whitnall, William G. Haynes, David J. Webb (1997). Principles of Medical Biology. 4. Salmon, John A; Higgs, Gerald A (1987). "Prostaglandins and leukotrienes as inflammatory mediators". "British Medical Bulletin". 43 (2): 285–96. PMID 2825898 5. SF Gilbert. (2000). Developmental Biology 6th Edition. 6. Jan M. Keppel Hesselink.(2016). "Autacoids: A New Fundament for Pain Medicine of the