gerontine

from The Century Dictionary.

• noun A colorless, crystalline base, C₅H₁₄N₂, obtained from the liver and kidneys, especially from those of old dogs. It is isomeric with cadaverine, which it resembles.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun biochemistry, archaic A substance isolated from liver, later identified as spermine.