In the majority of mammals, the liver is rich in ascorbic acid because of ascorbate synthesis in that organ. Moreover, in humans, apes, monkeys, and guinea pigs, which cannot synthesize ascorbic acid, the liver receives this vitamin directly from the portal vein blood after absorption from the gastrointestinal tract. The liver normally constitutes the largest store of ascorbic acid in the body, but when dietary ascorbic acid is discontinued, the guinea pig liver ascorbic acid level falls rapidly.