The results of experiments in which intact plants of Lemna paucicostata were labeled with either l-[(3)H(3)C]methionine, l-[(14)CH(3)]methionine, or [1,2-(14)C]ethanolamine support the conclusion that growth in concentrations of choline of 3.0 micromolar or above brings about marked decreases in the rate of biosynthesis of methylated forms of ethanolamine (normally present chiefly as phosphatid...

OBJECTIVE S-Adenosylmethionine (SAMe) is a major methyl donor in the brain and is also an antidepressant with few reported side effects; however, SAMe is relatively expensive and unstable. Brain SAMe can be increased by giving methionine to rats, raising the possibility that methionine may be an antidepressant. We aimed to study whether SAMe and methionine, when given orally to rats, could rais...