Effet De LaS-Adenosyl-L-Homocysteine Sur Le Catabolisme De La Dopamine

Abstract

The administration of SAH [S-adenosyl-L-homocysteine] to rats, at doses physiologically active on sleep, does not change the urinary level of MD [3-O-methyldopamine] and NM [normetanephrine]. The excretion of DA [dopamine] and NA [norepinephrine] decreases. In the brain, SAH does not modify the concentration of NA and NM in hypothalamus and thalamus, or the concentration of DA and MD in corpus striatum. After intracisternally injection of [14C]DA or [3H]NA, SAH increases the level of [14C]MD and [3H]NM. Contrary to the studies in vitro, where SAH is an inhibitor of COMT [catechol-O-methyltransferase] in the rat it does not seem to prevent the methylation of DA and NA.