Tropolone antagonism of the L-dopa-induced elevation of S-adenosylhomocysteine: S-adenosylmethionine ratio but not depletion of adrenaline in rat hypothalamus.

Abstract

Tropolone, an inhibitor of catechol O-methyl transferase, largely prevented the increase in SAH : SAMe ratio in rat hypothalamus following L-dopa injection. Tropolone did not prevent but instead enhanced the decrease produced by L-dopa of adrenaline concentration in rat hypothalamus. The results imply that the decrease in hypothalamic adrenaline concentration following L-dopa injection was not caused by the increase in SAH : SAMe ratio.