Effect of catecholamine depletion on lithium-induced long-term remission of bipolar disorder.
BACKGROUND
This study investigated the effects of catecholamine depletion with alpha-methylparatyrosine (AMPT) on mood indices in patients with bipolar disorder who were in long-term remission with lithium therapy.


METHODS
Eight subjects with DSM-IV bipolar disorder currently in remission for > 3 months on lithium were included in the study. Subjects were given either AMPT or placebo, in a randomized double-blind manner, in two test sessions of 4 days each.


RESULTS
Subjects did not have any significant changes in mood during AMPT or placebo administration; however, 24-48 hours after the last active AMPT dose subjects had a transient relapse of hypomanic symptoms. Relapse of hypomanic symptoms did not correlate with increases in serum levels of homovanillic acid or 3-methoxy-4-hydroxyphenylglycol.


CONCLUSIONS
These findings suggest that the mechanism of prevention of manic relapse by long-term lithium therapy may be dependent on stability of the catecholamine system.
Anand
A
A
Department of Psychiatry, Yale University School of Medicine, New Haven, Connecticut, USA.
Darnell
A
A
Miller
H L
HL
Berman
R M
RM
Cappiello
A
A
Oren
D A
DA
Woods
S W
SW
Charney
D S
DS
D000328:Adult; D018692:Antimanic Agents / Q000627:therapeutic use*; D001714:Bipolar Disorder / Q000175:diagnosis / Q000188:drug therapy* / Q000378:metabolism* / Q000517:prevention & control; D002395:Catecholamines / Q000378:metabolism*; D004311:Double-Blind Method; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D005260:Female; D006719:Homovanillic Acid / Q000097:blood / Q000378:metabolism; D006801:Humans; D008094:Lithium / Q000627:therapeutic use*; D008297:Male; D008734:Methoxyhydroxyphenylglycol / Q000097:blood / Q000378:metabolism; D008875:Middle Aged; D011569:Psychiatric Status Rating Scales; D012008:Recurrence; D012074:Remission Induction; D012720:Severity of Illness Index; D013997:Time Factors; D019805:alpha-Methyltyrosine / Q000494:pharmacology*
D018692:Antimanic Agents; D002395:Catecholamines; D004791:Enzyme Inhibitors; D008734:Methoxyhydroxyphenylglycol; D019805:alpha-Methyltyrosine; D008094:Lithium; D006719:Homovanillic Acid