The effect of presynaptic catecholamine depletion on 6-hydroxymelatonin sulfate: A double blind study of α-methyl-para-tyrosine Article

cited authors

  • Krahn, LE; Lin, SC; Klee, GG; Lu, PY; Ory, SJ; Zimmermann, RC

fiu authors


  • Because it is a competitive inhibitor of tyrosine hydroxylase, α-methyl-para-tyrosine (AMPT) is used to study psychiatric disorders. Melatonin serves as a biological marker of catecholamine function since its secretion is regulated by noradrenegic neurons via β-adrenergic receptors in the pineal gland. Ten healthy volunteers were administered AMPT in a double-blind placebo controlled study. When subjects received AMPT, nocturnal 6-hydroxymelatonin sulfate (6-SM) decreased significantly as compared with promethazine (night 1 P = 0.002; and night 2 P = 0.001). Urinary MHPG also decreased on both study days (DF1,9 F = 9.82, GG = 0.0121). Nocturnal 6-SM excretion and melatonin secretion correlated highly (r = 0.91, P = 0.0007). Behavioral ratings did not reveal a difference in symptomatology and did not correlate with changes in 6-SM or MHPG. This study demonstrates in healthy controls that 6-SM reliably reflects presynaptic catecholamine depletion induced by AMPT without the emergence of behavioral symptoms.

publication date

  • January 1, 1999

Digital Object Identifier (DOI)

start page

  • 61

end page

  • 66


  • 9


  • 1-2