Desmethylimipramine treatment increases melatonin production in humans

Abstract

Melatonin is produced by the pineal gland, mainly at night in the dark. Melatonin secretion by the pineal gland is an attractive model for the in vivo study of adrenergic pharmacology in humans (Lewy 1983. 1984). Unlike most autonomically regulated organs. the pineal gland appears to receive only postganglionic sympathetic innervation (there is no antagonistic cholinergic input) (Schrier and Klein 1974; Ariens Kappers et al. 1979). The pineal does not participate in the stress response, thus eliminating a common source of artifact (reviewed by Vaughn 1984). There do not appear to be extrapineal sources of plasma melatonin in humans (Neuwelt and Lewy 1983). For a given individual. night-tonight melatonin production is very consistent (Sack et al. 1985); thus, drug-induced alterations in melatonin production are readily detectable. Melatonin production is affected by drugs with well-established adrenergic activity; for example. beta-adrenergic blockers potently suppress melatonin production (Hanssen et al.