Glutamate Inhibition of the Adrenergic‐Stimulated Production of Melatonin in Rat Pineal Gland In Vitro

Laura Kus, Robert J. Handa, John A. McNulty

Research output: Contribution to journalArticlepeer-review

27 Scopus citations


Abstract: The effect of l‐glutamate on the adrenergic‐stimulated release of melatonin in the rat pineal gland was examined using an in vitro perfusion system. l‐Glutamate by itself had no effect on melatonin secretion whereas l‐glutamate administered prior to (–)‐isoproterenol (β‐adrenergic agonist) and l‐phenylephrine (α‐adrenergic agonist) inhibited melatonin production by 42%. l‐Glutamate did not inhibit melatonin secretion when glands were stimulated with (–)‐isoproterenol alone. d‐Glutamate, as well as the l‐glutamate agonists kainate, N‐methyl‐d‐aspartate, quisqualate, and trans‐1‐aminocyclopentane‐1, 3‐dicarboxylic acid, had no effect on the (–)‐isoproterenol‐and l‐phenylephrine‐stimulated secretion of melatonin, which suggests that the inhibitory effects of glutamate are not mediated via any of the known glutamate receptor subtypes. The possibility that l‐glutamate may be converted to another neuroactive compound (GABA) prior to the addition of (–)‐isoproterenol and l‐phenylephrine is suggested by the observation that simultaneous administration of l‐glutamate with (–)‐isoproterenol and l‐phenylephrine did not inhibit melatonin production.

Original languageEnglish (US)
Pages (from-to)2241-2245
Number of pages5
JournalJournal of neurochemistry
Issue number6
StatePublished - Jun 1994
Externally publishedYes


  • Excitatory amino acids
  • HPLC
  • In vitro perfusion

ASJC Scopus subject areas

  • Biochemistry
  • Cellular and Molecular Neuroscience


Dive into the research topics of 'Glutamate Inhibition of the Adrenergic‐Stimulated Production of Melatonin in Rat Pineal Gland In Vitro'. Together they form a unique fingerprint.

Cite this