title: Effects of melatonin on prepulse inhibition, habituation and sensitization of the human startle reflex in healthy volunteers.
abstract: Prepulse inhibition of the startle reflex (PPI) is an operational measure of sensorimotor gating, which is demonstrated to be impaired in patients with schizophrenia. In addition, a disruption of the circadian rhythm together with blunted melatonin secretion is regularly found in patients with schizophrenia and it is theorized that these may contribute to their attentional deficits. The aim of this study was to assess the effects of acute melatonin on healthy human sensorimotor gating. Twenty-one healthy male volunteers were administered melatonin or placebo after which their levels of PPI were assessed. Melatonin significantly reduced startle magnitude and ratings of alertness, but did not influence PPI, nor sensitization and habituation. However, when taking baseline scores in consideration, melatonin significantly increased PPI in low scoring individuals while significantly decreasing it in high scoring individuals in low intensity prepulse trialtypes only. In addition, subjective ratings of alertness correlated with PPI. The results suggest that melatonin has only minor influences on sensorimotor gating, habituation and sensitization of the startle reflex of healthy males. The data do indicate a relationship between alertness and PPI. Further research examining the effects of melatonin on these processes in patients with schizophrenia is warranted.
authors.affiliation: Center for Neuropsychiatric Schizophrenia Research (CNSR), Copenhagen University Hospital, Psychiatric Center Glostrup, Ndr. Ringvej 29-67, DK-2600 Glostrup, Denmark; Center for Clinical Intervention and Neuropsychiatric Schizophrenia Research (CINS), Copenhagen University Hospital, Psychiatric Center Glostrup, Denmark; Faculty of Pharmaceutical Sciences, University of Copenhagen, Denmark.
authors.forename: Emilia K
authors.initials: EK
authors.lastname: Lehtinen
authors.affiliation: Center for Neuropsychiatric Schizophrenia Research (CNSR), Copenhagen University Hospital, Psychiatric Center Glostrup, Ndr. Ringvej 29-67, DK-2600 Glostrup, Denmark; Center for Clinical Intervention and Neuropsychiatric Schizophrenia Research (CINS), Copenhagen University Hospital, Psychiatric Center Glostrup, Denmark; Faculty of Pharmaceutical Sciences, University of Copenhagen, Denmark.
authors.forename: Ebru
authors.initials: E
authors.lastname: Ucar
authors.affiliation: Center for Neuropsychiatric Schizophrenia Research (CNSR), Copenhagen University Hospital, Psychiatric Center Glostrup, Ndr. Ringvej 29-67, DK-2600 Glostrup, Denmark; Center for Clinical Intervention and Neuropsychiatric Schizophrenia Research (CINS), Copenhagen University Hospital, Psychiatric Center Glostrup, Denmark; Faculty of Health Sciences, Dept. of Neurology, Psychiatry, and Sensory Sciences, University of Copenhagen, Denmark.
authors.forename: Birte Y
authors.initials: BY
authors.lastname: Glenthøj
authors.affiliation: Center for Neuropsychiatric Schizophrenia Research (CNSR), Copenhagen University Hospital, Psychiatric Center Glostrup, Ndr. Ringvej 29-67, DK-2600 Glostrup, Denmark; Center for Clinical Intervention and Neuropsychiatric Schizophrenia Research (CINS), Copenhagen University Hospital, Psychiatric Center Glostrup, Denmark; Faculty of Health Sciences, Dept. of Neurology, Psychiatry, and Sensory Sciences, University of Copenhagen, Denmark; NICHE, Department of Psychiatry, Brain Center Rudolf Magnus, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX, Utrecht, The Netherlands. Electronic address: B.Oranje@cnsr.dk.
authors.forename: Bob
authors.initials: B
authors.lastname: Oranje
mesh_terms: D000293:Adolescent; D000328:Adult; D001288:Attention / Q000187:drug effects / Q000502:physiology; D018592:Cross-Over Studies; D006185:Habituation, Psychophysiologic / Q000187:drug effects* / Q000502:physiology*; D064368:Healthy Volunteers; D006801:Humans; D008297:Male; D008550:Melatonin / Q000494:pharmacology*; D013216:Reflex, Startle / Q000187:drug effects* / Q000502:physiology*; D012559:Schizophrenia / Q000503:physiopathology; D055139:Sensory Gating / Q000187:drug effects* / Q000502:physiology*; D055815:Young Adult
chemical_list: D008550:Melatonin
keywords: Electromyography; Orbicularis oculi muscle; PPI; Schizophrenia; Sensorimotor gating