RATIONALE: The loudness dependence of the auditory evoked potential (LDAEP) is considered a noninvasive in vivo marker of central serotonergic functioning in humans. Nevertheless, results of genetic association studies point towards a modulation of this biomarker by dopaminergic neurotransmission. OBJECTIVE: We examined the effect of dopaminergic modulation on the LDAEP using L-3,4-dihydroxyphenylalanine (levodopa)/benserazide (Madopar®) as a challenge agent in healthy volunteers. METHODS: A double-blind placebo-controlled challenge design was chosen. Forty-two healthy participants (21 females and 21 males) underwent two LDAEP measurements, following a baseline LDAEP measurement either placebo or levodopa (levodopa 200 mg/benserazide 50 mg) were given orally. Changes in the amplitude and dipole source activity of the N1/P2 intensities (60, 70, 80, 90, and 100 dB) were analyzed. RESULTS: The participants of neither the levodopa nor the placebo group showed any significant LDAEP alterations compared to the baseline measurement. The test-retest reliability (Cronbachs Alpha) between baseline and intervention was 0.966 in the verum group and 0.759 in the placebo group, respectively. CONCLUSIONS: The administration of levodopa showed no effect on the LDAEP. These findings are in line with other trials using dopamine receptor agonists.
RCT Entities:
RATIONALE: The loudness dependence of the auditory evoked potential (LDAEP) is considered a noninvasive in vivo marker of central serotonergic functioning in humans. Nevertheless, results of genetic association studies point towards a modulation of this biomarker by dopaminergic neurotransmission. OBJECTIVE: We examined the effect of dopaminergic modulation on the LDAEP using L-3,4-dihydroxyphenylalanine (levodopa)/benserazide (Madopar®) as a challenge agent in healthy volunteers. METHODS: A double-blind placebo-controlled challenge design was chosen. Forty-two healthy participants (21 females and 21 males) underwent two LDAEP measurements, following a baseline LDAEP measurement either placebo or levodopa (levodopa 200 mg/benserazide 50 mg) were given orally. Changes in the amplitude and dipole source activity of the N1/P2 intensities (60, 70, 80, 90, and 100 dB) were analyzed. RESULTS: The participants of neither the levodopa nor the placebo group showed any significant LDAEP alterations compared to the baseline measurement. The test-retest reliability (Cronbachs Alpha) between baseline and intervention was 0.966 in the verum group and 0.759 in the placebo group, respectively. CONCLUSIONS: The administration of levodopa showed no effect on the LDAEP. These findings are in line with other trials using dopamine receptor agonists.
Authors: Wolfram Kawohl; Ina Giegling; Paraskevi Mavrogiorgou; Oliver Pogarell; Christoph Mulert; Hans-Jürgen Möller; Ulrich Hegerl; Dan Rujescu; Georg Juckel Journal: Int J Neuropsychopharmacol Date: 2008-02-08 Impact factor: 5.176
Authors: Idun Uhl; Inge Gorynia; Jürgen Gallinat; Christoph Mulert; Alexander Wutzler; Andreas Heinz; Georg Juckel Journal: Hum Psychopharmacol Date: 2006-10 Impact factor: 1.672
Authors: Georg Juckel; Ulrich Hegerl; Ina Giegling; Paraskevi Mavrogiorgou; Alexander Wutzler; Christiane Schuhmacher; Idun Uhl; Martin Brüne; Christoph Mulert; Oliver Pogarell; Dan Rujescu Journal: Am J Med Genet B Neuropsychiatr Genet Date: 2008-06-05 Impact factor: 3.568