Pharmacopsychiatry 1997; 30: 102-107
DOI: 10.1055/s-2007-979528
Original Papers

© Georg Thieme Verlag Stuttgart · New York

Effects of Hypericum Extract (LI 160) in Biochemical Models of Antidepressant Activity

W. E. Müller1 , 2 , M. Rolli2 , C. Schäfer2 , U. Hafner2
  • 1Department of Pharmacology, Biocenter University of Frankfurt, Frankfurt, Germany
  • 2Department of Psychopfiarmacology, Central Institute of Mental Health, Mannheim, Germany
Further Information

Publication History

Publication Date:
20 April 2007 (online)

Since the mechanism of the antidepressant activity of hypericum extract is not yet understood, we tested possible effects of standardized hypericum extract (LI 160) in several biochemical models relevant for the mechanism of action of other antidepressant drugs. While LI 160 was only a weak inhibitor of MAO-A and MAO-B activity, it inhibited the synaptosomal uptake of serotonin, dopamine and norepinephrine with about equal affinity ~ 2 μg/ml). Moreover, subchronic treatment of rats with hypericum extract led to a significant down-regulation of β-receptors and to a significant up-regulation of 5-HT2-receptors in the frontal cortex. The data might suggest that hypericum extract acts via similar biochemical mechanisms to other antidepressants (e.g. tricyclics).