Effects of hypericum extract (LI 160) in biochemical models of antidepressant activity.
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 micrograms/ml). Moreover, subchronic treatment of rats with hypericum extract led to a significant down-regulation of beta-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).
Müller
W E
WE
Department of Pharmacology, Biocenter University of Frankfurt, Germany.
Rolli
M
M
Schäfer
C
C
Hafner
U
U
D018759:Adrenergic Uptake Inhibitors / Q000494:pharmacology; D000818:Animals; D000928:Antidepressive Agents / Q000378:metabolism / Q000494:pharmacology*; D000929:Antidepressive Agents, Tricyclic / Q000494:pharmacology; D001921:Brain / Q000201:enzymology; D003863:Depression / Q000378:metabolism*; D018765:Dopamine Uptake Inhibitors / Q000494:pharmacology; D005260:Female; D020902:Hypericum; D007099:Imipramine / Q000494:pharmacology; D051379:Mice; D008995:Monoamine Oxidase / Q000378:metabolism; D010569:Perylene / Q000031:analogs & derivatives* / Q000378:metabolism / Q000494:pharmacology; D010946:Plants, Medicinal; D017397:Prefrontal Cortex / Q000187:drug effects / Q000378:metabolism; D011794:Quercetin / Q000031:analogs & derivatives* / Q000378:metabolism / Q000494:pharmacology; D051381:Rats; D011943:Receptors, Adrenergic, beta / Q000187:drug effects / Q000378:metabolism; D011985:Receptors, Serotonin / Q000187:drug effects / Q000378:metabolism; D017367:Selective Serotonin Reuptake Inhibitors / Q000494:pharmacology; D013574:Synaptosomes / Q000378:metabolism; D014966:Xanthenes / Q000378:metabolism / Q000494:pharmacology*
D018759:Adrenergic Uptake Inhibitors; D000928:Antidepressive Agents; D000929:Antidepressive Agents, Tricyclic; D018765:Dopamine Uptake Inhibitors; D007099:Imipramine; D008995:Monoamine Oxidase; D010569:Perylene; D011794:Quercetin; D011943:Receptors, Adrenergic, beta; D011985:Receptors, Serotonin; D017367:Selective Serotonin Reuptake Inhibitors; D014966:Xanthenes