In Vitro Effects of St. John's Wort Extract and Hyperforin
on 5 HT Uptake and Efflux in Human Blood Platelets

Introduction

To obtain more information on the mechanisms giving Hypericum perforatum L. (St. John's wort, SJW) its antidepressant-like properties, we investigated the in vitro effects of SJW extract and pure hyperforin on human blood platelet 5 HT uptake and 5 HT efflux and compared them to amitriptyline (AMI), venlafaxine (VEN) and reserpine.

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