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Reserpine (also known by trade names Raudixin, Serpalan, Serpasil) is an indole alkaloid,〔("Indole Alkaloids" ) ''Major Types Of Chemical Compounds In Plants & Animals Part II: Phenolic Compounds, Glycosides & Alkaloids.'' Wayne's Word: An On-Line Textbook of Natural History. 2005.〕 antipsychotic and antihypertensive drug that has been used for the control of high blood pressure and for the relief of psychotic symptoms, although because of the development of better drugs for these purposes and because of its numerous side-effects, it is rarely used today.〔() The Columbia Encyclopedia, Sixth Edition. Copyright © 2001-05 Columbia University Press.〕 The antihypertensive actions of reserpine are a result of its ability to deplete catecholamines (among other monoamine neurotransmitters) from peripheral sympathetic nerve endings. These substances are normally involved in controlling heart rate, force of cardiac contraction and peripheral vascular resistance.〔Forney, Barbara. (Reserpine for Veterinary Use ) Wedgewood Pharmacy. 2001-2002.〕 Reserpine-mediated depletion of monoamine neurotransmitters in the synapses is often cited as evidence to the theory that depletion of the monoamine neurotransmitters causes subsequent depression in humans (c.f. monoamine hypothesis). However, this claim is not without controversy. The reserpine-induced depression is considered by some researchers to be a myth, while others claim that teas made out of the plant roots containing reserpine have a calming, sedative action that can actually be considered ''anti''depressant. Notably, reserpine was the first compound shown to be an effective antidepressant in a randomized placebo-controlled trial.〔D. L. Davies and M. Shepherd, “Reserpine in the Treatment of Anxious and Depressed Patients,” The Lancet 269 (1955): 117–20〕 Moreover, reserpine has a peripheral action in many parts of the body, resulting in a preponderance of the effects of the cholinergic part of the autonomous nervous system on the GI tract, smooth muscles, blood vessels, etc. ==Mechanism of action== Reserpine irreversibly blocks the vesicular monoamine transporter (VMAT). This normally transports free intracellular norepinephrine, serotonin, and dopamine in the presynaptic nerve terminal into presynaptic vesicles for subsequent release into the synaptic cleft ("exocytosis"). Unprotected neurotransmitters are metabolized by MAO (as well as by COMT) in the cytoplasm and consequently never excite the post-synaptic cell. It may take the body days to weeks to replenish the depleted VMAT, so reserpine's effects are long-lasting. This depletion of dopamine can lead to drug-induced parkinsonism. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「reserpine」の詳細全文を読む スポンサード リンク
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