Tetrahydropalmatine

Drugbox
IUPAC_name = (13aS)-2,3,9,10-tetramethoxy-6,8,13,13a-tetrahydro-5H-isoquinolino [2,1-b] isoquinoline

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CAS_number = 10097-84-4
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PubChem = 72301
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chemical_formula =
C=21 | H=25 | N=1 | O=4
molecular_weight = 355.428 g/mol
smiles = COC1=C(C2=C(C [C@H] 3C4=CC(=C(C=C4CCN3C2)OC)OC)C=C1)OC
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Tetrahydropalmatine (THP) is an alkaloid found in several different plant species, mainly in the "Corydalis" family, [Chen JJ, Duh CY, Chen IS. New tetrahydroprotoberberine N-oxide alkaloids and cytotoxic constituents of Corydalis tashiroi. "Planta Medica". 1999 Oct;65(7):643-7. PMID 17260290] [Ma ZJ, Li XD, Gu XZ, Cheng LP, Mao SJ. Effects of different types and standard of processing vinegaron inherent constituents in rhizoma of Corydalis yanhusuo. (Chinese). "Zhongguo Zhong Yao Za Zhi". 2006 Mar;31(6):465-7. PMID 16722373] but also in other plants such as "Stephania rotunda". [Chea A, Hout S, Bun SS, Tabatadze N, Gasquet M, Azas N, Elias R, Balansard G. Antimalarial activity of alkaloids isolated from Stephania rotunda. "Journal of Ethnopharmacology". 2007 May 30;112(1):132-7. PMID 17382502] These plants have traditional uses in Chinese herbal medicine. The pharmaceutical industry has synthetically produced the more potent enantiomer Levo-tetrahydropalmatine (Levo-THP), which has been marketed worldwide under different brand names as an alternative to anxiolytic and sedative drugs of the benzodiazepine group and analgesics such as opiates. It is also sold as a dietary supplement.

Effects

Tetrahydropalmatine has been demonstrated to possess analgesic effects and may be beneficial in the treatment of heart disease and liver damage. [Wu L, Ling H, Li L, Jiang L, He M. Beneficial effects of the extract from Corydalis yanhusuo in rats with heart failure following myocardial infarction. "Journal of Pharmacy and Pharmacology". 2007 May;59(5):695-701. PMID 17524235] [Min Q, Bai YT, Shu SJ, Ren P. Protective effect of dl-tetrahydropalmatine on liver injury induced by carbon tetrachloride in mice. (Chinese). "Zhongguo Zhong Yao Za Zhi". 2006 Mar;31(6):483-4, 521. PMID 16722379] It has also shown useful effects in the treatment of drug addiction to both cocaine and opiates, and preliminary human studies have shown promising results. [Mantsch JR, Li SJ, Risinger R, Awad S, Katz E, Baker DA, Yang Z. Levo-tetrahydropalmatine attenuates cocaine self-administration and cocaine-induced reinstatement in rats. "Psychopharmacology (Berlin)". 2007 Jul;192(4):581-91. PMID 17361394] [Chu H, Jin G, Friedman E, Zhen X. Recent development in studies of tetrahydroprotoberberines: mechanism in antinociception and drug addiction. "Cellular and Molecular Neurobiology". 2008 Jun;28(4):491-9. PMID 17710533] [Yang Z, Shao YC, Li SJ, Qi JL, Zhang MJ, Hao W, Jin GZ. Medication of l-tetrahydropalmatine significantly ameliorates opiate craving and increases the abstinence rate in heroin users: a pilot study. "Acta Pharmacologica Sinica". 2008 Jul;29(7):781-8. PMID 18565275]

Animal experiments have shown that the sedative effect of THP results from blocking dopaminergic neurons in the brain. Dopamine is one of the most important neurotransmitters in the central nervous system where it occurs in several important systems that regulate muscular activity and attention, as well as feelings of joy, enthusiasm and creativity. Therefore, THP causes no feelings of euphoria, and has been seen as an alternative to addictive drugs for people suffering from anxiety and pain, and as a possibility for relief for people not helped by existing drugs.

Cases of poisoning

However, several cases of poisoning related to THP have also been reported. [Lai, Chi-Kong and Yan-Wo Chan, Albert (1999) "Tetrahydropalmatine Poisoning: Diagnoses of Nine Adult Overdoses Based on Toxicology Screens by HPLC with Diode-Array Detection and Gas Chromatography–Mass Spectrometry" in "Clinical Chemistry" 45:2, pp 229 - 236.] These cases involved negative effects on respiration, cardiac activity and the nervous system. In addition, chronic hepatitis has been reported, caused by THP production in East Asia under conditions that were insufficiently sterile. Fatalities started to be reported in 1999 in cases where THP had been used in combination with other drugs having analgesic and anti-anxiety effects. All 1999 deaths could be tied to a single THP-based supplement, sold under the name "Jin Bu Huan Anodyne Tablets". This product was therefore blacklisted by US and European health authorities. In some other countries, such as Singapore, THP is treated as a controlled substance, and license is required to sell it.

ee Also

*Apomorphine
*Bulbocapnine
*Glaucine
*Nuciferine
*Pukateine
*Stepholidine

References