L-Tetrahydropalmatine (L-THP)
L-Tetrahydropalmatine (L-THP) is the levorotatory enantiomer of tetrahydropalmatine, a tetracyclic protoberberine-type isoquinoline alkaloid isolated from plants of the Corydalis and Stephania genera. As an isolated stereoisomer, L-THP is utilized in receptor-based research due to the distinct pharmacological activity of the (−)-enantiomer compared to its racemate or the (+)-enantiomer. It is primarily used as a multi-receptor probe in monoamine receptor research.
Physical & Handling Properties
| Property | Specification |
|---|---|
| Appearance | White to off-white crystalline powder |
| Solubility | Poor in water; soluble in DMSO and organic solvents |
Pharmacology & Research Context
L-THP is characterized by broad, moderate-affinity engagement across multiple monoamine receptor families, acting as an antagonist at dopamine D1, D2, and D3 receptors, with additional affinity at α-adrenergic and serotonergic sites. Consequently, it functions effectively as a multi-receptor probe in in vitro assays rather than a highly selective tool compound.
Safety Warning: Hepatotoxicity
L-THP is a documented cause of drug-induced liver injury. It has been associated with cases of acute hepatitis and, in historical contexts involving traditional preparations, serious toxicological events. L-THP is not FDA-approved for any indication. Investigators should treat this compound as a known hepatotoxin and utilize appropriate laboratory safety protocols when handling.
Research Applications
L-THP is utilized for its role in investigating dopaminergic signaling and monoamine receptor dynamics.
Primary fields of in vitro laboratory investigation include:
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Receptor Binding Studies: Mapping affinity profiles across dopamine, adrenergic, and serotonergic receptor families.
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Monoamine System Probing: Utilizing the compound as a multi-receptor agent in neurobiological cell models.
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Structural/Enantiomeric Analysis: Comparative research between L-THP, the racemate, and the (+)-enantiomer.
Storage & Handling Guidelines
Store at controlled room temperature. Keep tightly closed.
Storage guidance is a house recommendation. Analytical documentation is per-lot release testing.
Related Research Compounds
Research Use Disclaimer
Research Use Only Disclaimer: This product is labeled and sold “For Research Use Only — NOT FOR HUMAN CONSUMPTION.” It is not a drug, dietary supplement, food, cosmetic, or medical device, and it is not approved by the FDA or any other regulator for human or veterinary use. It is supplied to approved account holders as a research chemical for laboratory use and must be handled in accordance with applicable law.
