Voltage dependent L-type calcium channel inhibitor
REVIEW Tetrahydropalmatine is an racemic plant based alkaloid found in the Corydalis genus, and also in Stephania rotunda. These plants have traditional uses in Chinese herbal medicine. T he 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. L-Tetrahydropalmatine has been shown to have analgesic effects and may be beneficial in the treatment of heart disease and liver damage. It is a blocker of voltage-activated L-type calcium channel active potassium channels. It is a potent muscle relaxant. It has also shown potential in the treatment of drug addiction to both cocaine and opiates, and preliminary human studies have shown promising results.
Animal experiments have shown that the sedative effect of L- tetrahydropalmatine results from blocking dopaminergic neurons in the brain, in particular related to inhibition of D(2) dopamine receptors.. Dopamine is an important neurotransmitter in the central nervous system where it occurs in several important signaling systems that regulate muscular activity and attention, as well as feelings of joy, enthusiasm and creativity. Therefore, L-tetrahydropalmatine 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.
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