D-Tetrahydropalmatine is an isoquinoline alkaloid, mainly in the genus Corydalis[1]. D-Tetrahydropalmatine is a Dopamine (DA) receptor antagonist with preferential affinity toward the D1 receptors[2]. D-Tetrahydropalmatine is a potent organic cation transporter 1 (OCT1) inhibitor[3].
[1]. Ma ZJ, et al. [Effects of different types and standard of processing vinegaron inherent constituents in rhizoma of Corydalis yanhusuo]. Zhongguo Zhong Yao Za Zhi. 2006 Mar;31(6):465-7. [2]. Xu SX, et al. Effects of tetrahydroprotoberberines on dopamine receptor subtypes in brain. Zhongguo Yao Li Xue Bao. 1989 Mar;10(2):104-10. [3]. Tu M, et al. Organic cation transporter 1 mediates the uptake of monocrotaline and plays an important rolein its hepatotoxicity. Toxicology. 2013 Sep 15;311(3):225-30.