Chueh F Y, Hsieh M T, Chen C F, Lin M T
Institute of Chinese Pharmaceutical Sciences, China Medical College, Taichung City, Taiwan.
Pharmacology. 1995 Oct;51(4):237-44. doi: 10.1159/000139365.
The effects of DL-tetrahydropalmatine (THP; a main active substance of the Chinese herb corydalis), haloperidol (a dopamine D2 receptor antagonist), apomorphine and amphetamine on cardiovascular function and striatal dopamine (DA) release were compared in rats under general anesthesia. Intravenous administration of THP (1-10 mg/kg) or haloperidol (0.5-1.25 mg/kg) produced hypotension, bradycardia and increased DA release in the striatum. On the other hand, amphetamine (0.5-1.25 mg/kg) produced hypertension, tachycardia and increased striatal DA release. However, intravenous injection of apomorphine (0.5-1.25 mg/kg) produced hypotension, bradycardia and decreased striatal DA release. In addition, the THP-induced hypotension was attenuated by pretreatment with spinal transection or amphetamine, while the THP-induced bradycardia was attenuated by pretreatment with bilateral vagotomy or amphetamine. Thus, it appears that THP acts through DA D2 receptor antagonism to induce hypotension and bradycardia in rats.
在全身麻醉的大鼠中，比较了延胡索乙素（THP；一种中草药延胡索的主要活性物质）、氟哌啶醇（一种多巴胺D2受体拮抗剂）、阿扑吗啡和苯丙胺对心血管功能及纹状体多巴胺（DA）释放的影响。静脉注射THP（1 - 10毫克/千克）或氟哌啶醇（0.5 - 1.25毫克/千克）可导致低血压、心动过缓，并增加纹状体中DA的释放。另一方面，苯丙胺（0.5 - 1.25毫克/千克）可导致高血压、心动过速，并增加纹状体DA的释放。然而，静脉注射阿扑吗啡（0.5 - 1.25毫克/千克）可导致低血压、心动过缓，并减少纹状体DA的释放。此外，脊髓横断或苯丙胺预处理可减弱THP诱导的低血压，而双侧迷走神经切断或苯丙胺预处理可减弱THP诱导的心动过缓。因此，似乎THP通过拮抗多巴胺D2受体在大鼠中诱导低血压和心动过缓。
