Hornick C A, Sanders L I, Lin Y C
Res Commun Chem Pathol Pharmacol. 1978 Nov;22(2):277-89.
Carpaine is one of the major components of alkaloid of papaya leaves. Circulatory effects of carpaine were studied in Wistar male rats weighing 314 +/- 13 g, under pentabarbital (30 mg/kg) anesthesia. Increasing dosages of carpaine from 0.5 mg/kg to 2.0 mg/kg resulted in progressive decrease in systolic, diastolic, and mean arterial blood pressure. Selective autonomic nervous blockade with atropine sulfate (1 mg/kg) or propranolol hydrochloride (8 mg/kg) did not alter the circulatory response to carpaine. Carpaine, 2 mg/kg, reduced cardiac output, stroke volume, stroke work, and cardiac power, but the calculated total peripheral resistance remained unchanged. It is concluded from these results that carpaine affects the myocardium directly. The effects of carpaine may be related to its macrocyclic dilactone structure, a possible cation chelating structure.
番木瓜碱是番木瓜叶生物碱的主要成分之一。在戊巴比妥（30毫克/千克）麻醉下，对体重为314±13克的雄性Wistar大鼠研究了番木瓜碱的循环效应。番木瓜碱剂量从0.5毫克/千克增加到2.0毫克/千克，导致收缩压、舒张压和平均动脉血压逐渐下降。用硫酸阿托品（1毫克/千克）或盐酸普萘洛尔（8毫克/千克）进行选择性自主神经阻滞，并未改变对番木瓜碱的循环反应。2毫克/千克的番木瓜碱降低了心输出量、每搏输出量、每搏功和心脏功率，但计算得出的总外周阻力保持不变。从这些结果得出结论，番木瓜碱直接影响心肌。番木瓜碱的作用可能与其大环双内酯结构有关，这是一种可能的阳离子螯合结构。
