Department of Basic Medical Sciences (Physiology Section), The University of the West Indies, Mona, Kingston 7, Jamaica.
Pharm Biol. 2012 Nov;50(11):1436-41. doi: 10.3109/13880209.2012.684690. Epub 2012 Sep 11.
Annona muricata Linn (Annonaceae) (soursop) is a food plant reported to have antihypertensive properties.
We investigated the blood pressure reducing effect of its aqueous leaf extract and the possible mechanisms that may be responsible.
Intravenous administration of an aqueous leaf extract (9.17-48.5 mg/kg) of A. muricata on the mean arterial pressure and heart rate were recorded invasively on anaesthetized, normotensive Sprague-Dawley rats. Contractile responses of rat aortic rings to the extract (0.5-4.0 mg/mL) were studied using standard organ bath techniques.
A. muricata (9.17-48.5 mg/kg) caused significant (p < 0.05) dose-dependent reduction in blood pressure without affecting the heart rates. The hypotensive effects were unaffected by atropine (2 mg/kg), mepyramine (5 mg/kg), propranolol (1 mg/kg) and L-NAME (5 mg/kg). A. muricata leaf aqueous extract significantly (p < 0.05) relaxed phenylephrine (10(-9)-10(-4) M) and 80 mM KCl induced contractions in endothelium intact and denuded aortic rings; and caused a significant (p < 0.05) rightward shift of the Ca(2+) dose response curves in Ca(2+)-free Kreb's solution containing 0.1 mM EGTA.
The hypotensive effects of A. muricata are not mediated through muscarinic, histaminergic, adrenergic and nitric oxide pathways, but through peripheral mechanisms involving antagonism of Ca(2+).
安农西亚（Annonaceae）（刺果番荔枝）是一种被报道具有降血压特性的食用植物。
我们研究了其叶水提物的降压作用及其可能的作用机制。
通过静脉内给予安农西亚叶水提物（9.17-48.5mg/kg），在麻醉、正常血压的 Sprague-Dawley 大鼠上记录平均动脉压和心率。使用标准器官浴技术研究了提取物（0.5-4.0mg/mL）对大鼠主动脉环的收缩反应。
安农西亚（9.17-48.5mg/kg）引起了显著的（p < 0.05）剂量依赖性血压降低，而不影响心率。这种降压作用不受阿托品（2mg/kg）、甲哌氯丙嗪（5mg/kg）、普萘洛尔（1mg/kg）和 L-NAME（5mg/kg）的影响。安农西亚叶水提物显著地（p < 0.05）松弛了内皮完整和去内皮的主动脉环中由苯肾上腺素（10-9-10-4M）和 80mM KCl 引起的收缩，并且在含有 0.1mM EGTA 的无 Ca2+Kreb's 溶液中，使 Ca2+剂量反应曲线发生显著的（p < 0.05）右移。
安农西亚的降压作用不是通过毒蕈碱、组胺能、肾上腺素能和一氧化氮途径介导的，而是通过涉及 Ca2+拮抗的外周机制。
