Taha S A, Raza M, El-Khawad I E
Department of Pharmacology, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia.
J Ethnopharmacol. 1998 Feb;60(1):19-26. doi: 10.1016/s0378-8741(97)00126-8.
The pharmacological effects of ambrein (isolated from ambergris) on the contractile responses induced by some agonists in smooth muscle preparations were investigated. Ambrein in the concentration range of 10, 50 and 250 microg/ml decreased the spontaneous contraction of the isolated rabbit jejunum, rat uterus and guinea-pig vas deferens. Ambrein-induced antagonism to acetylcholine (Ach) in the guinea-pig ileum was abolished when the concentration of calcium chloride in the Tyrode's solution was increased to 5 mM/l. Furthermore, ambrein did not antagonise nicotine-induced contractions in the isolated rabbit jejunum or serotonin-induced contractions in the isolated guinea-pig ileum and vas deferens or the rat uterus. However, ambrein in the concentration range of 10, 50 and 250 microg/ml antagonised prostaglandins (PGs) E2, D2, F2alpha, and oxytocin-induced contractions in the rat uterus in vitro. Ambrein also antagonised (+/-) noradrenaline and (-) adrenaline-induced contractions in the isolated guinea-pig vas deferens. It is concluded that ambrein-induced non-selective dose-dependent antagonism to the effects of some agonists (Ach, adrenaline, noradrenaline, PGs and oxytocin) in some smooth muscles may be due to the ability of this compound to interfere with the mobilisation of extracellular Ca2+ required for muscular contractions induced by these agonists.
研究了龙涎香醇（从龙涎香中分离得到）对平滑肌制剂中某些激动剂诱导的收缩反应的药理作用。浓度为10、50和250微克/毫升的龙涎香醇可降低离体兔空肠、大鼠子宫和豚鼠输精管的自发收缩。当台氏液中氯化钙浓度增加到5毫摩尔/升时，龙涎香醇对豚鼠回肠中乙酰胆碱（Ach）的诱导拮抗作用消失。此外，龙涎香醇对离体兔空肠中尼古丁诱导的收缩、离体豚鼠回肠和输精管或大鼠子宫中5-羟色胺诱导的收缩均无拮抗作用。然而，浓度为10、50和250微克/毫升的龙涎香醇在体外可拮抗前列腺素（PGs）E2、D2、F2α以及催产素诱导的大鼠子宫收缩。龙涎香醇还可拮抗离体豚鼠输精管中（±）去甲肾上腺素和（-）肾上腺素诱导的收缩。得出的结论是，龙涎香醇对某些平滑肌中某些激动剂（Ach、肾上腺素、去甲肾上腺素、PGs和催产素）的作用产生非选择性剂量依赖性拮抗作用，可能是由于该化合物能够干扰这些激动剂诱导肌肉收缩所需的细胞外Ca2+的动员。
