Müller-Schweinitzer E
Sandoz Pharma AG, Basel, Switzerland.
Cardiovasc Drugs Ther. 1990 Dec;4(6):1455-60. doi: 10.1007/BF02026491.
Dihydroergocristine (DHEC) and dihydroergotamine (DHE) were investigated on canine saphenous veins in vivo and on canine saphenous veins and basilar arteries in vitro. Following local i.v. infusion in vivo, the venoconstrictor response to DHEC was about 30% weaker than that produced by DHE. When administered orally, however, both ergot alkaloids elicited similar venoconstrictor effects. In vitro maximal contractile responses to DHEC and DHE of basilar arteries were only 20-30% of those produced by 5-HT, whereas in saphenous veins both DHEC and DHE elicited similar maximal effects as those observed with 5-HT. In saphenous veins, methiothepin antagonized venoconstrictor responses to 5-HT, DHEC, and DHE within the same concentration range, being significantly less potent when tested against noradrenaline. The reverse was true for yohimbine, which was significantly more potent against noradrenaline than against 5-HT, DHEC, and DHE. It is suggested that the venoconstrictor responses to both DHEC and DHE are mediated through 5-HT1-like receptors.
在体研究了双氢麦角隐亭（DHEC）和双氢麦角胺（DHE）对犬隐静脉的作用，并在体外研究了它们对犬隐静脉和基底动脉的作用。在体局部静脉内输注后，DHEC引起的静脉收缩反应比DHE产生的反应弱约30%。然而，口服给药时，两种麦角生物碱引起的静脉收缩作用相似。在体外，基底动脉对DHEC和DHE的最大收缩反应仅为5-羟色胺（5-HT）产生反应的20%-30%，而在隐静脉中，DHEC和DHE引起的最大效应与5-HT观察到的相似。在隐静脉中，甲硫噻平在相同浓度范围内拮抗对5-HT、DHEC和DHE的静脉收缩反应，与去甲肾上腺素相比其效力明显较低。育亨宾的情况则相反，它对去甲肾上腺素的效力明显比对5-HT、DHEC和DHE的效力更强。提示对DHEC和DHE的静脉收缩反应均通过5-HT1样受体介导。
