MULLER-Schweinitzer E, Brundell J
Eur J Pharmacol. 1975 Nov;34(1):197-206. doi: 10.1016/0014-2999(75)90240-x.
Changes in tension were monitored isometrically on spiral strips from canine saphenous veins and arteries. Dihydroergotamine (DHE) (1.7 X 10(-8) M) contracted vein strips about 30% more strongly than arterial strips when the effects were compared to a standard noradrenaline (NA) response. Phentolamine (3.6 X 10(-6) M) reduced the DHE-induced contraction in veins by about 30% and in arteries by about 10%. Indomethacin (2.8 X 10(-7) M) reduced DHE-induced contractions in veins by about 60% but enhanced the DHE effects in the arteries. When arachidonic acid (AA) was added to stimulated vascular strips it caused further contractions in veins but relaxation in arteries. Both effects were inhibited after indomethacin. In veins AA was significantly more effective in the presence of DHE as compared to controls, to NA- or to KCl-stimulated strips. In arteries AA showed the strongest relaxant activity in the presence of NA. Low doses of prostaglandin E2, however, relaxed both venous and arterial strips. The results suggest that contraction of canine vascular smooth muscle is associated with synthesis of a prostaglandin-like substance of substances having constrictor activity in veins but relaxant activity in arteries and that in venous smooth muscle cells the formation of this material is enhanced by dihydroergotamine.
采用等长方式监测犬隐静脉和动脉螺旋条带的张力变化。与标准去甲肾上腺素（NA）反应相比，双氢麦角胺（DHE）（1.7×10⁻⁸ M）使静脉条带的收缩强度比动脉条带强约30%。酚妥拉明（3.6×10⁻⁶ M）使DHE诱导的静脉收缩减少约30%，使动脉收缩减少约10%。吲哚美辛（2.8×10⁻⁷ M）使DHE诱导的静脉收缩减少约60%，但增强了DHE对动脉的作用。当向受刺激的血管条带中加入花生四烯酸（AA）时，它会使静脉进一步收缩，但使动脉舒张。两种作用在吲哚美辛处理后均受到抑制。在静脉中，与对照组、NA或KCl刺激的条带相比，在DHE存在下AA的作用显著更强。在动脉中，AA在NA存在时表现出最强的舒张活性。然而，低剂量的前列腺素E2使静脉和动脉条带均舒张。结果表明，犬血管平滑肌的收缩与一种类前列腺素物质的合成有关，该物质在静脉中具有收缩活性，在动脉中具有舒张活性，并且在静脉平滑肌细胞中，双氢麦角胺可增强这种物质的形成。
