Forsyth R P, Saxena P R
J Pharm Pharmacol. 1978 Aug;30(8):503-7. doi: 10.1111/j.2042-7158.1978.tb13303.x.
Systemic and regional haemodynamic variables were measured at the baseline and after saline or 5-HT infusions (5 microgram kg-1 min-1, i.v.) or methysergide injections (0.5 mg kg-1, i.v.). Cardiac output and its complete distribution were measured by the radioactive microsphere (15 micrometer diam) technique. Although 5-HT did not change the systemic variables, methysergide caused a moderate increase in systolic and mean blood pressure and heart rate. 5-HT caused a substantial increase in gastric and a moderate increase in cerebral and myocardial blood flow at the expense of that to the lungs (arteriovenous shunt + bronchial flows), kidneys and skin. While methysergide was able to reduce the vascular responses to 5-HT in stomach, skin, kidneys, heart, lungs and brain, the drug itself, like 5-HT, decreased the number of microspheres reaching the lungs. Since a large number of 15 micron microspheres can escape through the arteriovenous anastomoses to lodge in the lungs it seems likely that both 5-HT and methysergide can reduce the 'non-nutrient' flow through these anastomoses.
在基线时以及输注生理盐水或5-羟色胺（5微克/千克/分钟，静脉注射）或注射麦角新碱（0.5毫克/千克，静脉注射）后，测量全身和局部血流动力学变量。采用放射性微球（直径15微米）技术测量心输出量及其完整分布。尽管5-羟色胺未改变全身变量，但麦角新碱导致收缩压、平均血压和心率适度升高。5-羟色胺使胃血流量大幅增加，使脑和心肌血流量适度增加，代价是肺（动静脉分流+支气管血流）、肾和皮肤的血流量减少。虽然麦角新碱能够降低胃、皮肤、肾、心脏、肺和脑对5-羟色胺的血管反应，但该药物本身与5-羟色胺一样，减少了到达肺的微球数量。由于大量15微米的微球可通过动静脉吻合支逸出并滞留在肺中，因此5-羟色胺和麦角新碱似乎都能减少通过这些吻合支的“非营养性”血流。
