Grundemar L, Wahlestedt C, Shen G H, Zukowska-Grojec Z, Håkanson R
Department of Pharmacology, University of Lund, Sweden.
Eur J Pharmacol. 1990 Apr 10;179(1-2):83-7. doi: 10.1016/0014-2999(90)90404-t.
The effects of neuropeptide Y (NPY) on systemic arterial blood pressure and heart rate were studied in anesthetized intact and pithed rats. I.v. doses of NPY (0.3-30 nmol/kg) raised the mean arterial blood pressure dose dependently. At doses of greater than or equal to 3.0 nmol/kg, the initial pressor response was followed by a dose-dependent fall in blood pressure in intact and pithed rats. The depressor response was accompanied 1-2 min after the NPY injection by a slight increase in heart rate in pithed rats but not in intact rats, and 10 min after the injection by a decrease in heart rate in intact rats. After repeated injections of NPY, the depressor effect vanished, whereas the integrated pressor response over time was markedly enhanced. After pretreatment with the histamine H1-receptor antagonist, mepyramine, or with the histamine liberator, compound 48/80, the pressor response to NPY remained but the depressor response disappeared. We suggest that the marked fall in blood pressure can be attributed to NPY-evoked histamine release from mast cells.
在麻醉的完整大鼠和去脑大鼠中研究了神经肽Y（NPY）对全身动脉血压和心率的影响。静脉注射剂量为0.3 - 30 nmol/kg的NPY可使平均动脉血压呈剂量依赖性升高。在剂量大于或等于3.0 nmol/kg时，完整大鼠和去脑大鼠在最初的升压反应后均出现血压的剂量依赖性下降。在NPY注射后1 - 2分钟，去脑大鼠的心率略有增加，但完整大鼠未出现，而在注射后10分钟，完整大鼠的心率下降。重复注射NPY后，降压作用消失，而随着时间推移的累积升压反应明显增强。在用组胺H1受体拮抗剂美吡拉敏或组胺释放剂48/80预处理后，对NPY的升压反应仍然存在，但降压反应消失。我们认为，血压的显著下降可归因于NPY引起的肥大细胞组胺释放。
