Edwards R M, Trizna W, Feuerstein G
Department of Pharmacology, SmithKline Beecham Pharmaceuticals, King of Prussia, PA 19406-0939.
J Lipid Mediat. 1991 Mar-Apr;3(2):161-5.
We examined the effect of platelet activating-factor (PAF) on lumen diameter of penetrating intracerebral arterioles (diameter less than 50 microns) dissected from rat brains. PAF over a concentration range of 10(-12)-10(-6) M had no effect on lumen diameter. However, the arterioles were capable of both vasodilation in response to calcitonin gene-related peptide (EC50 = 4.4 nM) and vasoconstriction in response to the thromboxane mimetic, U44619 (EC50 = 5.8 nM). We conclude that the effects of PAF on the cortical circulation observed in vivo are indirect and may be due to PAF-induced changes in other humoral or cellular mediators.
我们研究了血小板活化因子（PAF）对从大鼠脑中分离出的脑内穿通小动脉（直径小于50微米）管腔直径的影响。浓度范围为10^(-12)-10^(-6) M的PAF对管腔直径没有影响。然而，这些小动脉能够对降钙素基因相关肽产生舒张反应（半数有效浓度[EC50]=4.4 nM），并对血栓素类似物U44619产生收缩反应（EC50=5.8 nM）。我们得出结论，体内观察到的PAF对皮质循环的影响是间接的，可能是由于PAF诱导其他体液或细胞介质发生变化所致。
