Lorenz R R, Vanhoutte P M
Am J Physiol. 1985 Sep;249(3 Pt 2):H685-9. doi: 10.1152/ajpheart.1985.249.3.H685.
Experiments were performed to determine the effect of aggregating platelets on adrenergic neurotransmission. Rings of canine saphenous veins and left circumflex coronary arteries were incubated with [3H]norepinephrine and suspended for superfusion. Aggregating platelets and exogenous 5-hydroxytryptamine decreased the overflow of [3H]norepinephrine evoked by electrical stimulation of the adrenergic nerve endings. The reduction of transmitter overflow caused by 5-hydroxytryptamine was prevented by the serotonergic antagonist methiothepin in a concentration that did not significantly affect the release of 5-hydroxytryptamine or thromboxane B2 from the aggregating platelets. Methiothepin decreased but did not abolish the inhibitory effect of aggregating platelets on neurotransmitter overflow. These experiments demonstrate that 5-hydroxytryptamine and other substances released from aggregating platelets can exert prejunctional inhibition of adrenergic neurotransmission in isolated blood vessels.
进行实验以确定聚集的血小板对肾上腺素能神经传递的影响。将犬隐静脉环和左旋冠状动脉环与[3H]去甲肾上腺素一起孵育，然后悬浮以进行灌流。聚集的血小板和外源性5-羟色胺减少了肾上腺素能神经末梢电刺激诱发的[3H]去甲肾上腺素溢出。5-羟色胺引起的递质溢出减少被血清素能拮抗剂甲硫噻平以不显著影响聚集血小板释放5-羟色胺或血栓素B2的浓度所阻止。甲硫噻平降低但并未消除聚集血小板对神经递质溢出的抑制作用。这些实验表明，5-羟色胺和聚集血小板释放的其他物质可在离体血管中对肾上腺素能神经传递发挥节前抑制作用。
