Metting P J, Levin J A, Samuels J T
J Appl Physiol (1985). 1985 Jan;58(1):244-50. doi: 10.1152/jappl.1985.58.1.244.
Isolated rat lungs, pretreated with 100 microM pargyline and 100 microM U-0521 (3',4'-dihydroxy-2-methylpropriophenone) to block metabolism of norepinephrine (NE), were perfused with 0.3 microM 3H-labeled l-norepinephrine (1-[3H]-NE) for 30 min. Efflux samples were then collected for 30 min during washout of the tissue with amine-free Krebs solution. Compartmental analysis (nonlinear least-squares regression) of the efflux of tissue l-[3H]NE content vs. time indicates that NE is accumulated in a large slowly equilibrating compartment (t 1/2 = 58.15 +/- 6.84 min) in addition to distribution in the vascular (blue dextran tracer) and extracellular ([3H]sorbitol tracer) fluid compartments of the lung. Pretreatment of the lungs with 100 microM cocaine hydrochloride reduces the total l-[3H]NE space from 7.44 +/- 1.91 to 2.48 +/- 0.23 ml/g (P less than 0.05) by selectively decreasing the size of the slow NE compartment from 6.99 +/- 1.97 to 1.67 +/- 0.14 ml/g (P less than 0.05). The large size, cocaine sensitivity, and long efflux half time of this compartment suggest that neuronal uptake contributes to the pulmonary vascular inactivation of l-[3H]NE.
用100微摩尔的帕吉林和100微摩尔的U - 0521（3'，4'-二羟基-2-甲基苯丙酮）预处理分离的大鼠肺，以阻断去甲肾上腺素（NE）的代谢，然后用0.3微摩尔的3H标记的左旋去甲肾上腺素（1-[3H]-NE）灌注30分钟。在用无胺的Krebs溶液冲洗组织的过程中，随后收集30分钟的流出样品。组织中左旋[3H]NE含量的流出量与时间的房室分析（非线性最小二乘法回归）表明，除了分布在肺的血管（蓝色葡聚糖示踪剂）和细胞外（[3H]山梨醇示踪剂）液室中，NE还积聚在一个大的缓慢平衡的房室中（t 1/2 = 58.15 +/- 6.84分钟）。用100微摩尔的盐酸可卡因预处理肺，通过选择性地将缓慢NE房室的大小从6.99 +/- 1.97毫升/克减少到1.67 +/- 0.14毫升/克（P小于0.05），使总左旋[3H]NE空间从7.44 +/- 1.91减少到2.48 +/- 0.23毫升/克（P小于0.05）。这个房室的大尺寸、可卡因敏感性和长流出半衰期表明，神经元摄取有助于肺血管中左旋[3H]NE的失活。
