Péronnet F, Boudreau G, de Champlain J, Nadeau R A
Département d'éducation physique, Université de Montréal, QC, Canada.
Can J Physiol Pharmacol. 1993 Dec;71(12):884-8. doi: 10.1139/y93-134.
The effect of short-term (10 min) and prolonged (180 min) epinephrine (E) infusion (92.5 ng.kg-1.min-1) on E content of the myocardium and on the subsequent release of E from the heart during stimulation of the left stellate ganglion (4 and 10 Hz, 4 V, 2 ms, 1 min) was studied in anesthetized dogs. The E content in the free wall of the left ventricle significantly increased 1.7- and 4.2-fold following short-term and prolonged E infusion, respectively, compared with a control group infused with saline. Tissue norepinephrine (NE) content was not modified by E infusion. The plasma E concentration gradient across the heart indicated a significant release of E during electrical stimulation of the left stellate ganglion, which was related to the amount of E stored in the tissue (e.g., control, 126 +/- 60; 10-min infusion, 279 +/- 105; 180-min infusion, 1487 +/- 287 pg.mL-1; at 10 Hz). NE release from the heart also tended to increase with the amount of E stored in the myocardium and released upon electrical stimulation of the left stellate ganglion, although the difference did not reach statistical significance. These results provide further direct evidence that blood-borne E can be taken up and stored in sympathetic nerve endings and can be released as a cotransmitter with NE. Locally released E could favor NE release.
在麻醉犬中，研究了短期（10分钟）和长期（180分钟）输注肾上腺素（E）（92.5纳克·千克⁻¹·分钟⁻¹）对心肌E含量以及随后在刺激左星状神经节（4和10赫兹、4伏、2毫秒、1分钟）时心脏释放E的影响。与输注生理盐水的对照组相比，短期和长期输注E后，左心室游离壁中的E含量分别显著增加了1.7倍和4.2倍。输注E未改变组织去甲肾上腺素（NE）含量。跨心脏的血浆E浓度梯度表明，在电刺激左星状神经节期间E有显著释放，这与组织中储存的E量有关（例如，对照组为126±60；输注10分钟组为279±105；输注180分钟组为1487±287皮克·毫升⁻¹；在10赫兹时）。心脏释放的NE也倾向于随着心肌中储存并在电刺激左星状神经节时释放的E量增加而增加，尽管差异未达到统计学显著性。这些结果提供了进一步的直接证据，表明血源性E可被摄取并储存于交感神经末梢，且可作为与NE的共递质释放。局部释放的E可能有利于NE的释放。
