Foster Julie M, Forster Malcolm E, Olson Kenneth R
School of Biological Sciences, University of Canterbury, Private Bag 4800, Christchurch 8020, New Zealand.
Comp Biochem Physiol C Toxicol Pharmacol. 2008 Aug;148(2):107-11. doi: 10.1016/j.cbpc.2008.04.004. Epub 2008 Apr 13.
We used myography on five different arteries and three veins of the hagfish, Eptatretus cirrhatus, to test the response of vessels to vasoactive drugs. Concentration-response curves were generated for carbachol, endothelin-1, arginine vasotocin and the adrenergic agonists, phenylephrine and isoprenaline. pEC50 values indicated that veins were more sensitive to endothelin-1 than were arteries, but the arteries were more sensitive to the cholinergic agonist, carbachol. Segmental arteries did not react to arginine vasotocin, but all other vessels did, and on a molar basis it was the most potent agonist tested. That ventral and dorsal aortas were more sensitive to arginine vasotocin than smaller vessels might indicate that this neurohypophysial peptide has the potential to exert a profound influence on branchial vascular resistance and cardiac output in hagfishes. The results also demonstrate the potential for a variety of endogenous peptides to contribute to central venous tone.
我们用离体肌动描记法对盲鳗（Eptatretus cirrhatus）的五条不同动脉和三条静脉进行了研究，以测试血管对血管活性药物的反应。生成了卡巴胆碱、内皮素-1、精氨酸血管升压素以及肾上腺素能激动剂去氧肾上腺素和异丙肾上腺素的浓度-反应曲线。半数有效浓度的负对数值（pEC50）表明，静脉对内皮素-1的敏感性高于动脉，但动脉对胆碱能激动剂卡巴胆碱更为敏感。节段性动脉对精氨酸血管升压素无反应，但所有其他血管均有反应，且按摩尔计算，它是所测试的最有效的激动剂。腹主动脉和背主动脉对精氨酸血管升压素的敏感性高于较小的血管，这可能表明这种神经垂体肽有可能对盲鳗的鳃血管阻力和心输出量产生深远影响。研究结果还表明，多种内源性肽可能影响中心静脉张力。
