Résumé
The Pentaspan is a high molecular weight(250,000), hyperosmolar(320 mOsm/l) colloid solution and blood volume expander in clinical practice. Many researches revealed the decreasing of systemic vascular resistance and pulmonary vascular resistance after Pentaspan administration in vivo. Some colloid solution is contraindicated in acute renal failure. We tried to confirm the direct effects of the Pentaspan and its mechanism on the abdominal aorta and renal artery in vitro. The rat abdominal aorta and renal artery were precontracted with norepinephrine(10(-7) M/1) in 50 ml Krebs solution and 5 ml Pentaspan was infused. Ten mininutes after, changes of the vascular tones were obtained. The results were as follows. 1) The vascular tones were significantly decreased in both vessels. 2) Abdominal aorta group, renal artery group and with or without endothelium group were not significant different each other. 3) The vascular tones were not affected by with or without endothelium, indomethacin and methylene blue pretreatment. Smooth muscles were induced relaxation by the Pentaspan infusion and the relaxation were not dependent to endothelium derived relaxing factor, prostanoid and cyclic guanosinemonophosphate.