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目的探讨模拟失重对大鼠不同动脉血管肾上腺素受体功能的影响。方法采用尾部悬吊方法模拟失重，利用离体动脉血管环测定动脉血管肾上腺素受体介导的血管反应性的变化。结果模拟失重８周大鼠腹主动脉、肠系膜前动脉与股动脉对苯肾上腺素（１０－９ｍｏｌ／Ｌ～１０－４ｍｏｌ／Ｌ）的收缩反应均减弱，而颈总动脉对苯肾上腺素的反应无明显变化；股动脉对异丙肾上腺素（１０－９ｍｏｌ／Ｌ～１０－４ｍｏｌ／Ｌ）的舒张反应在悬吊大鼠明显减弱，而颈总动脉、腹主动脉与肠系膜前动脉对异丙肾上腺素的反应无明显改变；各动脉对苯肾上腺素与异丙肾上腺素反应的敏感性（ＥＣ５０）未发现明显变化。结论８周尾部悬吊模拟失重改变了大鼠动脉血管肾上腺素受体介导的血管反应性，结果提示此变化可能是由于平滑肌信号转导或收缩装置改变所致，而肾上腺素受体本身数量或敏感性的变化在其中所起作用有限。
Objective To investigate the effects of simulated weightlessness on adrenoreceptor function in different arterial vessels in rats. Methods The tail suspension method was used to simulate the weightlessness. Arterial vascular adrenoceptor - mediated vasoreactivity was measured by using isolated arterial rings. Results The contractile responses to phenylephrine (10-9mol / L ~ 10-4mol / L) in abdominal aorta, mesenteric artery and femoral artery in simulated 8-week-old rats were weakened, while the response of common carotid arteries to phenylephrine No significant changes; femoral artery isoproterenol (10-9mol / L ~ 10-4mol / L) diastolic response was significantly weakened in the suspension of rats, while the common carotid artery, abdominal aorta and pre-mesenteric artery to the isopia Adrenaline response did not change significantly; the arterial response to phenylephrine and isoproterenol sensitivity (EC50) found no significant change. Conclusion Simulated weightlessness of 8-week tail suspension changes the adrenergic receptor-mediated vasoreactivity of the arterial vessels in rats. The results suggest that this change may be due to changes in smooth muscle signal transduction or contractile devices, while the number of adrenergic receptors themselves Or changes in sensitivity have a limited role to play in them.