Bennett T, Mahajan R P, March J E, Kemp P A, Gardiner S M
Centre for Integrated Systems Biology and Medicine, School of Biomedical Sciences, University of Nottingham, Queen's Medical Centre, Nottingham NG7 2UH, UK.
Br J Anaesth. 2004 Sep;93(3):400-7. doi: 10.1093/bja/aeh214. Epub 2004 Jun 25.
Reduced pressor responsiveness to norepinephrine (NE) in sepsis is well documented but the associated regional haemodynamic changes are less well characterized, and there are varying reports of changes in haemodynamic responses to arginine vasopressin (AVP). We compared changes in regional haemodynamic responsiveness to AVP and NE during a 24 h continuous infusion of lipopolysaccharide (LPS) in conscious rats.
Conscious, male Sprague-Dawley rats were infused with saline (0.4 ml h(-1)) or LPS (150 micro g kg(-1) h(-1)). Renal, mesenteric, and hindquarter haemodynamic responses to 3 min infusions of AVP (0.25, 0.625, and 1.25 ng kg(-1) min(-1)) or NE (75, 250, and 750 ng kg(-1) min(-1)) were assessed 2, 6, and 24 h after the onset of LPS or saline.
Two and six hours after the onset of LPS, all haemodynamic effects of NE were markedly reduced, but by 24 h, there was some recovery in the vasoconstrictor actions of NE although the pressor and bradycardic effects were still depressed. Two hours after the onset of LPS, the cardiovascular effects of AVP were depressed but there was some recovery in vascular responsiveness at 6 h. By 24 h, only the mesenteric vasoconstrictor effect of AVP was consistently reduced.
During low dose LPS infusion, there are differential changes in haemodynamic responsiveness to AVP and NE, which show different temporal and regional profiles of recovery with time. Furthermore, reduced pressor responsiveness to NE is not necessarily accompanied by a reduced capacity of vessels for vasoconstriction.
脓毒症时去甲肾上腺素（NE）的升压反应性降低已得到充分证实，但相关的局部血流动力学变化特征尚不明确，而且关于精氨酸加压素（AVP）血流动力学反应变化的报道也各不相同。我们比较了清醒大鼠在连续24小时输注脂多糖（LPS）期间对AVP和NE的局部血流动力学反应性变化。
给清醒的雄性Sprague-Dawley大鼠输注生理盐水（0.4 ml h⁻¹）或LPS（150 μg kg⁻¹ h⁻¹）。在开始输注LPS或生理盐水后2、6和24小时，评估对3分钟输注AVP（0.25、0.625和1.25 ng kg⁻¹ min⁻¹）或NE（75、250和750 ng kg⁻¹ min⁻¹）的肾、肠系膜和后肢血流动力学反应。
LPS输注开始后2小时和6小时，NE的所有血流动力学效应均显著降低，但到24小时时，NE的血管收缩作用有所恢复，尽管升压和心动过缓效应仍受到抑制。LPS输注开始后2小时，AVP的心血管效应受到抑制，但在6小时时血管反应性有所恢复。到24小时时，只有AVP的肠系膜血管收缩效应持续降低。
在低剂量LPS输注期间，对AVP和NE的血流动力学反应性存在差异变化，随时间显示出不同的恢复时间和局部特征。此外，对NE的升压反应性降低不一定伴随着血管收缩能力的降低。
