Velasco I T, Baena R C, Rocha e Silva M, Loureiro M I
Divisão de Experimentação, Faculdade de Medicina, Universidade de São Paulo, Brazil.
Am J Physiol. 1990 Dec;259(6 Pt 2):H1752-8. doi: 10.1152/ajpheart.1990.259.6.H1752.
Single injections of 4 ml/kg hypertonic NaCl (7.5%) resuscitate dogs from severe blood loss (40-45 ml/kg). Mechanisms involve osmolarity-dependent volume expansion, increased myocardial contractility, and vasodilation. The role of central angiotensinergic pathways in the hemorrhage-hypertonic resuscitation interaction was investigated through experiments performed on male pentobarbital sodium-anesthetized dogs bled to, and held at, 40 mmHg for 30 min. Dogs were treated with 4 ml/kg of 7.5% NaCl or 32 of 0.9% NaCl iv preceded by intracerebroventricular (ICV) injections of 150 micrograms saralasin, 20 micrograms arginine vasopressin inhibitor (AVPI), or 10 micrograms morphine. ICV saralasin and morphine inhibited the full recovery response to hypertonic NaCl, whereas AVPI had no such effect. Saralasin did not inhibit the recovery from hemorrhagic shock produced by large volume isotonic saline reexpansion. These data demonstrate an interaction between the central angiotensin system and small volume hypertonic resuscitation from severe hemorrhagic shock but not between this central system and large volume isotonic reexpansion of circulatory volume. In contrast, the central vasopressinergic system does not appear to be similarly involved.
单次注射4毫升/千克的高渗氯化钠（7.5%）可使严重失血（40 - 45毫升/千克）的犬复苏。其机制包括渗透压依赖性的容量扩张、心肌收缩力增强和血管舒张。通过对戊巴比妥钠麻醉的雄性犬进行实验来研究中枢血管紧张素能途径在出血 - 高渗复苏相互作用中的作用，这些犬被放血至平均动脉压为40 mmHg并维持30分钟。犬静脉注射4毫升/千克的7.5%氯化钠或32毫升的0.9%氯化钠之前，先进行脑室内（ICV）注射150微克沙拉新、20微克精氨酸血管加压素抑制剂（AVPI）或10微克吗啡。脑室内注射沙拉新和吗啡可抑制对高渗氯化钠的完全恢复反应，而AVPI则无此作用。沙拉新并不抑制大量等渗盐水再灌注所导致的失血性休克的恢复。这些数据表明，中枢血管紧张素系统与严重失血性休克的小容量高渗复苏之间存在相互作用，但该中枢系统与循环容量的大量等渗再灌注之间不存在相互作用。相比之下，中枢血管加压素能系统似乎未参与其中。
