Volpe M, Cuocolo A, Vecchione F, Lembo G, Pignalosa S, Condorelli M, Trimarco B
Istituto di Clinica Medica, Facoltà di Medicina, Università di Napoli, Naples, Italy.
Am J Physiol. 1989 Mar;256(3 Pt 2):H852-8. doi: 10.1152/ajpheart.1989.256.3.H852.
We investigated the influence of acute volume expansion on the hemodynamic and renal responses to the constant infusion of atrial natriuretic factor (ANF) (alpha-human ANP, 2 micrograms/kg bolus, 0.2 microgram.kg-1.min-1) in rabbits anesthetized with ketamine and acepromazine. The effects of the peptide were evaluated in 12 euvolemic rabbits and in 15 rabbits during the steady-state phase of volume expansion (0.9% NaCl 4.5 ml/min for 60 min). In the euvolemic animals, ANF caused an increase in natriuresis and a reduction in blood pressure (BP), which was associated with a decrease in cardiac output (CO), stroke volume (SV), and no significant changes in central venous pressure (CVP), peripheral hematocrit (Hct), and heart rate (HR). When the peptide was infused in the volume-expanded animals, the effects of ANF on BP and HR were comparable with those observed in the euvolemic animals. However, in these animals the ANF-induced changes in CO, SV, CVP, and Hct were significantly greater than those observed in the euvolemic group. In addition, the percent increases in diuresis and natriuresis were significantly smaller than those obtained in the euvolemic animals. In conclusion, volume expansion with saline potentiates the effects of ANF on systemic hemodynamics and blood volume.
我们研究了急性容量扩张对用氯胺酮和乙酰丙嗪麻醉的家兔持续输注心房利钠因子（ANF）（α-人ANP，2微克/千克推注，0.2微克·千克⁻¹·分钟⁻¹）时血液动力学和肾脏反应的影响。在12只血容量正常的家兔和15只处于容量扩张稳态期（0.9%氯化钠4.5毫升/分钟，持续60分钟）的家兔中评估了该肽的作用。在血容量正常的动物中，ANF导致利钠增加和血压（BP）降低，这与心输出量（CO）、每搏输出量（SV）降低以及中心静脉压（CVP）、外周血细胞比容（Hct）和心率（HR）无显著变化有关。当在容量扩张的动物中输注该肽时，ANF对BP和HR的作用与在血容量正常的动物中观察到的作用相当。然而，在这些动物中，ANF诱导的CO、SV、CVP和Hct的变化明显大于在血容量正常组中观察到的变化。此外，利尿和利钠的百分比增加明显小于在血容量正常的动物中获得的增加。总之，用生理盐水进行容量扩张可增强ANF对全身血液动力学和血容量的作用。
