Hamlyn J M
Department of Physiology, University of Maryland, Baltimore 21201.
J Endocrinol. 1989 Jul;122(1):409-20. doi: 10.1677/joe.0.1220409.
Plasma levels of an endogenous digitalis-like factor (EDLF) and atrial peptides were followed in pigs confined to metabolic cages during the development of deoxycorticosterone acetate (DOCA)-induced hypertension. During the first 2 days of DOCA treatment, urinary sodium excretion decreased and the plasma levels of renin and atrial peptide fell significantly. During this period, plasma levels of EDLF increased greater than 30-fold from a baseline of less than 0.25 to 9.72 nmol ouabain equivalents/l. Between days 2 and 5 of DOCA treatment, urinary sodium returned to pre-DOCA levels ('mineralocorticoid escape') and during this period significant increases of atrial peptide and mean arterial pressure (MAP) and a decrease in EDLF were found. Following mineralocorticoid escape there was a secondary rise in levels of EDLF and atrial peptide and both phenomena correlated with MAP (EDLF, r = 0.87, P less than 0.05; atrial peptide, r = 0.9, P less than 0.05) and with each other (r = 0.96, P less than 0.05) over a 20-day period. Acute expansion of extracellular fluid volume before DOCA elicited significant increments in plasma EDLF and atrial peptide. Volume loading during chronic DOCA treatment increased plasma EDLF significantly whereas no response of atrial peptide was detected. These results suggest that DOCA affects the reactivity of mechanisms involved in the perception of and/or response to acute changes in volume status. However, neither EDLF nor atrial peptide appear to be viable candidates as direct mediators of mineralocorticoid escape. Finally, the nature of the changes found in EDLF and atrial peptide levels during DOCA treatment suggest that these factors are involved in the long-term control of blood pressure in this model of low renin hypertension.
在醋酸脱氧皮质酮（DOCA）诱导的高血压发展过程中，对置于代谢笼中的猪体内内源性洋地黄样因子（EDLF）和心房肽的血浆水平进行了跟踪监测。在DOCA治疗的前2天，尿钠排泄减少，肾素和心房肽的血浆水平显著下降。在此期间，EDLF的血浆水平从低于0.25的基线水平增加至9.72纳摩尔哇巴因当量/升，增幅超过30倍。在DOCA治疗的第2天至第5天之间，尿钠恢复到DOCA治疗前的水平（“盐皮质激素逃逸”），在此期间发现心房肽和平均动脉压（MAP）显著升高，而EDLF降低。盐皮质激素逃逸后，EDLF和心房肽水平出现二次升高，在20天的时间里，这两种现象均与MAP相关（EDLF，r = 0.87，P < 0.05；心房肽，r = 0.9，P < 0.05），且二者之间也相关（r = 0.96，P < 0.05）。DOCA治疗前急性扩充细胞外液容量可使血浆EDLF和心房肽显著增加。慢性DOCA治疗期间进行容量负荷可使血浆EDLF显著增加，而未检测到心房肽有反应。这些结果表明，DOCA影响参与感知和/或应对容量状态急性变化的机制的反应性。然而，EDLF和心房肽似乎都不是盐皮质激素逃逸的直接介质的可行候选者。最后，DOCA治疗期间EDLF和心房肽水平变化的性质表明，这些因素参与了该低肾素性高血压模型中血压的长期控制。
