Oliver W J, Neel J V, Grekin R J, Cohen E L
Circulation. 1981 Jan;63(1):110-6. doi: 10.1161/01.cir.63.1.110.
The Yanomama Indians of northern Brazil and southern Venezuela have been identified as a "no-salt" culture. In this study, data were obtained to determine in this population the adjustments of sodium-related hormones to the stresses imposed upon sodium balance by pregnancy and prolonged lactation. Controls against the possibility that findings in the Yanomama were ethnic rather than dietary were provided by similar observations in the Guaymi Indians of Panama, who have free access to salt. Urinary concentrations of sodium were approximately 1 mEq/l in male and female Yanomama, with 24-hour excretion rates in the males averaging 1 mEq, similar to our prior observation. The pregnant Yanomama had exceeding high urinary concentrations of aldosterone. These were associated with higher plasma renin activities and serum aldosterone concentrations than in all other subjects. Although pregnant Guaymi had elevations of serum and urinary aldosterone, these were significantly lower (p < 0.001) than those of the Yanomama. Prolonged lactation in the Yanomama was associated with elevation of plasma renin activity and serum and urinary aldosterone concentration compared with the Guaymi, but were not higher than those in nonlactating Yanomama females. The findings suggest that pregnancy in a salt-poor environment is associated with an exaggerated augmentation of hormonal responses that enhance positive sodium balance.
巴西北部和委内瑞拉南部的亚诺玛米印第安人被认定为“无盐”文化群体。在本研究中,获取了相关数据,以确定该人群中与钠相关的激素对怀孕和长期哺乳给钠平衡带来的压力所做出的调节。通过对巴拿马的瓜伊米印第安人进行类似观察,排除了亚诺玛米人的研究结果是种族因素而非饮食因素导致的可能性,瓜伊米印第安人可以自由获取盐分。亚诺玛米男性和女性的尿钠浓度约为1毫当量/升,男性24小时排泄率平均为1毫当量,这与我们之前的观察结果相似。怀孕的亚诺玛米人尿醛固酮浓度极高。与所有其他受试者相比,这些浓度与更高的血浆肾素活性和血清醛固酮浓度相关。尽管怀孕的瓜伊米人血清和尿醛固酮水平有所升高,但显著低于(p < 0.001)亚诺玛米人。与瓜伊米人相比,亚诺玛米人长期哺乳与血浆肾素活性、血清和尿醛固酮浓度升高有关,但不高于未哺乳的亚诺玛米女性。研究结果表明,在缺盐环境中怀孕与激素反应的过度增强有关,这种增强会促进钠的正平衡。