Oikari A O, Rankin J C
J Exp Biol. 1985 Jul;117:319-33. doi: 10.1242/jeb.117.1.319.
Infusion of magnesium salts into the body cavity of freshwater-adapted rainbow trout led to elevated plasma magnesium concentrations and to stimulation of renal tubular secretion of magnesium. The majority of the infused load was excreted renally, no net branchial excretion being detected. Magnesium sulphate infusion led to increased tubular secretion of sulphate. Magnesium chloride infusion led to reduced tubular reabsorption of chloride. Magnesium could either be reabsorbed or secreted in control freshwater-adapted trout, apparently as a function of nutritional status. Fish could switch from reabsorption to secretion in response to magnesium loading. It is suggested that freshwater fish eliminate excess dietary magnesium renally.
向适应淡水环境的虹鳟鱼体腔注入镁盐会导致血浆镁浓度升高，并刺激肾小管对镁的分泌。注入的大部分镁负荷通过肾脏排出，未检测到鳃的净排泄。注入硫酸镁会导致肾小管对硫酸盐的分泌增加。注入氯化镁会导致肾小管对氯离子的重吸收减少。在对照的适应淡水环境的鳟鱼中，镁既可以被重吸收也可以被分泌，这显然取决于营养状况。鱼类可以根据镁负荷从镁的重吸收转变为分泌。研究表明，淡水鱼通过肾脏消除过量的膳食镁。
