Wapnir R A, Moak S A, Lifshitz F, Teichberg S
J Lab Clin Med. 1979 Jul;94(1):144-51.
When lead acetate was administered intraperitoneally to young rats at a dose of 20 mg/kg (five times a week for 6 weeks), their growth rate was retarded when compared with controls injected with sodium acetate. Only a small amount of the heavy metal reached the circulation and exerted limited effects on typical target organs. However, large, electron-dense inclusion bodies were found in the abdominal cavity. The in vivo intestinal absorption of glucose was reduced. When perfused at 40 mM concentration, the experimental animals had a mean absorption rate of 152.1 nmol/min . cm vs. 230.6 in the controls (p less than 0.01). Also, sodium and potassium transport was reduced. No effects were observed on amino acid transport and (Na+-K+)-ATPase. Mg++-ATPase, glucose-6-phosphatase, fructose-1, 6-diphosphatase, pyruvate kinase, succinic dehydrogenase, and tryptophan hydroxylase in the small intestinal mucosa and the kidney were unaltered. Renal alkaline phosphatase was decreased. These studies confirm the greater susceptibility of some active transport mechanisms of the small intestinal mucosa to lead toxicity, compared to those of the kidney.
当以20毫克/千克的剂量给幼鼠腹腔注射醋酸铅(每周5次,共6周)时,与注射醋酸钠的对照组相比,它们的生长速度减缓。只有少量重金属进入循环系统,并对典型靶器官产生有限影响。然而,在腹腔中发现了大量电子致密包涵体。体内葡萄糖的肠道吸收减少。当以40毫摩尔浓度灌注时,实验动物的平均吸收速率为152.1纳摩尔/分钟·厘米,而对照组为230.6纳摩尔/分钟·厘米(p小于0.01)。此外,钠和钾的转运也减少。未观察到对氨基酸转运和(钠 - 钾)-ATP酶的影响。小肠黏膜和肾脏中的镁离子 - ATP酶、葡萄糖 - 6 - 磷酸酶、果糖 - 1,6 - 二磷酸酶、丙酮酸激酶、琥珀酸脱氢酶和色氨酸羟化酶未发生改变。肾碱性磷酸酶降低。这些研究证实,与肾脏相比,小肠黏膜的某些主动转运机制对铅毒性更敏感。