Anat Cell Biol.  2013 Dec;46(4):239-245. 10.5115/acb.2013.46.4.239.

Vitamin C modulates lead excretion in rats

• Lihm H
• Kim H
• Chang H
• Yoon M
• Lee K
• Choi J

• KMID: 2046764
• DOI: http://doi.org/10.5115/acb.2013.46.4.239

Abstract

Lead, one of the most toxic heavy metals, takes longer time to be excreted from the body than other heavy metals. The purpose of this study is, by measuring lead excretion via urine and feces, to find out the effect of vitamin C in lead chelation. Thirty-six rats were randomly assorted into four groups. All 33 rats except for the control group were administered with lead, before orally administered with different doses of vitamin C per kilogram of body weight. The lead excretion levels in urine and feces as well as the survival rate were then measured for each group. The rats with lead administrations (10/13, 76.9%) with lead administrations only, 10/11 rats (90.9%) with lead administrations and low dose of vitamin C, 9/9 rats (100%) with lead administrations and high dose of vitamin C survived. Among the 29 surviving rats, low vitamin C intake group exhibited higher urinary excretion than the lead only group. The urinary excretion level in high dose vitamin C intakegroup was significantly higher than the lead only group. In addition, fecal lead excretion seemed to be increased in the high dose vitamin C intake group, compared to the group with lead administrations only with statistical significance. Through animal experiment, it was found out that administrating high dose of vitamin C accelerated the excretion of lead in body compared to low dose of vitamin C.

Keyword

Lead; Vitamin C; Chelation; Excretion

MeSH Terms

Animal Experimentation
Animals
Ascorbic Acid*
Body Weight
Feces
Metals, Heavy
Rats*
Survival Rate
Vitamins*
Ascorbic Acid
Metals, Heavy
Vitamins

Figure

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  Fig. 1 Experimental schedule of vitamin C (Vit. C) and lead administration and of retrieving lead from urine and feces. To measure the excretion of lead through urine and feces, urine and feces were collected on alternate days (the day before, 2nd day, 4th day, 6th day, and 8th day). To see the effect of Vit. C on suppressing intestinal absorption of lead, Vit. C was started to administrate a day before lead administration.

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  Fig. 2 Experimental flow. Overall 32 rats were included in experiment; 3 rats died in a group of lead only; 1 rat died in a group of lead and low dose vitamin C.

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  Fig. 3 Lead excretion in urine. In high dose vitamin C group, urinary lead excretion started to increase at the beginning and drastically increased through 4th and 6th day. At 8th day, excretion was still high. However in low dose vitamin C group, it did increase lead excretion, but we could clearly see the difference with high dose vitamin C group.

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  Fig. 4 Lead excretion in stool. The decrease of excretion on the 6th and 8th day appears to have relevance to the fact that a large amount of lead accumulated inside the body has already been excreted and only small amount of it remained inside the body, vitamin C groups excreted more lead than the amount of lead that was administered on the same date. On the 4th day, the lead only group excreted more lead than the amount administered on the same date, however, less than the daily administration afterwards. In other words, the decrease in the excretion of lead in the lead only group from the 6th day appears to be influenced by the limit of rat's own capacity to excrete lead unlike that in vitamin C groups, and it suggests that the accumulation of lead will grow seriously eventually.

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