Yeah, I thought the main purpose when they developed DMSA was to chelate lead?
here's something I should have posted here earlier, but I doubt this is news to Newport. The use of calcium and ascorbic acid along with DMSA.
From Here:
http://www.springerlink.com/content/82n737633756070m/
Yingjun Liao1, Jun Zhang2, Yaping Jin3 , Chunwei Lu3, Gexin Li3, Fei Yu4, Xuping Zhi4, Li An4 and Jun Yang4
(1) Department of Physiology, School of Basic Medicine, China Medical University, Shenyang, P.R. China
(2) Department of Public Health Management, School of Professional Technology, Liaoning College of Traditional Chinese Medicine, Shenyang, P.R. China
(3) Department of Environmental and Occupational Health, School of Public Health, China Medical University, No. 92 Beier Road, Heping District, Shenyang, Liaoning, 110001, P.R. China
(4) Department of Nutrition and Food Hygiene, China Medical University, Shenyang, P.R. China
Received: 4 August 2006 Accepted: 18 January 2007 Published online: 8 February 2007
Abstract The aim of this study was to explore the therapeutic efficacies of combined use of meso-2,3-dimercaptosuccinic acid (DMSA) with calcium and ascorbic acid in the treatment of mild to moderately lead-intoxicated mice. Female albino mice were exposed to lead by drinking water contaminated with 0.1% (moderate lead exposure) or 0.05% (mild lead exposure) lead acetate. After the cessation of lead exposure, mice were supplemented by gavage with saline solution, 50 mg/kg body weight (b.w) DMSA, 100 mg/kg b.w DMSA, calcium and ascorbic acid, or 50 mg/kg b.w DMSA and calcium as well as ascorbic acid, respectively. Atomic absorption spectrophotometric method was used to analyze lead levels in blood, bone, liver, kidney and brain. Activities of blood δ-aminolevulinic acid dehydratase (ALAD) were determined by colorimetric method. DMSA supplemented alone could reduce lead levels in both soft tissues and bone and reverse lead-inhibited activities of blood ALAD in mild to moderately lead-intoxicated mice. On the other hand, combined use of DMSA with calcium and ascorbic acid achieved better therapeutic efficacies in mobilizing lead in blood, liver and kidney, and reversing lead-inhibited activities of blood ALAD in moderately lead intoxicated mice than DMSA supplemented alone. Moreover, the better therapeutic efficacies were also found in mildly lead intoxicated mice in mobilizing lead in blood and bone achieved by combined use of DMSA with calcium and ascorbic acid. Combined use of DMSA with calcium and ascorbic acid seems to be the better choice in the treatment of mild to moderate lead-intoxication.
Keywords Lead intoxicated mice - Meso-2,3-dimercaptosuccinic acid (DMSA) - Calcium - Ascorbic acid - Lead body burden - δ-Aminolevulinic acid dehydratase (ALAD)
Yaping Jin
Email: jinyp@mail.cmu.edu.cn
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