We have located links that may give you full text access.
Journal Article
Research Support, U.S. Gov't, P.H.S.
Demethylation of methyl mercury in different brain sites of Macaca fascicularis monkeys during long-term subclinical methyl mercury exposure.
Toxicology and Applied Pharmacology 1995 October
Total (T-Hg) and inorganic (I-Hg) mercury concentrations were determined in specific brain sites (cerebellum, occipital pole, pons, motor strip, frontal pole, temporal pole, thalamus, and pituitary) of female Macaca fascicularis monkeys exposed to daily peroral doses (50 micrograms Hg/kg body weight) of methyl mercury (MeHg) for 6, 12, or 18 months, or to continuous iv infusion of HgCl2 (200 micrograms Hg/kg body wt). In normal weight monkeys (2.4-4.1 kg body wt), the average concentration of MeHg (calculated as T-Hg minus I-Hg) was about the same in all brain sites, except the pituitary--3.0 micrograms Hg/g at 6 months, 4.2 micrograms/g at 12 months, and 4.3 micrograms Hg/g at 18 months. MeHg concentrations in the pituitary were about 50% of those in the other brain sites. In a group of monkeys that were kept unexposed for 6 months following 12 months of MeHg exposure, T 1/2 for MeHg was about 37 days in all brain sites, with the exception of the pituitary, where it was shorter. The concentration of I-Hg increased in all brain sites, but especially in the thalamus and pituitary, with the time of MeHg exposure. In most brain sites, I-Hg constituted about 9% of T-Hg at 6 and 12 months, and 12% of T-Hg at 18 months. In the pituitary, I-Hg increased from 20% of T-Hg at 6 months to 46% at 18 months. Elimination T 1/2 for I-Hg was extremely long, 230-540 days in most brain sites and considerably longer in the thalamus and pituitary. The concentration of I-Hg in the thalamus did not decrease during the clearance period (6 months), while I-Hg in the pituitary continued to increase in spite of no additional exposure. The MeHg exposed monkeys had several times higher I-Hg concentrations in the brain than monkeys exposed to HgCl2, indicating that I-Hg was formed by demethylation of MeHg in the brain, and not by brain uptake of I-Hg formed by demethylation elsewhere in the body. There were large variations in the relative concentration of I-Hg between individual monkeys, but not between brain sites (except thalamus and pituitary). Obese monkeys (5.0-6.1 kg body wt) exposed to MeHg had higher concentrations of both MeHg and I-Hg than normal weight monkeys in all brain sites, except in the pituitary.
Full text links
Related Resources
Trending Papers
The 'Ten Commandments' for the 2023 European Society of Cardiology guidelines for the management of endocarditis.European Heart Journal 2024 April 18
Challenges in Septic Shock: From New Hemodynamics to Blood Purification Therapies.Journal of Personalized Medicine 2024 Februrary 4
A Guide to the Use of Vasopressors and Inotropes for Patients in Shock.Journal of Intensive Care Medicine 2024 April 14
Prevention and treatment of ischaemic and haemorrhagic stroke in people with diabetes mellitus: a focus on glucose control and comorbidities.Diabetologia 2024 April 17
Diagnosis and Management of Cardiac Sarcoidosis: A Scientific Statement From the American Heart Association.Circulation 2024 April 19
Eosinophilic Esophagitis: Clinical Pearls for Primary Care Providers and Gastroenterologists.Mayo Clinic Proceedings 2024 April
Essential thrombocythaemia: A contemporary approach with new drugs on the horizon.British Journal of Haematology 2024 April 9
Get seemless 1-tap access through your institution/university
For the best experience, use the Read mobile app
All material on this website is protected by copyright, Copyright © 1994-2024 by WebMD LLC.
This website also contains material copyrighted by 3rd parties.
By using this service, you agree to our terms of use and privacy policy.
Your Privacy Choices
You can now claim free CME credits for this literature searchClaim now
Get seemless 1-tap access through your institution/university
For the best experience, use the Read mobile app