Evaluation of manganese uptake and toxicity in mouse brain during continuous MnCl2 administration using osmotic pumps.

Contrast Media Mol Imaging. 2012 Jul-Aug;7(4):426-34. doi: 10.1002/cmmi.1469. Sepúlveda MR, Dresselaers T, Vangheluwe P, Everaerts W, Himmelreich U, Mata AM, Wuytack F. Following up on my post from last week, where a group compared injections of manganese with slow infusion via osmotic minipump, this paper is from a group that looked at the levels of manganese uptake between different brain regions following implantation of a minipump. Here, they implanted the pumps subcutaneously under the back skin of mice, to deliver 30mg/kg/day,and looked at T1 relaxation times (signal increase) after 3 weeks and found significant reductions in a number of regions. They also implanted the pumps for 12 days, before removing them and looking for changes in signal before and after removal, finding that some recovery can be seen in as little as 3 days. Interestingly, they found that tissues high in the SPCA1 Mn/Ca ATP-ase seemed to be the same areas which had higher Mn accumulation, suggesting that this pump may be responsible for sequestering Mn in the golgi apparatus. A couple of drawbacks that they saw after using minipumps were that mice treated for 3 weeks showed small but significant changes in their step sizes, as well as behavioral changes which suggested neurological damage may have occurred. -DH