Testing the calcium hypothesis of aging in the rat hippocampus in vivo using manganese-enhanced MRI

Bissig, David, and Bruce A. Berkowitz. "Testing the calcium hypothesis of aging in the rat hippocampus in vivo using manganese-enhanced MRI." Neurobiology of aging 35 (2014) 1453-1458 This study used MeMRI to examine how aging affects changes in L-type calcium channels in the hippocampus. It has been hypothesized that increases in calcium influx through L-type calcium in the hippocampus that is associated with cognitive decreases. By utilizing MeMRI Dr. Berkowitz was able to non-invasively characterize L-type calcium channels in a longitudinal study. They found that aged rats have significantly increased manganese uptake in pyramidal neurons in the hippocampus compared to their younger selves. Although they were not able to look at mechanistic changes, the trends that they seen in increases in manganese uptake are consistent with the hypothesis of hippocampal plasticity linked to cognitive decline. In relation to our study this paper talks about imaging control rats as well. They found that their were no differences in the older control rats regions of interest when compared to the younger rats regions of interest. They also looked at differences in manganese uptake in animals that had been previously injected versus non-injected animals. There were no differences in animals that had been previously injected versus not injected. In the discussion they briefly talked about changes in the BBB with age that may affect manganese uptake over time. This is important to what we study since we are doing longitudinal studies. ~JI