Shalom likes to play on his computer, particularly using 3D modeling. He would like to become a software designer someday because, he says, "I like designing things and also enjoy working with computers."
While learning about the components of cells in class, Shalom learned mitochondria produce ATP, the energy source for a cell. Exercise increases the number of mitochondria in skeletal muscle cells, but it was unclear whether heart muscle cells reacted in the same way to an increased workload. Shalom hypothesized that heart muscle cells would increase their number of mitochondria in response to energy demands.
Shalom used a mouse atrial tumor cell line capable of contracting. He tested three types of such heart cells—some that were not contracting, some that were contracting slowly, or some that were electrically paced to contract rapidly. He incubated batches of cells separately for 18 hours and then stained the cells with a dye that allowed him to measure mitochondrial amounts. He also assessed mitochondria in these kinds of cells in normal-oxygen and low-oxygen environments. Shalom found that in normal-oxygen conditions, the noncontracting cells had the most mitochondria, followed in order by the electrically paced cells and the cells contracting normally. The noncontracting cells had high-energy demands because they were growing. Cells in low oxygen had fewer mitochondria.
