Recently, the American Heart Association (AHA) released a report entitled “Calcium Density of Plasma Membrane in Patients With Chronic Cardiovascular Disease: A Calcium assay for Measurement of Cardiac Function,” which is a summary of their official publication” Experimental Cardiovascular Research.” The abstract begins, “Coronary artery disease is a common and potentially modifiable cause of death. It is the second leading cause of death in the United States after cancer.” We will now examine the calcium density of plasma membrane in relation to cardiac function.
A calcium assay is a non-invasive, non-toxic, easy to perform test that can measure calcium levels in human cells. Your physician may recommend a calcium assay to help him assess your calcium levels. The calcium assay is performed with a specially designed, battery-operated, cellular probes called a “phosphorimager” or “phosphor grid.” The calcium ions are introduced into the cell culture supernatant by a small needle. The probe then measures the calcium levels.
Points From Further Findings
The abstract further states, “The calcium concentration of human cell culture supernatant is assessed using a newly developed, automated, high-performance mobile calcium probe that is composed of a silicon-based semiconductor coupled mass spectrophotometer and a lithium iodide probe.” In an accompanying article in the Journal of Clinical Investigation, the investigators reported their test results with this calcium assessment kit. The calcium profile was determined for every one hundred cells/ml. The results were compared to a control group. The calcium profile showed significantly higher levels of calcium in the new cells than in the control group.
“When the calcium uptake was measured over time, we observed a steady gain in the level of calcium in the blood stream,” the investigators concluded. This calcium uptake/release testing was performed in both normal and diseased rats. It is not clear from the abstract, how much of the test compound was actually bound to the plasma protein. It is not included in the commentary accompanying this study.
A second group reported in a JAMA Internal Medicine report (Vol. 8A) that their analysis of urinary calcium levels did not indicate a significant association between calcium intake and abnormal calcification. However, they cautioned that the test could be conducted on only a few blood groups and that more research was needed. The third group did not perform a Calcium uptake measurement. They reported, “We conclude that the relation between calcium intake and urinary calcium levels is not established by this test. More studies are needed to determine the role of calcium in health.”
Calcium bioavailability studies were performed on four types of cell: human cell lines (three), rats (two), and cells from a common laboratory strain that grows well (three). The researchers showed no significant difference in cell bioavailability when either normal or diseased cells were added. These experiments provide further evidence that calcium supplementation may not help patients with heart disease, as had been previously believed.