Canadian researchers say the prescription drug, Viagra, is as good for the heart as it is for the love life.  Seems the way the drug influences the platelets in the bloodstream also minimizes the risk of heart attack and stroke.

In addition to its most well-known application as a treatment for erectile dysfunction, Viagra is also prescribed for the treatment of pulmonary hypertension.  Now, however, Donald Maurice, professor of pharmacology and toxicology at Queen’s University, Kingston, Ontario, has discovered an enzyme in the drug which targets platelet activity, too, and suggests it does so in a way that may prevent massive and sudden heart attacks or strokes in people who’ve had arterial stents implanted.

Platelets are a natural part of the blood’s system of clotting.  They cling together to stop the flow of blood at the site of injury so a small wound doesn’t become life threatening.  When stents are implanted, platelets have a tendency to cling to the stents and can eventually form a complete blockage of the stented artery.  When this happens, deadly heart attacks and strokes can occur with little or no warning.

Each cell has two different clusters of an enzyme identified as phosphodiesterase type 5 (PDE5) although only one cluster affects platelet function.  Viagra inhibits the production of PDE5 but figuring out how to manipulate that enzymatic production has remained elusive, until the Queen’s researchers made the breakthrough discovery that only one cluster of PDE5 in each cell affects platelet activity.

With better understanding of cell function in relation to the PDE5 enzyme, the research team expects to develop a way to manipulate just one cluster of PDE5 while leaving the other cluster intact.  Viagra and similar drugs that inhibit PDE5 are at the forefront of future studies of this nature.

Findings from this study are available online at the website of the international journal, Proceedings of the National Academy of Sciences.  The Canadian Institutes of Health Research and the Ontario Heart and Stroke Foundation provided funding for the study.

Source: Queen’s University