WASHINGTON -- The heart is one of the most energy demanding organs of the human body. Its failure to function properly accounts for 600,000 deaths each year. Similarly, the rainbow trout, native to the Pacific Northwest and beloved as a sport- and food fish, requires dynamic and sustained cardiac function to maintain its health and swimming activity.

Previous studies of trout cardiac performance and energy metabolism have been conducted under hypoxic (oxygen shortage) conditions, but gender was not specifically examined. Nor were comparisons made between male and female fish (the largest group of vertebrates) made. There is a growing appreciation of significant sex differences in cardiac characteristics and function in adult humans. A new research study begins to close the gender gap in fishes, and finds that sex differences in cardiac performance and metabolism exist in rainbow trout. These differences occur at a young age and are only realized when the trout heart is contracting and not under resting conditions.

The study is entitled Sex Differences in Cardiac Glucose Metabolism and Function in Immature Rainbow Trout (Oncorhynchus mykiss). It was conducted by Pavan K. Battiprolu, Adam C. Goddard and Kenneth J. Rodnick, all of the Department of Biological Sciences, Idaho State University, Pocatello, Idaho. Dr. Rodnick's laboratory is presenting the team's findings at the 120th American Physiological Society (APS; www.the-APS.org) annual meeting, which is being held as part of the Experimental Biology (EB '07) conference. More than 12,000 scientific researchers will attend the gathering being held April 28-May 2, 2007 at the Washington, DC Convention Center.

The Study

The researchers examined if two regulatory molecules found in the fish heart -- citrate (an acid which inhibits the glycolytic metabolic pathway) and pyruvate dehydrogenase (PDH), the enzyme allowing carbohydrates t
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Contact: Donna Krupa
DKrupa@the-APS.org
301-634-7209
American Physiological Society
30-Apr-2007