Characterization and quantification of myocardial collagen in the borderline hypertensive rat

Abstract

Hypertension or high blood pressure is a response to an increase in blood volume that the heart must pump at a given period of time or an increase in resistance that blood vessels must overcome to generate an adequate cardiac output, thus adequate oxygen delivery and tissue perfusion. More than 50 million Americans have hypertension; consequently it is a public health threat and a powerful independent predictor of premature death and disability from cardiovascular complications (Ayala et al., 2005). Uncontrolled hypertension can lead to an increase in existing myocyte size and left ventricular hypertrophy (LVH), which are accompanied by a detrimental collagen restructuring. Hemodynamic factors largely control ventricular myocyte hypertrophy, whereas, nonhemodynamic factors control increased synthesis and relative distribution of Collagen I and Collagen III fibers. Over time, pathological changes occur in the heart that lead to diastolic and systolic dysfunction and heart failure. This study was designed to characterize and quantitate myocardial Collagen I and III in the Borderline Hypertensive rat using polyacrylamide gel electrophoresis.

The results of these experiments demonstrated that the optimum conditions for electrophoresis were a 10 hour CNBr digestion and a 10% gel concentration. With SDS gel electrophoresis, we were able to resolve Collagen I and III using markers at a Rf value of .95 for Collagen I and .85 for Collagen III.