Cardiovascular Effects of Hyperhomocysteinemia in Conscious Unrestrained Rats

Abstract

Experiments were designed to determine whether hyperhomocysteinemia (Hhe) affects cardiovascular function when monitored in conscious unrestrained animals. Adult, male Sprague-Dawley rats were fed a homocystine-supplemented diet for 6 months. Blood pressure (BP), heart rate, and pulse pressure were monitored continuously, 24 h a day, using biotelemetry techniques. The resulting intermediate level of Hhe was not associated with significant changes in heart rate, diastolic BP, systolic BP, or the circadian variation in heart rate. In spite of the lack of significant changes in systolic and diastolic BP, there was a slight but statistically significant increase in pulse pressure after 4 months of treatment that returned toward control levels after 6 months. Current results indicate that Hhe alone does not have significant effects on BP. Furthermore, they suggest that the previously reported Hhe-induced adverse cardiac remodeling and diastolic dysfunction in this animal model are not the result of pressure overload.