Cardiovascular Hypertrophy Does not Predispose to Genetic Hypertension

Abstract

It has been proposed that cardiovascular hypertrophy precedes and contributes to the development of genetic hypertension. In a genetically segregating population we determined whether susceptibility to high blood pressure was associated with cardiovascular structural abnormalities in youth In 9-week old male F2 rats derived from a cross of spontaneously hypertensive rats (SHR) and inbred normotensive Donryu (DRY) rats we determined left ventricular mass (LVM) by echocardiography and the media-lumen ratio (MLR) of mesenteric resistance vessels by biopsy. Direct mean arterial pressure was measured in the same rats at 20 weeks of age. The ranges of LVM and MLR in young F2 rats encompassed values seen SHR and DRY at this age. However, no correlation was observed between LVM or MLR and subsequent blood pressures at 20 weeks of age. The blood pressure of F2 rats with cardiovascular structural phenotypes within the SHR range was no higher than the remainder of the F2 population. These studies do not support the hypothesis that hypertrophy of the heart or mesenteric resistance vessels confer susceptibility to the development of genetic hypertension.

Key Words:

• Blood Pressure
• Blood Vessels
• Heart
• Genetics
• Susceptibility
• SHR