Genetic Hypertension: The Okamoto Strain of Rats

Abstract

The Okamoto strain of spontaneously hypertensive rats was created in Japan in the early 1960’s and since that time it has become the most widely studied experimental model in hypertension research. A resemblance to human essential hypertension has been noted in that blood pressure increases gradually with time in both the Okamoto rat and the subject with essential hypertension, and the cause of the pressure increase remains unknown in both cases. Of the many experimental observations available for analysis, the following three may be the most relevant. Sympathetic nervous activity is significantly increased in these rats. Renal denervation has been shown to prevent hypertension as long as the denervation remains effective. When the kidneys are cross-transplanted between hypertensive animals and normotensive controls, the ultimate level of pressure is determined by the donor kidney rather than the recipient animal.