Rb86 uptake of various organs of the spontaneously hypertensive rats: (a preliminary note)

Twenty spontaneously hypertensive rats (SHR) and 20 control rats were used for measurements of Rb86 uptake of various organs. Hemodynamic measurements and the heart weight to body weight ratio showed a significant and sustained hypertension and increased heart rate in SHR; Ratio of Rb86 uptake in the kidney, brain, liver, adrenal gland, pancreas, and spleen to that in RV was smaller in SHR than that in the control rats. The ratio of Rb86 uptake of inner layer to outer layer of LV, which represents distribution of blood flow to the endocardial layer and epicardial layer, was not different between SHR and the control rats. The fraction of regional flow in the outer and inner cortex, juxtamedulla, and medulla of the kidney was not different between SHR and the control. The present preliminary study may suggest that myocardial blood flow in SHR is greater than that in the control rats. The relationship between cardiac hypertrophy and myocardial flow was discussed.