A radioimmunoassay method for measuring plasma renin activity in rabbits showed a highly significant correlation (r=0.918) with the traditional biological assay method.
The radioimmunoassay for angiotensin I is a reliable and more efficient alternative to bioassay for measuring plasma renin activity and concentration in small volumes of rabbit plasma.
Effect estimate: r=0.918
p-value: p=<0.01
A radioimmunoassay method for ileu-5-angiotensin I was applied to the measurement of plasma renin in rabbits. In the present method, the volume of plasma sample, required for the determination of plasma renin activity and plasma renin concentration, could be reduced to 0.6 ml and 0.05 ml, respectively. A satisfactory correlation (r = 0.918) was found between the plasma renin activity measured by our bioassay method reported previously and that by the present radioimmunoassay method in each of 25 different plasma samples. A highly significant correlation (r = 0.968) was also observed between the plasma renin activity and the plasma renin concentration, both of which were measured by radioimmunoassays, as far as renin concentration remained under 200 ng/ml/hr. On the other hand, the present results appear to indicate that, when a high plasma renin activity was obtained, it was difficult to evaluate the actual plasma renin concentration. Therefore, it would be necessary to be cautious to apply the method for plasma renin activity on the renin rich plasma.
Kurihara et al. (1975) studied Plasma renin measurement in rabbits. Radioimmunoassay for Angiotensin I vs. Biological assay of plasma renin activity was evaluated on Correlation between plasma renin activity measured by bioassay and radioimmunoassay (r=0.918, p=<0.01). A radioimmunoassay method for measuring plasma renin activity in rabbits showed a highly significant correlation (r=0.918) with the traditional biological assay method.