Renin substrate release in response to perturbations of renin-angiotensin system

The role of the kidney in the regulation of plasma renin substrate and the release of this protein from rat liver slices were investigated. Physiological and pharmacological maneuvers were performed to perturb the renin-angiotensin system, including 24-h bilateral nephrectomy and furosemide administration to change renin and adrenalectomy and administration of dexamethasone to alter renin substrate. In the normal physiological range of plasma renin activity (PRA), no statistically significant linear relationship was evident between PRA and either plasma renin substrate or renin substrate released from liver slices. Stimulation of renin substrate by nephrectomy and dexamethasone administration were additive. Nephrectomy was also shown not to induce the release of a renin substrate-stimulating factor.