title: Plasma renin activity as a function of age in two new strains of spontaneously hypertensive and normotensive rats.
abstract: 1. Strains of spontaneously hypertensive and normotensive rats were selected by repeated inbreeding. 2. Brief ether anesthesia was shown to produce a two- to three-fold increase in plasma renin activity in both strains. 3. Plasma renin activity was significantly higher in young spontaneously hypertensive than in normotensive rats of the same age (5-7 weeks). After the ninth week plasma renin activity decreased and, at week 45, became significantly lower in hypertensive than in normotensive rats. 4. When hypertension was established a significant inverse relationship was found between plasma renin activity and systolic blood pressure in spontaneously hypertensive and in normotensive rats. 5. It seems unlikely that the renin-angiotensin system plays a major role in the maintenance of the established spontaneous hypertension in this strain. However, renin hypersecretion may be important in the early pre-hypertensive stage of genetic hypertension in rats.
mesh_terms: D000375:Aging; D000768:Anesthesia, General; D000804:Angiotensin II / Q000097:blood; D000818:Animals; D001835:Body Weight; D005019:Ethyl Ethers; D006973:Hypertension / Q000097:blood*; D008297:Male; D051381:Rats; D012083:Renin / Q000097:blood*
chemical_list: D005019:Ethyl Ethers; D000804:Angiotensin II; D012083:Renin