Augmented intrarenal and urinary angiotensinogen in hypertension and chronic kidney disease
I n experimental hypertension due either to high salt in take or to renal manipulat ions, we repor ted previously tha t rats from a s train with a genetic predisposit ion to hyper tension produced a humoral factor which was t ransmit table in parabiosis and induced hypertension in rats genetically resistant to this condition. We surmised tha t the factor is identical in these two "k inds" of experimental hyper tension and have evidence tha t i t is produced by the kidneys of the hypertension-prone rats (1-4). The renin-angiotensin system is known to be coupled to sodium metabolism and is thought to be responsible for the development of renal hypertension. The mechanisms involved are by no means clear. We have therefore explored this sys tem in both strains of rats, and have s tudied its possible relat ion to the hypertensinogenic factor encountered in hypertension-prone rats. The most str iking single observation was tha t the kidney of the hypertension-prone rats produced a renin inhibitor tha t could not be demonst ra ted in animals from the hypertension-resis tant strain. The implications of these findings are discussed.