Renin and Antirenin in Treatment of Long Term Experimental Renal Hypertension in the Dog.

Summary and Conclusions 1. Courses of intramuscular injections of semipurified hog renin from cortex administered to dogs with experimental renal hypertensions of 4 or more years duration produced a significant reduction in blood pressure in those dogs which developed antirenin but not to normotension as previously found in dogs with chronic renal hypertension of 6 to 37 months duration. The 2 dogs which did not develop antirenin showed a maintained chronic pressor effect. 2. Passive immunization with homologous antirenin to hog renin produced a reduction in blood pressure to normotension or near normotension in dogs with experimental renal hypertensions of more than 7 years duration. 3. The mechanism of the decreased response to hog renin therapy in long term experimental renal hypertension in the dog is unknown. The results with passive immunization suggest that a lessened pathogenetic role for renin is not involved nor is progressive arteriolosclerosis. Possibly compensatory hypertensive mechanisms are more effective in the face of the gradually increasing antirenin titre of hog renin therapy than of the abruptly produced antirenin titre of passive immunization. 4. The results indicate that renin (or a closely related renal protein) is the principal pathogenetic factor even in experimental renal hypertension of many years duration in the dog.