Abstract
Inactive renin in the brain of spontaneously hypertensive rat was investigated. The results are as follows.
1) Treatment with either trypsin or glandular kallikrein of the brain tissue extract caused a rapid and apparent increase in the renin activity at either 0 or 27°C.
2) The molecular weight of the active renin was estimated to be 41,000 or 50,000 daltons, while that of the trypsin-activatable inactive renin was found to be 44,000 or 57,000 daltons on a column chromatography with Sephadex G-100.
3) The contents of the active renin was the highest in the hypothalamus, followed by the striatum, thalamus, midbrain, medulla oblongata, cerebral cortex and cerebellum, while the contents of the trypsin-activatable inactive renin was the highest in the hypothalamus, followed by the striatum, thalamus, cerebellum, midbrain, cerebral cortex and medulla oblongata.
4) These results suggest that inactive renin (s) exist in the brain of spontaneously hypertensive rat. It seems likely that the brain renin-angiotensin system is modulated by the conversion of inactive to active renin (s), which, in turn, plays at least in part a role in the blood pressure regulation through generation of angiotensin II in spontaneously hypertensive rats.
