Effect of intracerebroventricular injection of 6-hydroxydopamine on the peripheral catecholamine and angiotensin II in SHR.

This investigation revealed that the contents of A II and NE in plasma, heart and aorta and E content in plasma were significantly increased in SHR at the age of 12th week. At the same time the systolic blood pressure of SHR was much higher than that of the age-matched WKY. The intracerebroventricular administration of 6-OHDA in SHR at the age of 8th week not only prevented the development of hypertension, but also reduced the contents of NE and E in the brain regions, heart, aorta and plasma. Simultaneously A II content in heart, aorta and plasma was decreased. These results suggested that: 1. the renin-angiotensin system and peripheral sympatho-adrenal system are overactive in SHR, 2. the overactivity of peripheral sympatho-adrenal system is dependent on the central catecholaminergic neurons, and 3. the action of sympatho-adrenal system is partly responsible for the increase of A II content in plasma, heart and aorta in SHR.