Study of correlation between elevation of blood pressure and tissue ACE activity during development of hypertension in 1K1C rats.

OBJECTIVES

This study sought to examine the alteration of local angiotensin converting enzyme (ACE) activity in the aortae, heart, kidney and lung as well as plasma during the development of hypertension in one-kidney, one-clip (1K1C) model, a non-renin-dependent model of renovascular hypertension.

METHODS

Experiments were carried out 2, 4, 8 and 12 weeks after induction of hypertension in male Sprague-Dawley rats. ACE activity was analyzed by high-performance liquid chromatography (HPLC) and the structural changes in aortae were investigated by measurement of cross-sectional area (CSA).

RESULTS

Our results show that ACE activity in aortae and heart was gradually increased with the development of hypertension and was more pronounced at higher blood pressure. In addition, there was a positive correlation between aortic CSA and elevation of blood pressure.

CONCLUSIONS

Our findings emphasize the significant role of local ACE, particularly in organs regulating hypertension (aortae and heart) in 1K1C model, in which circulatory renin is known to be unelevated.