Study of Captopril Effect on Mesenteric Vascular Responsivness to Angiotensin I after Renovascular Hypertension Induction in Rat

Changes in tissues and general renin-angiotensin system’s function are the most important factors in cardiovascular disease such as essential hypertension. Recent research shows that general renin - angiotensin system affects the short and immediate response , and that of the tissues systems are effective in long period functions in controlling cardiovascular mechanism . This study was carried out to investigat the changes in function of tissue renin - angiotensin systems in mesenteric resistance vessels of Goldblatt tow kidney – one clip ( 2k - 1c ) renovascular hypertensive rats. Vascular response to angiotensin I and captopril effects were observed during a period of 2, 4 , 6 and 8 weeks post hypertension induction. The blood pressure of the hypertensive group was measured and compared with both sham and control groups. This study showed that after eight weeks of hypertension induction , captopril was unable to inhibit converting angiotensin I to angiotensin II . These changes were synchronous with precipitate process of increased arterial blood pressure in hypertensive animals. This was probably due to increased angiotensin converting enzyme activity or production of other enzymes , such as Chymase that , introduced a role in angiotensin II production . More investigation and accurate study of the process can probably affect to recognize the ethiology and efficient treatment of hypertension and other cardiovascular disease .